international codes and forms of codes for the transmission
TRANSCRIPT
Aye_. SECRETARIAT DE L'ORGANISATION METEOROLOGIQUE INTERNATIONAL£.
INTERNATIONAL CODES AND FORMS OF CODES
FOR THE TRANSMISSION OF WEATHER REPORTS.
1937.
OS'- 06 ~8 COMES INTO OPERATIO ON JANUARY, l st, 1937.
PRINTED BY EDWARD IJDO Ltd. - LEYDEN, 1937.
2
CONTENTS.
Pages.
Preface . ... ... .... .. . .. . . ........ .. . ... .. ...... . .. . .. . . .. .. . . . . . . . . . . .. . . . . . ...... 3
I. International codes and forms of codes ........ ... ....... ... ... . . ±-30
A. List of international forms of codes . . . . . . . . . . . . . . . . . . . . . . . . ±-7
B. The symbolic letters and their meanings . ............... . .
C. Specification of the codes ... . ... ....................... ....... . .
II. Hours of observation . . ... . .... ..... . ......... . .... . ................... .
III. Codes for ice messages ..... .. .................. ................ . . .... .
A . Code for reports of polar ice .. ............... . ....... .... .. ..
8-12
13-30
31
32--40
32-38
I. The symbolic letters and their meanings . . .. . . .. . . . . 33- 34
II. Detailed description of the ice-codes .. . . . . . . . . . .. . .. . . 34--------38
B . Regional code for ice messages . . . . . . . . . . . . . . . . . . . . . . . . . . .. . .. .. 39- .JO
ANNEXES.
I. Table of symbols for use on rharts.... . .... ........... ........ .. .. . .f2- .f3
II. Table for conversion of de~rees Fahrenheit and degrees Celsius . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
III. Table for converting barometric readings in millimeters into millibars . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
IV. Table for eonverting barometric readings in inches into milli hars . . . . . . . . . . . . . .. . . . . .. . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . .. . .. . . . . . . . . 46
PREFACE.
This pamphlet is a summary of Volume I of publication no. 9 of the Secretariat of the International l\IIeteorologicai Organisation and contains the full description of the international forms of code, the symbolic lett ers and their meanings completed with some additional code foTms and the codes for ice-messages.
Publication 11'0. 9 of this Secretariat - entitled ,,Les Messages synoptiques dn Temps" - cont ains information regar ding the meteorologi·cal messages of the whole world and regarding special codes (i. e. Japan). The publication is edited i·n: French and is to be obtained from this Secretariat (Utrechtsche weg 194 - De Bilt - Holland) .
Up to this moment the following volumes are published : Fascicule I Manuel des Codes internationaux. Fascicule II Liste des chiffres indicatifs des stations qui figurent
clans les mete-ogrammes synoptiques du temps emis par TSF.
Fascicule III Meteogrammes pour l 'Europe et la l\IIediterranec. Fascicule IV Les messages pour l 'aeronautique. Fascicule V - Meteogrammes pour l 'Afrique. Fascicule VI - l\IIeteogrammes pour l 'Amerique du Nord. Fascicule VII - Meteogrammcs pour l 'Asie et l 'Extreme-Orient. Fasciculc VIII - Meteogrammes pour l '.Ainstra lie, l 'Oceanie et la
N ouvelle-Zelande.
In preparation : .b'ascicule IX - Meteogrammes pour l 'Amerique du Sud.
De Bilt, Decembet 1936.
I. INTERNATIONAL CODES AND FORMS OF CODES.
A. LIST OF THE INTERNATIONAL FORMS OF CODES.
Reports from landstations.
W<wVhN 11 DDFV{N PPPTT UCHapp
2) IIICr,CM wwVhN11 DDFWN PPP TT UCnapp
3) IIICr,CM w·vvVh N11 DDFWN PPPT'l' UURRtw 4) IIICr,CM wwVhN11 DDFWN PP PTT UURRtw
Dr,CHDH/~ijj
Reports from ships at sea.
5) ,,Ship '' YQLLL lllGG DDF .. ww PPVTT 6) ,,Ship '' YQLLL lllGG DDF'ww PPVTT 9SKDKW CN J11ATc1 7) ,,Ship " YQLLL lllGG DDFww PPVT'l' 3Cr,Ci.rCnN Tc1KDKWN11 8) ,,Ship " YQLLL lllGG DDFww PPVT'r 6KDKCN Tc1dsAvVCn
Weather shipping messages.
9) DDFww PPVTT
Nephoscopic observations.
10) ,,Neph" III Gddvrvr
Reports of upper winds.
11) ,,Pilot" IIIGG . H 1ddv1 v1 .................. .... .. .. ...... .
12) ,,Pilot Ship" YQLLL lllGG H 1-ddv1v1 ........... .
Reports of upper air temperature.
13) ,,Temp" IIIGG (i ) P 1P 1P 1 TTTUU .. .... P 1P 1P 1 TTTUU (for the outstanding points of the curve (singularities ) ) (ii) 00000 TTTUU .. .. .. .. . 'l'TTUU (for fixed pressures) (iii) 00000 TTTPP TTTPP (for standard geodynamic heights) . (Preference shall be given to form i. )
14) ,,Temp ship " YQLLL lllGG (i) P 1P 1P 1 TTTUU ..... . P 1P 1P , TTTUU (for the outstand ing points of the cnrvc (s ingularities ) ) (ii) 00000 TTTUU .... .. 1.'TTUU (for fixed pressures) (iii) 00000 TTTPP ...... TTTPP (for standard geodynamic heights). (Preference shall be given to form i. )
dsvsapr
Aviation weather messages.
15 ) IIICLC~1 wwVhN11 DDFWN
Special groups. ')
16) IIIGG flt::.!.::. 'P'f"P . . CCC SVs FFF CN11h HHH hihhe · JJJ VVVDaVb LLL CCLdivd1 (hhhe) (CN11h ) PPP DaN3n3q QQQ DFxTTT1
WWW Djjjj yyy DaN4n 4 q zzz EEE'E'
Warnings to aircraft of dangerous phenomena and improvements of weather. ')
Dangel'ous pihenomena : 17) w 2GGgg l\'FlVIMMM IIICLCM wwVhN11 DDFWN
Improvement of ·weather: 18) w2GGgg BBBBB IIICLCM wwVhN1i DDFWN
19) ,,Previ'' VcVlt25
Short period forecasts for aviation.' )
YYGGO t1L1L1L~l R1R2lt26
Form of code for the transmission of monthly mean values of meteorological elements.
20) ,,Clirnat ' ' III PP TTT RiR1 (DDvv) (T1 T1T1) 21) ,,Occli'' QLlPP
Reports of Polar ice.
,, Ice'' YQLLL lllGG vs.ccJ uA0 d0D0 v0
,,Ice Nom. YGGI. VS.ccJ uA0 c10D0 v0
- - - --
5
' ) Th ese code forms a rc used exclu sively in ll'eather reports for a ir craft; see fo r desc ri ption the rrcnch edition of Pa1t I of publication no . 9 of the Secretariat.
6
NOTES.
Reports from landstations (code forms 1-4) . The second form of code is only used for the observations of 7 h
and 18 h. The meaning of the letters jjj varies according to time of observation and bet'lveen inland and coastal stations and ligihtships as foll ows :
at 0700 Gl\1:T at 1800 GMT
Inland stations T,,TnE T/ r ,E
Costal stations SVsE SVsE-
Light ships Tc1KDK T,J(DK
In tJhe messages relating· to mountain stations a special group may be given in the case wh en there are clouds whose base is below the level of th e station.
The group between brac·kets at the end of the code forms 3 and 4 is inserted for the benefit of stations in the tropics.
The code forms 1 nnd 2 are intended for use in temperate and high latitudes whel'C 1Jh e weather changes are of an irregular na1Jurc and are associa ted with the passage of d epressions, anticyclones, et c.
The code fo rms 3 and 4 arc intended for nsc in lower latitudes, where the weather has often pronounced cl iurna l variations, and bar.ometric changes are slight and regular .
Reports from ships at sea (code forms 5-8) . Code fot·m 7 is r ecommen·ded by the Director's Conference of
Copenhagen for selected ships, eit her SL'< or seven groups being used. For otlrnr shi·ps eit·h er form can be used and it is r ecommended
that at least 5 groups should be given in the message. In all cases the first 4 groups have exactly the sa me fonn.
Code form 6 is r ecommended for ships whi ch desir e to give also the state of the sea (S) .
Intercontinental collective messages (code fom1 9) .
'rhe messa•gcs mentioned above are collected itl' tihe collective issues for a whole continent or an analogue region.
The messages are lH·eceded by the Index numbers of the stations. In some countries the group containing the index numb ers is completed to a group of 5 figures, indicatin g special informations, i.e. :
Egy1)te : IIIA vV India : JICKW
'l'he ships messages incl'uded in the inter continental issues contain at least 4 groups (code form 5).
Weather shipping messages (code foDm 9). In the collective messages issued specially for t h e use of ships at
sea (weather shipping messages), the second and thii~cl groups of the r eport should be in the form
DD1" ww PPVTT
7
so that ships receiving the messages would get them in the same form of code as that of the universal groups of the ships' messages.
Transmission of monthly mean values of meteorological elements (code forms 20, 21).
'Dhe rmonthly mean values of meteorological elements for European regions will he transmitted at th.e end of the collective messages of 13 h observations.
The information of t he continent will be distributed as soon as possible and not later than the f ifth of the month. W hen tJhis date is a Sunday or a holiday the messages \rill be transmitted at the following day.
Compleirnentary information may be added for some particular stations : a)
b)
for some isolated stations, especially on islands, the transport of air masses (victor mean DDvv) for the determination of the gradient of th e mean pres&ure; for some representative stations (coastal stations, island stations or lig1ht ships) the t emperature of the watersnrface (T1T1T,) may be added.
Non meteorological information.
Non meteorological information and meteorological information other than that normally included in synoptic messages might be inserted in synoptic messages.') The repo1ts come at t he end of the messages.
Such reports arc normally prefixed by an indication of their nonmeteorological character.
The forms of collective messages as issued from a Wireless Transmitting Station, containing· reports from a whole country and from ships at sea (synoptic messages) .
Collective messages are normally arranged in sections, four of whiC'h comprise observations from landstations and one contains observations from ships at sea. Section I - preceded bij the word ,,SYNOP '' - contains the ordinary
observations from all stations. Section II - preceded by the word ,,SHIP'' - contains observations
from ships at sea. Section III - preceded by the word ,,NEPH;' - contains cloud obser
vations taken by a nephoscope. Section IV - preceded by the word ,,PILOT" - contains reports of
upper winds. Section V - preceded by the word ,,TEMP" - contains observations
of upper air temperature.
' ) See for· details r esolution :)ti of the Conference of Directors, \~arsaw , 1935.
8
B. THE SYMBOLIC LE'rTERS AND THEIR MEANINGS.
A Amount and characteristic of barometric tendency expressed by a single figure. See Code 01.
a Characteristic of barometric tendency during the period of three hours preceding the time of observation. (Res. 77j of Copenhagen and 45 of Warsa;w.) See Code 02.
C Form of predominating clouu according to scale of cloud forms when only one form is reported, as from ships at sea, or . for nephoscope reports . (Res. 77i of Copenhagen, Res. 8 and 38 of Wat·saw.) See Oode 1-0.
CL Form of low cloud. (Res. 77b of Copenhagen, Res. 37 of Warsaw.) See Oode 11. ·
CM Form of medium clo•ud. (Res. 77b of Copenhagen, Res. 38 of Warsaw.) See Code 12.
CH Form of cirrus cloud. (Res. 77b of Copenhagen.) See Code 13.
DD Direction *:') of the wind near the ground on . the scale 01-32 with the indication of unusual gustiness or a squall or line squall during the past hour or d irection from ·which a phenomeno n,- comes. (Res'. 71 of Copenha;gen. ) See Code 22.
D Direction;:' ) of the wind 6r ·direction f rom which a ph enomenon c'omes on the scale 0-8. 0 = stational'y. 1 = NE, etc. See Code 20.
Di-i/M Direction'':') of motion of hig'h cloud · when high cloud is r eported, and the ·direction of motion 6£ medi1Ullll cloud when there is medium cloud but no high . cloud reported on the scale 0-8. (Res: 54 of vVarsaw.) See Code 20. ·
DK Direction *:' ) from · whi ch swell comes on scale 0- 8, in which 1 =NE, 2 = E, ..... .'0 =no swell. (Res. 38 of London. ) See Code 20.
DL Direction ''') of motion of lo,¥ cloud on the scale 0-8 (Res. 54 of vV arsaw. ) See Code 20.
''') All d irnctio 11 s refer to t ru e N orth a11cl not to magnetic :.' fo rth.
9
dd Direction() ) of wind in t he upper air, or cloud movement, ori the scale 01-36, i. e. degrees from North divided by 10 and rounded off to tihe nearest whole number (00 = calm). 50 added if speed greater than 99 units. (See v1v 1 below.) (Res. 55 a11'd 59 of London. ) See Code 23.
ds Direction~:·) of movement of ship on scale 0-8, in which 1 = N ortheastwards, 2 = Eastwards, etc., ·O =no movement. (Res. 39 of London.) See Code 20.
E State of gTOlllld . (Res. 41 of v\Tarsruw. ) See Code 24.
F Force of wind on the Beaufort Scale. (Res. XXHb, etc. of Vienna.) See Code 30.
Forces above 9 a re reported as 9 jn all messages, with t he actual force in a wo1·d at the end, c. g. force 10 is reported at the end as ,,storm ten'', force 11 a s ,,storm eleven'', force 12 a s ,,storm twelve ' ' . Ships at sea, ho\\" evcr, repor t ,,gale ten", ,,storm eleven'', ,,hnnicane twelve' '.
1• x Maxi1J11um forc e of 1wind on the Beaufort Scale, with the fol-. low·ing· nwdification: {)=force 10, 1 =force 11, 2 =force 12, 3 =force 0-3, 4 = force 4, etc. (Res. 36 of \Va rsaw.) See Code 31.
G G ( gg ) Greenwich time (horurs and minutes ) of observation ( 01 = 0100, 12 = 1200, 13=1300, 24 =midnight).
H,
h
H eight at which upper wind is reported. See Code 44.
Hei1o·ht above the o·t·otrnd of the base of cloucl of form CL. (Re~. 55 of Lon:c101~, Res. 39 of Warsaw. ) See Code 43.
If, howe ver , th er e i s no cloud of for111 Cr. aucl there is cloud of form CM whose base is b elow 2300 · m, h . will r ef er to t his cloud.
If, h1owever, ther e are only fragment s of cloud of form Cr.
.b elow a more- ext ensive cloud whose base is below 2.500 m, then h nnd N h will rnfc r to this more extensive cloud and the fragments ll'ill b e r eported by a special addHional group. (Res. 39 of Warsaw. )
III Index numb er of the station .
jjj Mearning varies accordin g to time of observation and between inland and coastal stations and lightships, as follows :
At 0700 GM'l' At 1800 GMT
Inhwd stations 'l'u'l\,E TxTxE
Coastal Light ships sta t ions SVsE 'l'ctKDK sv.E Tc1KDK
•:•) All direction s r efo r tu t rue North and not to magnetic N orth.
10
K
LLL
111
N
'l'he state of the siwell in the open sea. (Res. 77 of Copen.hag·en.) See Code 51.
Latitude in degrees and tenths, the minutes being obtained by multiplying t1he third fi.gure by 6.
Longitude in degrees and tenths, the minutes being obtained as for latitude LLL.
Total cloud anwnnt. (Res. 77 a of Copenhao·en.) See Code 60.
Amount of cloud whose h eight is reported by h. (Res. 39 of vVarsa1.v.) See Code 60.
In ships r epor ts whcrn the heigh t of the cloud i s not given, N" indicates cmly the amount of low cloud (CrJ See for further details under h .
PP Pressure ·::') in whole milli'bars (Initial 10, 9, 8, etc. omitted) .
PPP Pressure'~) in millibars and tenths (Initial 10, 9, 8, etc. omitted).
P 1P 1P1 Pressure":' ) in whole millibars. li'igure 1 is to be omitted when pressure is above 1000 millibars. (Res. 46 of Warsaw.)
pp Amount of barometric tendency during the three hours preceding the t ime of observation ex1)ressed in fifths of millibars. (e.g. if bb = 27, the amount of bar.ornetric tendency in the last 3 hours is 5,4 rnb. ) (Res. 77j ·Of Copenhagen.)
Q Octant of the globe in which sihip is situated. (Res. 77 m of Copenha·gen.) See Code 70.
RR Amoruint of rainfall for the precedirng twelve hours; this report is issued twice a day. (Res. 77g of Copenhagen, R es. 55 of London.)
R1R1
s
See Code 74. 'rhe amoun t of ·rainfall is given for a period of 11, 12 or
13 hours, ending at t h e hour of t h e morning or evening observation.
In Europe a s the sy noptic evening observ.ation is made at 1800 GM'r, the amount of rninfoll given at 1800 GM'r, is the amount during the preceding 11 hours and at 0700 GMT the amount of rainfall dmi ng the preceding 13 hours.
Monthly amount of rainfall in centimetres. (Res. 6 of ·warsaw.) See Code 71.
State of sea. See Code 75.
*:') The values r efer to sea-level and include all corrnctions for index enor, temperature and gravity.
1'.'or mountain station s above 800 m the nllucs may refer to one of the heigths 1.000 geod. m., 2.000. geod. m., 3.000 geod. rn.
TT
TTT
11
Temperature of th e air in whole degrees Centigrade or Fahrenheit. For degrees Celsius under zero one adds 50 to the temperature . For degrees Fahrenheit under zero oll'e substracts the temperature from 100, i. e. a temperature minus T° Celsius is reported as 50 + T and a t emperature minus T° Fahrenheit is reported as 100 - T.
Tem.pera1Jture of 1Jhe air in degrees and tenths Centigrade (·5·00 added to n0gative values).
Minimum temperature in the interval of 12 hours t) ending at 0700 GlVI'l' (or at the hour 12 hours after the time of observing the maximum tempera ture. (Res. 55 of London.)
t ) In Europ e, thi s peTiod is 13 homs.
T s T s De1-v point temperature.
T,T, Maximum temperature in the interval of 12 hours ending at 1900 GlVIT t) (or the one of the hours 1 h , 7 h , 13 h or 19 h GlVIT following Jess than 4 hours after noon, loral t ime). (Res. 55 of London. )
u
uu v
t) In E urope, a s the synoptic eve ning observat ion i s made at 1800 GM'J', t h e period covers 011 1~' 11 hours.
Sea tem1)erature.
Tempera1Jnre of the surface of the sea on the same scale as the temperature of the air. (Res. 6 of \Varsavv.)
Difference between sea and air temp erature. (Res. 77d of Copenhaigen.) See Code 80.
Time of commencement of t he weather reported by \f\,T_ (Res. 54 of W arsa'W.) See Code 81.
Relative humidity of t he mr. (R es. 44 of \\Tarsaw.) See Code 84.
Relative humidity of th e air in %.
Hor~z·ontal visibility or the gteatest distance at which an obj ect can be recognised for what it is. (Res. 38 of London. ) See Code 85.
The tttblc mentioned on page 2i'i shall be co mpleted by the addition of a table g ivin g the distances at which lights of sp ecified candle po1Yer become invisible under the same condit ions of atmospheric transparency as those for which objects become invisible by day. 'l'hi s table is only provisionally . ( Res. 51 of Warsaw. )
v. Horizontal visibility towards the sea. (Res. 55 of London) . See Code 85.
12·
v1 v1 The speed of the wind in the upper air in kilometres per hour. (Res. 59 of London.) For values greater than 99 the last two figures o11!ly are used, and 50 is a·dded to t;he number indicating ·win1d direction dd. (Res. 36 of Copenhagen.) Values above 199 shall be indicated as 199 km. p. h. is indicated, the exact valllle shall be given in plain lall'!?:nage at the end of the ,.Pilot".
v .. v.. Relative speed of clouds as determined by nephosc·ope and expressed in radians per ho1ur. If ,,h' ', the heig,ht of cloud, is expressed in metres, the actual speed of cloud (v1 v1 ) is given in kilometres per hour by the equation (Res. 55 of London): See Code 35.
h
v s Average speed of ship during the period from which the barometric tendency is obtain·ed. (Res. 77k of Co·penhagen.) See Code 33.
'vV The weather in the interval preceding t1he time of the last synoptic observation. (Res. 77c of Cope11'hagen, Res. 42 of Warsaw.) See Code 9·0.
'l'his in ten ·al is Ii homs for obse r vat ion s at 0100, 0700, 1300 and 1900 GM'l' and 3 hours for ob se rvation s at 0400, 1000, 1600 a.ml 2200 'l'MG. In Europe the observatio11 is made at · 1800 hours; the n eriod at 1800 h is 5 h ours aud at 0100 h 7 hours.
For the intermediate ob servations and the xrnrniugs of dangerous phenomena a nd im prn,·e11H' n ts of weather t h e interval will be the period e lapsed since the tim e of the last observation transmitt ed . If the fi rst observation of the day is made at au h our other t h a n a s:vnoptic hou 1" the pr.rioc1 covered by 'i¥ will be one hour.
ww The actual weather at the time of observation with which is combined. whenever possible, the general c'haracter of the weather. See Code 92.
Y Day of the week: 1 =Sunday, 2 =Monday, 3 =Tuesday, 4= Wednesday, 5 = 'l'hursday, 6 _:_Friday, 7 =Saturday. Thr day refers to Gl\1T and not to local time, e. g., S1mday means the period from 0000 to 2400 on Sunday at Greenwich. (Res. 38 of London. ) See Oo·de 94.
YY Day of the month.
13 .
C. SPECIFICATION OF THE CODES . .
TABLE OF SYMBOLIC LETTERS.
(The symbolic letters are devided into decades.)
I 0 I 1 I 2 I 3 I 4 I 5 I 6 I
o~ I I A I a I I I I I io I c I cL I cM I c~ \ I I
I I
20 I D-Dttrn I DK-DL·ds I DD I dd I E I I I 30 I F I F, I I V s I I VrVr I I 40 I I I I h I HJ I I I 50 I I K I I I I I I
. I
60 I N-Nb I I I I I I I 70 I Q I R,Rl I
I
I RR I s I I I
80 I Td I tw I I I U I Vs-v \ I I
90 w WW y ,_I I I I I I I I
14 DE CA DE 0. (Codes 01 and 02. )
CODE 01. AMOUNT AND CHARACTERISTIC OF BAROMETRIC TENDENCY
EXPRESSED BY A SINGLE FIGURE (A).
Code figure Characteristics Change in last 3 hour~ in half-millibars
0 1 2 3 4
5 6 7 8
Barometer steady Rising slowly Rising Rising quickly Rising Yery rapidl.r
Falling slowly Falling Falling q•uickly Falling very rapidl~'
C ODE 02.
0 or 1 2 or 3 4 to 7 8 to 12 More than 12
2 or 3 4 to 7 8 to 12 More than 12
CHARACTERISTIC OF BAROMETRIC TENDENCY DURING THE PERIOD OF THREE HOURS PRECEDING THE TIME OF OBSERVATION (a) .
Code figure 0 ]
2 3 4
5 6
7 8 9
Rising then falling . Rising then steady, or rising then rising more slowly. I Unsteady. Steady or rising. Falling or steady, then r1s111g; rising- then r ising· mor e quickly.
or I Falling then steady; or falling then
Barometer now highce than or th e same as
3 hours ago.
Falling then nsuw:. )
falling more slowly. . Bar ometer now lower Unsteady. Falling. ) than 3 hours ago. Steady or r ising then fall ing : or falling then falling- mor e quickly.
Form of barogr am corresponding- with different code figures.
0 /'
I r~
2 ..r ~
3 /_
4 = _/ ./,)
5
6
7
8
9
\,,
~\......
\
' ""'\ "
In regions where th ere is a rnarkt'<l r egular diurnal \·ariation o:f: t he bal'Ometer , :f'igm·es 2 aud 7 may be nsed when the i·egular diurnal :variation is interrupted in such a way that the term ,,unstea dy '' gives the best description o:f: the character of the curve. (Res. 45 of -warsaw.)
DE fi ADE 1. (Codes 10- 13.)
CODE 10.
15
FORM OF PREDOMINA TING CLOUD ACCORDING TO THE SCALE OF CLOUD FORMS WHEN ONLY ONE FORM IS REPORTED, AS FROM
SHIPS AT SEA, OR FOR NEPHOSCOPE REPORTS (C).
Code figme 1 Cirrus
Cirrostratus Cirrocumulus Altocumulus Altostratns Stratoc'llmulus Nimbostratus
Ci Cs Cc Ac As Sc Ns
Code figure
0 1) 1 2 3 4 5 6 7 8 9
Code figure
0 1) 1 2
3
2 3 4 5 6 7 8 9 0
Cumulus or Fractocumulus Cumulonimbus Stratus or Fractostratus
CODE 11.
Cu or Fe Cb St or Fs
FORM OF LOW CLOUD (CL).
No low cloud. Fair weather Cumulus. Large Cumulus without anvi l. Cumulonimbus. Stra.tocumnlus formed by the spreading out of Cumulus. l.iayer of Stratus or Stratocumulus. Ragged low clouds of bad weather (Fractonimbus) . Fair weather Cumulus and Stratocumulus. Large Cumulus (or Cmnulonimbus) and Stratocumulus. Large Cumulus (or Cumulonimbus) and ragged low clouds of bad weather.
CODE 12. FORM OF MEDIUM CLOUD (CM).
No medium clouds. Typical Altostratus (thin) . Typical Altostratns (thick ) (sun or moon inYisible) or Nimbostratus. Single layer of Altoc·nmulns or high Stra.tocumulus.
' ) ·when the upper sky, mediulll ·sky or lo"· e 1· sky is invisible, either through darkness, through fog, duststorm or other surfa.ee phenomenon, or, in the case of the middle or upper sky, through the obstruction of a co mplet e lower layer of cloud, the cloud form shall b e indi cated b? a h?plH'n ( -) or a sol idus (bane de fraction ( /) . (Res. 72 of Copenhagen. )
4 Altocnmulus m isolated bands. I ndividually decreasing (often lenticular) .
5 Altocumulus in bands (increasing). 6 Altocumulus formed from the S'[)re:xding out of Cumu1'us. 7 Altocumulus associated with Altostratus or Altostratus with
parts· resembling Altocumulus. 8 Altocumulus Castellatus (or Altocumulus in ragged fragments). 9 Altocumulus in several layers generally associated with fibrous
veils and a chaotic appearance of the sky. N o t e: In the case of middle clouds Cirrocuniulus can appear
either alone or in combination with Altocumulw;;.
Code figure 0 1) 1 2
3 4 5
6
7 8 9
CODE 13. FORM OF CIRRUS CLOUD (CH).
No cirriform cloud. F ine Cirrus not increa·sing- : sparse. Fine Cirrus not increasing: abundant but not a continuous layer. Anvil Cirrus, usually dense. Fine Cirrus increasing: usually in tufts. Cirrus or Cirrostratus increasing: still below 45° altitude: often in polar ·bands. Cirrus or Cirrostratus increasing and reaching above 45° altitude : often jn polar bands. Veil of Cirrostratus covering whole sky. Cirrostratus not increasing and not covering vvhole sky. Cirrocumulus predominating, and a little cirrus.
Not e. Cirrocumulus may occ11r with any of the types 1 to 8.
DECADE 2. (Codes 20, 22, 23, 24.)
CODE 20. DIRECTION FROM WHICH THE WIND OR A PHENOMENON COMES (D) . DIRECTION OF MOTION OF IDGH CLOUD (Dnfai). ') DIRECTION FROM WHICH SWELL COMES (DK). DIRECTION OF MOTION OF LOW CLOUD (DL). DIRECTION OF MOVEMENT OF SHIP (d
5) .
Code figure 0 1 2 3 4 5 6 7 8
stationary NE E SE s SW w NW N
') See note page 15. ") If there are no cirrus clouds, the direction of medium clouds is given.
17 CODE 22.
DIRECTION OF THE WIND NEAR THE GROUND (DD) .
Code number With unusual With squall or
\Vind direction ·Calm NNE NE ENE
Code fi gure 00 02 04 06 08 10 12 14 16 18 2·0 22 24 26 28 30 32
gustiness a line squall 33 . 67 3,5 69 37 71 39 73
E ESE SE SSE s SSW SW Wff\N w WNvV NW NNW N
41 75 43 77 45 79 47 81 49 83 51 85 53 87 55 89 57 91 59 93 61 95 63 97 65 99
J o t e : The intermediate points of th e windrose are used wh en th e accuracy of observati011s makes it possible.
C ODE 23. DIRECTION OF WIND IN THE UPPER AIR OR CLOUD MOVEMENT (dd).
See description page 9.
Cod e figm e
0 1 2 3 4 5 6 7
8
9
Ground dry. Ground wet. GTo'lmd flooded.
CODE 24. STATE OF GROUND (E) .
Ground frozen hard and dry. Ground partly covered with snow or hail. Ground covered wit h ice or glaze d frost. Ground covered with thawing snow. Ground covered with snow less than 6 111. (15 cm) but ground not frozen. Ground covered with snow less than 6 in. (15 cm) and ground frozen. Ground covered with snow greater than 6 in. (15 cm) deep.
The figures 0- 3 give different cases of snowcover 0, the figure 4 gives snowcover 1-3 and the figures 5-9 give different cases of snowcover 4 where the snowcover, i. e. the proportion of ground covered with snow, is estimated on a scale 0-4.
18
DR CAD R 3. (Codes 30, 31, 33, 35.)
CODE 30.
FORCE OF WIND ON THE BEAUFORT SCALE (F).
'l'elegraphic Limites of speed number · Beaufort number km per h. m/scc.
0 0 0- 1 0- 0.5 1 1 2- 6 0.6 - 1.7 2 2 7- 12 1.8 - 3.3 3 3 13 18 3.4 - 5.2 4 4 19 26 5.3 7.4 5 5 27 35 7.5 9.8 6 6 36 44 9.9 12.4 7 7 45 5± 12.5 15.2 8 8 55 65 15.3 18.2 9 9 66 77 18.3 21.5 9 10 78 - 90 21.6 25.1 9 11 91 -104 25.2 - 29 9 12 > 104 > 29
The speeds refer to a h eight of 30 feet (6 m) above ground in an open situation.
Forces above 9 arc reported as 9 in all messages, with the actual force in a word at the encl, e. g. force 10 is reported at the end as ,,storm ten", force 11 as ,,storm eleven", force 12 as ,,storm twelve".
Ships at sea, however, report ,,gale ten " , ,,storm eleven " , ,,hurricane twelve''.
CODE 31.
MAXIMUM FORCE OF WIND (F) ON THE BEAUFORT SCALE
WITH 'l'HE FOLLOWING MODIFICATION :
Code figure Beaufort numbers
0 force 10 1 11 2
" 12
3 0 a 3 4 4 5 5 6 6 7 7 8 "
8 9 9
Code figure 0 1 2 3 4 5 6 7 8 9
C ODE 33.
SPEED OF SHIP IN KNOTS (v 5).
Speed in nautical miles per hour
CODE 35.
0 1 - 3 4 - 6 7 - 9
10 - 12 13 - 15 16- 18 19-21 22-24 > 24
R ELATIVE SPEED OF CL OUDS (v,.v).
See descr iption on page 12.
DECADE 4. (Codes 43, 44.)
C ODE 43. HEIGHT OF BASE OF CLOUD OF FORM CL (h).
Code figure H eigh t 0 0 to 50 m 1 50 to 100 m 2 100 to 200 m 3 200 to 300 m 4 300 to 600 Ill
5 600 to 1000 Ill
6 1000 to 1500 m 7 1500 to 2000 m 8 2000 to 2500 m 9 no low cloud
19
If, however , ther e is no cloud of form CL and there is cloud of form C111 whose base is below 2500 m, h -will refer to this cloud. (Res. 39 of vV arsa:w.)
If, however, there ar e only fragments of cloud of form CL below a more ext ensive cloud whose base is below 2500 m, then h and N h will refer to this more extensive clou d and the fragments will be reported by a special addit ional group . (Res. 39 of W arsa:w.)
20
CODE 44. HEIGHTS A T W HICH UPPER WIND I S REPORTED (H,) .
Code figure
1 2 3 4 5 6 7 8 9
Metres above sea-level 200 5'00
1000 1500 2000 3000 4000 5000 6000
vYhen the heights are above 6000 m the following code is used: Code figure
0 1 2 3 4 5 6 7 8 9
Metres above sea-level 7000 8000 9000
10000 11000 12000 13000 14000 15000 16000
When the synoptic r eports do not include the observation of wind at the surface at stations whose pilot-balloon results are transmitted, the groups of figures giving the upper wind at each of these stations are preceded by an additional group H, ddv,v, giving the wind at the surface in the same code as the observations of upper wind, viz. dir ection on seale 01-36 and velocity in kil<ometres per hour. Th e figure 0 ('zero) is used as the first figure of this additio·nal group.
Code figure
DECADE 5. (Code 51.)
CODE 51. STATE OF SWELL IN OPEN SEA (K ) .
0 None.
1 Short or average length } Low. 2 Long 3 Short 4 Average length Moderate height. 5 Long 6 Short
~ 7 Average length Heavy. 8 Long
9 Confused.
D ]!} CA DE 6. (Code 60. )
CODE 60. CLOUD AMOUNT (N ).
AMOUNT OF CLOUD WHOSE H E IGHT I S REPORTED BY h (Nh).
Code figure Cloud Amount (in tenth s)
0 Tra ce.
1 2-3
4, 5, 6 7-8
9 More than 9 but with openings.
10
21
0 1 2 3 4 5 6 7 8 9 Sky obscured by fog , dust storm or
other phenomenon.
NO TES. I. Code fig'ure 0 is to be used only wh en the sk y is complet ely fr ee
from cloud. Code figure 8 is to be used only when the sky is completely covered with cloud so that no blue sky is visible.
II. If the sun or stars c31n be seen through fog or mist and th ere is no evidence of cloud above the fog or mist, the amount of doud N should be taken as zero. If cloud can be seen th rou g'h the fog or mist the amount of cloud should be estimated as well as possible m1d the form or forms noted to th e best of the observer's ability. The cloud fo rms and cloud amount should th en be reported in the ordinary way as if fog or mist were not present.
III. :B'or mountain stations N1i is obtained by counting the places ·where mountains come through the clouds as if they were covered with clouds.
IV . In ships reports where the height of the cloud is not given N1i indicates only the amount of low cloud ( Cd.
DECADE 7. (Codes 70, 71, 74, 75. )
CODE 70. OCT AN T OF TH E GLOBE IN WHICH SH I P I S SITUATED (Q ).
Code figure Longitude from H emispher e Greenwich
0 0- 90 w
~ 1 90--180 w 2 180 - 90 E 3 90- 00 E
Northern.
5 0- 90 vV ( 6 90- 180 \!.,T 7 180 - 90 E ~ 8 90- 00 E
Southern . .
22
CODE 71.
MONTHLY AMOUNT OF RAINFALL IN CENTIMETRES (R1R 1).
For amounts above 8 mm and less than 91 cm the value is given in whole centimetres. For amounts of 8 mm or less and above 90 cm the following code numbers are used:
Code figure Signification 91 1 mm 92 2 mm 93 3 mm 94 4 mm 95 5 mm 96 6 mm 97 7 mm 98 8 mm 99 more than 90 cm
When figure 99 is reported in the code group the actual precipitation m cm is added in a separate group of 2 or 3 figures. ·
CODE 74.
AMOUNT OF RAINFALL FOR THE PRECEDING 12 HOURS (RR).
The amount of r ainfall is expressed in whole millimetres with the following exceptions :
Code figure 91 92 93 94 95 96 97 98 99
Specification of certain meanings.
Meaning 0.1 mm. 0.2 mm. 0.3 mm. 0.4 mm. 0.5 mm. 0.6 mm. Some rain but not measura·bie. More than 90 mm. Measurement impossible or unreliable.
The amount of rainfall is given for a period of 11, 12 or 13 hours, ending at the hour of the morning or evening observation.
In Europe, as t he synoptic evening observation is made at 1800 GMT the amount of rainfall given at 1800 GMT is the amount during the preceding 11 hours and at 0700 mwr the amount of rainfall during the preceding 13 hours.
Code figure
0 1 2 3 4 5 6 7 8 9
Code figure 0 1 2 3 4
5 6 7 8 9
Calm. Smooth. Slight. Moderate. Roug·h. Very rough. High. Very high . Precipitous. Confused.
Com!: 73. STATE OF SEA (S) .
DECADE 8. (Codes 80, 81, 84, 85.)
CODE 80. DIFFERENCE BETWEEN SEA AND AIR TEMPERATURE (Tct).
> 5.0° C. 3.1-5.0 1.6-3.0 0.6 - 1.5 0.0 - .0.5 0.1-0.5 0.6 -1.5 1.6-3.0 3.1-5.0
> 5.0
; ~
!
Air temperature same as or hig·her than sea temperature.
Air temperature lower than sea temperature.
CODE 81.
23
TIME OF COMMENCEMENT OF THE WEATHER REPORTED BY W (tw) .
Code figuTc
0 1 2 3 -± 5 6 7 8 9
- or I
nothing to report.
0 - 1 h ) 1 - 2 h 2 - 3 h 3 - 4 h g = ~ j~
1
. before the time of observation.
6 - 7 h 8 - 10 h above 10 h no observation.
24
CODE 84.
Code f ig ure
1
RELATIVE HUMIDITY (U) .
% 0 - 19
20 - 29 30 - 39 40 - :1:9 50 - 59 60 -- 69 70 - 79 80 - 89 90 - 94 95 - 100
2 3 :I: 5 6 7 8 9 0
If a Service desires to distinguish separately humidity of 0- 9 % this should be done by reporting 0- 9 by a solidus (/) or a hyphen (-) .
CODE 85. HORIZONTAL VISIBILITY OR THE GREATEST DISTANCE AT WHICH AN
OBJECT CAN BE RECOGNISED FOR WHAT IT IS (V-V.).
See table page 25 . NO TES.
Obscuring matter in the atmosphere such as mist or fog limits the distance to which objects can be seen. The horizontal visibility V is the greatest distance at which an object can be recognised for what it is. The obj ects for observations of visibility must be large enough for the observer to be able to recognise them readily in a perfectly clear atmosphere.
At night or when the light is poor, observations of visibility are made with the assistance of lights.
In order to ensure comparable observations at night, specifications are included in the table mentioned on page 25, r egarding the distances and candle powers of lights for use with night observations. This section of the table is to be regarded as provisional.
HORIZONTAL VISIBILITY FROM SHIPS AT SEA (V5).
Visibility towards the sea for coastal stations (V) or visibility for ships on sea CV. ) . Nearly the same scale is used. Code
figure 0 1 2 3 4 5 6 7 8 9
Dense fog, obj ects not visible at 50 yards. Thick fog, ob j ects not visible at 1 cable. Fog, ob j ects not visibl e at 2 cables. Moderate fog , objects not visible at 112 mile (na•utical). Thin fog· or mist, obj ects not visible at 1 mile (naut ical ), Visibility poor, obj ects not visible at 2 miles (nautical ). Visibility moderate, obj ects not visible at 5 miles (nautical). Visibility good, objects not visible at 1'0 miles (nautical) . Visibility very good, obj ects not visible at 30 miles (nautica 1) . Visibility excellent, obj ects visible i;i,t more than 30 miles (nautical ).
Code Figure
v 0
1
2
3
4
5
6
7
8
9
Daylight Observations. Column K.
I Objects not visible at 50 .m (or
% cable). I Objects visible at 50 m but not
at 200 m (1 cable). Objects visible at 200 m but not
at 500 m (or 2 cables). Objects visible at 500 m but not
at 1000 m (or 4 cables). Objects visible at 1000 m but not
at 2000 m (or 1 nautic. mile). Objects visible at 2000 m but not
at 4000 m (or 2 nautic. m). l Objects visible at 4000 m but not
at 10 km (or 5 nautic. m). Objects visible at 10 km but not
at 20 km (or 10 nautic. m). I Objects visible at 20 km but not
at 50 km (or 30 nautic. m). I Objects visible at 50 km or more.
Table for Visibility.
Ni g h t 0 b s er vat ions (Provisional) .
If lights at the same distances as objects
are to be used they must be of the
cp. shown below.
0.13 cp. at 50 m
0.9 cp. " 200 m I
3.5 cp. ,, 500 m
10 cp . ,, 1000 m
35 cp. ,, 2000 m
JOO cp. ,, 4000 m
420 cp. " 10 km
20 kml 1250 cp. "
4500 cp. " 50 kmj
from 20000 cp. " 150 km
If lights of fixed intensity of 100 cp . are used they must be
at the following distances:
Object distance
50 m
200 "
500 "
1000 "
2000 "
4000 "
lOkm
20 "
I
Distance for 100 cp. light
100 m
330 "
740 "
1340 "
2300 "
4000 "
71/z km
12 "
At greater distances a 100 cp . is not suitable.
The candle~powers and distances specified for night observations are to be regarded as provisional. tV c.n
26
DE CA DE 9. (Codes 90, 92, 94. )
CODE 90. WEATHER IN THE INTERVAL PRECEDING THE TIME OF
THE LAST SYNOPTIC OBSERVATION (W).
This interval is 6 hours for observations at 0100, 0700, 1300 and 1900 TlVI G; 3 hours for observations of 0±00, 1000, 1600 and 2200 GMT.
In Europe the observation is made at 1800 ; the period at 1800 h is 5 hours and at 0100 h 7 hours.
For the intermediate observations and the warnings of dangerous phenomena and improvements of weather the interval will be the period elapsed since the time of the last observation transmitted. If the first observation of the day is made at an hour other than a synoptic hour, the period covered by vV will be one hour.
Code figure
0 1 2 3 4
Fair (clear or slightly clouded). Variable sky. Mainly overcast. Sandstorm or duststorm or storm of drifting snow. 1 )
Fog or thick dust haze (visibility less than 1000 metr es, 1100 yards).
5 6 7 8 9
Drizzle. Rain. Snow or sleet. Showers. 2
)
Thunderstorm. 2)
CODE 92. WEATHER AT TIME OF OBSERVATION AND GENERAL CHARACTER
OF THE WEATHER (ww).
Code figure 00-49 No p·recipitation cbt time of obser ucition. 00-19 Abbreviated description of sky and special · phenomena. 00 Cloudless. 01 Partly cloudy. 02 Cloudy. 03 Overcas t. 04 Low fog, whether on land or at sea. 05 Haze (but visibility great er than 2000 m., 11/t_ miles). 06 Dust devils seen. 07 Distant ligihtnh1g. 08 Mist (visibility between 1000 and 2000 111. , 1100 yards ancl
Jl!t miles) .
') In the case of a sandsto rm at temperature below 0° C the word ,,sandstorm '' should be added in clear.
') If wi th h ail, the word ,,hail" may be reported at t h e end of th e message.
09 JO 11 12 13 14 15 J6 17 18 19
20-29 w 21 22 23 24 25 26 27 28 29
Fog at a distance but not at the station (or ship). Precipitation within sigh t. Thunder, without precipitation at the station. Dust storm visible but not at the station. Ugly, threatening sky. Squally weather. Heavy squalls "\\T aterspouts seen m last 3 hours.
Precipitation in last hour but not at time of observation. Precipitation (rain, drizzle, h ail, snow or sleet) .
Rain
27
Drizzle l Snow other than showers. Sleet _ In last llO'ur but
Rain sho wer (s) . Snovv shower (s). H ail or rain and hail shower (s) . Slight thunderstorm. H eavy thunderstorm.
j not at time of observation .
30-39 Dust storms and storms of drifting snow.
3·0 31 32 33 34 35 36 37 38 39
(Visibility l ess t han 1 .000 m., 1.100 yards.) Dust or sand storm.
" has decreased.
" " no appreciable change. has in cr eased.
Li~~e of dl{~t st o1'.~1s. Storm of drifting snow. Slight storm of drifting H eavy ,, Slight Heavy "
snow
" } generally
} generally
low.
high.
40-49 Fog or thick dust haze.
40 41 42 43 44 45 46 47 48 49
(Visibility less than 1'000 m, HOO yards.) Fog. Moderate fog in last hom l Thick fog in last hour f F'o g, sky discernible l
sky not discernible \ sky discernible l sky not discernible \ sky discernible I
,, sky not discernible \ Fog in patches.
but not at time of observation.
h as become thinner during last hour.
no appreciable chan ge during last hour.
has begun or become thicker during the last hour.
28
50-99 Precipifotion cit time of observcition. 50-59 Drizzle (precipitation consisting of numel'ous minute drops). 50 51 52 53 54 55 56 57 58 59
Driz·zle. Intermittent Continuous Intel'!11ittent Continuous Intermittent Continuous Drizzle and fog. Slight or moderate Thick
60-69 Rain. 60 61 62 63 64 65 66 67 68 69
Rain. Intermittent Continuous Intermittent Continuous Intermittent Continuous Rain and fog. Slight or moderate Heavy
70-79 Snow. 70 Snow -0r sleet. 71 Intermittent 72 Continuous
slight drizzle.
moderate drizzle.
thick drizzle.
drizzle and rain.
slight rain.
moderate rain.
heavy rain.
rain and snow .
slight snow in flakes. 73 Intermitt ent 74 Continuous moderate snow in flakes. 75 Intermittent 76 Continuou!" heavy snow in flakes. 77 Snow and fog. 78 Granular snow (frozen drizzle). 79 Ice crystals.
80-89 Shower (s ).
80 Shower (s). 81 Shower (s) of slig'ht or moderate i 82 ,, heavy rain. 83 s'1io·ht or moderate ~
" !::> snow. 84 "
,, heavy 85
" ,, slight or moderate i rain and 86 ,, heavy snow. 87 ,, ,, granular snow. 88 ,, ,, slight or moderate ~ hail, or rain 89 ,, heavy and hail.
29
90-99 Thunderstorm. 90 'l'hunderstorm. 91 Rain at time l thunderstorm during last hour, but not 92 Snow or sleet at time I at time of observation. 93 Thunderstorm, slight without hail or
:;oft hail, but with rain (or snow) 94 Thunderstorm slig-ht with soft hail 95 Thunderstorm moderate wi1'110ut hail ,
hnt with rain (or snow) 96 Thunderstorm moderate with soft hail at time of observation 97 'rhunderstorm heavy without hail, but
with rain (or snorw) 98 Thunderstorm combined with ·dust
storm 99 Thunderstorm heavy with hail
NOTES.
J. ·whenever the description intermittent is used the fog or precipitatiou has not continued without break during the last hour.
2. In general, the largest number of the code which applies to the ·weather at the station will be used.
3. Th0 state of the sky is normally reported in the cloud code, and not in this code for present weather.
4. ·when the sky is discernible through the fog the cloud is report ed as if no fog were present. But when the sky is not discernibl e. the cloud amount is r eckoned as 1'0 and the height of base of low cloud as zero.
5. l<,igures 20~29 will never be used when there is precipitation actually falling at the time of observation.
6. Figures 80-89 will only be used when the precipitation is of the shower type, and when precipitation is actually falling at the time of observation. The clouds which give showers are isolated clouds, and the showers are therefore always of short duration. Between the showers there is a definite clearance unless stratiform clouds are filli>ng the interstices between the shower clouds. Figures 83 and 84 r efer to the phenomena commonly known in N. America as ,,snow flurries".
7. It is desirable that Central Institutes or the Directors of Services should give explicit instructions to their observers to use wherever possible the numbers other thcin 3·0, 40, 50, 60, 70, HO, 90. The seven numbers have been introduced to meet certain exceptional cases and it is desirable that their use should be co11fined as far as possible to those exceptional cases.
30
Code number 1 2 3 4 5 6 7
CODE 94.
DAY OF THE WEEK (Y) .
D ay
Sunday. Monday. Tuesday. Vv ednesday. Thursday. Friday. Saturday.
The day refers to GlVIT and not to local time.
31
II. HOURS OF OBSERVATION.
Hours at which the synoptic messages ought to be taken are the following:
a. Observations of landstations.
If possible the observations are made at the standard hours:
GM'l' 01 h, 07 h , 13 h, 19 h. (Res. XVIIfo of Vienna.)
In Western and Central Europe, Scandinavia and North Africa the observations are made at the following hours:
GMT 01 h, 07 h, 13 h, 18 h. (Res. XVIIIc of Vienna.)
The observations at the stations of SE-Europe and the Near East (Syria, Egypt, Iraq, Turkey in Asia) are made at:
GMT 06 h , 12 h , 18 h. (Res. 66 of Copenhagen.)
In the parts of the continents where it is impossible to use the standard hours for the synoptic observations, the observations are made at hours which not vary by more than l hour on either side of the standard hours, i. e. any hour selected should be included in the periods 0 h-2 h , 6 h-8 h, 12 h-14h, 18 h-20 h GMT.
The observations of 13 h GMT are of special importance. (Res. XVIIIe of Vienna.)
b. Observations from ships at sea.
On board of ships at sea equipp ed with meteorological instruments (selected ships, see r es. 24 of Copenhagen) the observations are made at the following hours:
GMT 00 h , 06 h , 12 h , 18 h. (Res. 25 of Copenhagen.) AH ships which cooperate in the radiometeorological service of
the Oceans are invited to make the observations at the standard hours. The observations of 00 h and 12 h are of special importance. (Res. 26 of Copenhagen.)
NOTE.
The observations at the fixed hour should begin not more than 10 minutes before the exact hnur and should be completed at the exact hour. The observation of the element of whic.h the variation was most rapid, should, as far as possible, be made last.
32
III. CODES FOR ICE MESSAGES.
A. CODE FOR REPORTS OF POLAR ICE.
The following code is adopted for international use : 1) Code for ships:
,,I CE'' YQLLL lllGG vs.ccJ nA. cl .D. v c ·
2) Code for land stations: ,,ICE" Norn YCiGI. VS.ccJ uA0 d0 D.v0 •
This code is prepared on the basis of the Ice-terminology in the Atlas of Sea Ice by A. Maursta,d. 1
) The ice r eports give information which is a) of importance to navigation and b) form a basis for a study of problems relative to ice in the sea. The ice r eports should, therefore, be as complet e as possible and contain a detailed description of the ice conditions, including the changes at the moment of observation.
The ice l'eports shall be treated so fal' as collective issues are concerned in the manner r ecommended for non-meteorological information.
These messages give information which is very important for navigation and form a basis for a study of the ice conditions.
The code begins with the word ,,Ice'' in order to indicate that the message concerns ice. i ext follow two ,groups referring to position and time. 'Dhe first group contains the day of the week at which the observation is ma,de, the octant of the globe where the ship is and the latitude. The second group delates to t he longitude and the t ime of observation in GMT. The land stations give after the name of th e statiorn a group relating to the day of the week, the time of obser vation and the sector to which the observation belongs.
'Dhe ice r eport itself is condensed in two 'groups of five letters.
First group. The first group begins with the visibility which always must be
reported since otherwise the meaning of the following information becomes unclear. It is fo llo'wed by information as to the extension of the ice covered area and by a description of the ice, by means of two figures w'hich have been arranged in deca,des and is closed with information as to the possibility of navigation. These decades r efer to: 00 - Direction to the ice-blink or ice-edge. W - State of newly frozen ice. 20 - State of the winter drift-ice without leads near shore. 30 - Situation of shoreleads with r egard to the fast ice. 40 - State and character of the hummocked winter-ice \\·ith r egard
to the shore-leads.
' ) Publi sh ed by Det Nors kc Videnska.ps·Akaclcmi , Oslo, Norway .
33
50 Condition of the polar-ice. 60 Position of polar-ice and shore-leads. 70 Calved ice and ice-bergs. 80 - The fast ice.
Attention is drawn to the combinations 30, 40 and 60. These combinations have been ins·erted in vievv of the fact that from a ship lying in t'he ice it may be possible to see a shore-lead, but the width of the lead ca1rnot be estimated.
No definite information is send if the distance to ice or lead is greater than 5 nautical miles. The reason is that from a ship the ice conditions cannot be judged at greater distance, and the same applie:,; to land stations, unless they are situated at great altitude. For such statio11•s it may become desirable to make use of the spare decade.
"\Vhen several types of ice are present, what ·often ha·ppens, the type shall be reported, which according to its character and occurrence forms the greatest obstacle to navigation.
Second group. The second group contains information as to:
a) the average thickness of the ice, b) changes in the ice, c) direction to open~ water or ··water-sky, d) ice-drift, e) speed of ice-drift.
When it is impossible to give this information the group is left out or the missing elements are replaced by x.
I. THE SYMBOLIC LETTERS AND THEIR MEANINGS.
A. Changes of the ice. See code ,,Ice •00". cc Character of the ice. See code ,,Ice 01 ". D. Direction':'' ) of the ice-drift ·On the scale 0-8. 0 =no drift.
GG I . J LLL lll Q s. u
See c·od·e ,,Ice 02". Direction to the open water on the scale 0-8. 0 =no open water or water-sky. See code ,,Ice 03 ". Greenwich time of observation. Sector to which ice report refers.
. Possibility of navigation for steam or motor ships. See code ,,Ice 04" .
Latitude in degrees and t enths of a degree l according to the InLongitude in degrees and tenths of a degree terna~ional :M:eteoOctant of the globe where the ship is rolog1cal Code 1935.
Extent of the part of the sea which is cover ed by ice (in tenths). See code ,,Ice 05". Thickness of the ice. See code ,,Ice 06 ". Speed of ice-drift. See code ,,Ice 07 ".
,;:') All directions refer to true North and not to magnetic North.
34
V Horizontal visibility according to the International Meteorological Code 193·5.
Y The day of the week.
II. DETAILED DESCRIPTION OF THE ICE-CODES.
,,Ice".
I 0 1 2 3 4 5 I 6 I
7 8 9
00 I Ae cc De de J S" I u I Ve
CODE ,,ICE 00".
CHANGES OF THE ICE (Ae).
Code figure 0 No perceptible changes. 1 Ice melting. 2 Ice melting and opening. 3 I ce opening. ± Ice opening rapidly . 6 Young ice freezing. 7 Ice closing. 8 I ce closing rapidly. 9 Ice pressing together and hummocking.
CODE ,,ICE 01 ' '.
CHARACTER OF THE ICE (cc).
(The figures are references to the Atlas of Sea Ice by A. lVIaurstad.)
Code figmc 00-09 No ice or ice at distance (ice-blink or ice-edge). 00 No ice. 01 Ice blink or ice-edge rn NE. 02 ,, ,, ,, ,, ,, E. 03 ,, ,, ,, ,, ,, SE. 04 ,, " " ,, ,, s. U5 ,, ,, ,, ,, ,, ff\V. 06 ,, ,, ,, ,, ,, vV. 07 " " " " ,, N\~T . 08 ,, ,, ,, ,, ,, N. 09 Observation impossible owing tl) poor visibility.
10-19 Newly frozen ice. 10 Newly frozen ice, specification not possible. 11 Ice film ( 0-2 cm). 12 Slush. (Fig. 1.) 13 Snowslush. 14 Ice-rind (2-5 cm). (Fig. 2.) 15 Pancake-ice. (Figs. 3-4.) 16 Sludge. (Fig. 5.) 17 Sludge-ice. (Fig. 7.) 18 Slob-ice. 18 Slob-ice. 19 Young ice (5-20 cm). (Figs. 8-9 .)
20-29 20 21 22 23 2-± 25 26 27 28 29
30-39 30
~~ l 33) 34 \ 35 ( 36 \ 37 \ 38 1 39 \
Winter drift-ice without leads near shore. \¥inter drift- ice, specification not possible. Brash-ice. (Figs. 6 and 17.) Cake-ice. Growlers and/ or Growler ice. (Figs. 15 and 16.) Level-ice. (Figs. 10, 11 and 12.) F loes of winter-ice. (Fig. 31.) Ordinary winter-ice. (Fig. 30.) Hummocked winter-ice. (Figs. 13, 14 and 28.) \¥inter-ice with ice-bergs outside.
" " " " between.
Winter-ice, no specification, with leads near shore. vVinter-ice, no specification, with lead near shore, further fications not possible. vVinter-ice, no specification, l outside of shore-lead, width of lead: Shore-ice strip of 'vinter-ice, uo specification, open water outside, width of strip : J_,ead in winter-ice, no specification, parallel to shore, distance from shore:
I \ I \
less than 1 n . mile. 1-5 n . miles. more than 5 n. miles. less than 1 n. mile. 1-5 n. miles. more than 5 n. miles. less than 1 n. mile. 1-5 n. miles. more than 5 n. miles.
Hummocked winter-ice with leads near shore.
35
speci-
40-49 40 Hummocked winter-ice with lead near shore, further specifications
41 I 42 ( 43)
44 / 45 ( 46 )
47 / 48 ( 49)
not possible. Hummocked winter-ice out- \ side of shore lead, width of ( lead: · J
Shore-ice strip of hummocked winter-ice, open water outside, width of strip: Lead in hummocked wiuterice, parallel to shore, distance from shore :
I \ I \
less than 1 n. mile. 1-5 n . miles. more than 5 n. miles. less than 1 n . mile. 1-5 n. miles. more than 5 n. miles. less than 1 n. mile. 1-5 n. miles. more than 5 n. miles.
36
50-59 50 51 52 53 54 55 56 57 58 59
60-69 60
ol ! 62 68
64 ! 65 66
67 ! 68 69
70-79 70 71 72 73 74 75 76 77 78
79
Polar-ice without leads near shore. Polar-ice specification not possible. Cakes. (Fig. 27. ) Growler-ice. (Figs. 19, 25 and 40.) Growler-ice. (Fig. 18.) Floes. (Figs. 20, 26 and 29.) Ordinary polar-ice. Hummocked polar-ice. (Figs. 21, 22 and 24.) Compact fields of polar -ice. (Fig. 23.) Polar-ice with ice-bergs outside. Polar-ice with ice-bergs between.
Polar-ice with leads near shore. Polar-ice with lead near shor e, specification not possible. Polar-ice outside of shore, ( less than 1 n . mile. width of lead: 1-5 n . miles.
more than 5 n. miles. Shore-ice strip of polar-ice, open wa ter outside, width of strip: Lead in polar-ice, parallel to shore, distance from shore:
Calved ice and ice-bergs.
( ~ )
less than 1 n . mile. 1-5 n. miles. more than 5 n. miles. less than 1 n . mile. 1- 5 n. miles. more than 5 n. miles.
Calved ice or ice-bergs, specification not possible. Calved ice only. Bergy bits. (Figs. 39 and 40. ) Small tabular ice-bergs, length less than 50 metres. (Fig. 32.) Small irregular ice-bergs, height less than 5 metres. (Fig. 35.) Medium tabular ice-bergs, length 50- 200 metres. (Fig. 33. ) Medium irregular ice-bergs, height 5-20 metres. (Fig. 34. ) Great tabular ice-bergs, length 200- 1000 metres. (Fig. 38.) Great irregula r ice-bergs, height greater than 20 metres. (Figs. 36 and 37.) Ver y great tabular ice-bergs, length greater than 1 km.
80-89 The fast ice. 80 Level fast ice, no further specif ication p ossible. 81 ,, ,, ,, , width less than 1 n. mile. 82 ,, ,, ,, , width 1 to 3 n. miles. 83 ,, ,, ,, , width 3 to 5 n . miles. 84 ,, ,, ,, , width more than 5 n. miles. 85 Hummocked fast ice, no fur ther specification p ossible. 86 ,, ,, ,, , width less than 1 n . mile. 87 ,, ,, ,, , width 1 to 3 n. miles. 88 ,, ,, ,, , width 3 to 5 n . miles. 89 ,, ,, ,, , width more than 5 n . miles.
N o t e : ·when more than one number _is applicable the highest number should always be repor ted._
\
37
C ODE ,,ICE 02 " .
DIRECTION OF ICE-DRIFT (D. ).
Cod e f igure 0 No drift. 1 Ice-drifting from NE towards SW. 2 E
" W.
3 SE NW. 4
" s N.
5 SW " . NE. 6
" w
" E.
7 NW SE. 8
" N S.
CODE ,,ICE 03 ".
DIRECTION TO OPEN WATER OR WATER-SKY (d0).
Code f igure 0 No open water or water-sky. 1 Open water or water-sky in NE. 2
" " " " E.
3 "
SE. 4
" " s.
5 "
SW. 6
" " w.
7 "
NW. 8
" " " " N.
9 " "
most directions.
CODE ,,ICE 04 " .
POSSIBILITY OF NAVIGATION FOR STEAM OR MOTOR SHIPS (J).
Code f igu re 0 1 2 3 4
5 6 7 8 9
Navigation unimpeded. Navigation easy. Navigation difficult for ships with weak power. Navigation possible for powerful ships only. Navigation possible only for ships which are specially constructed for navigation in ice. Shipping maintained by means of ice-breaker. Navigation possible through lead or leads in the ice. Shipping temporarily closed. Shipping definitely closed. Possibility of navigation unknown owing to poor visibility.
38
Code f igme 0 1 2 3 4 5 6 7 8 9
Code figur e
0 1 2 3 4 5 6 7 8 9
Co de figure 0 1 2 3 4 5 6 7
CODE ,,ICE 05 ". EXTENT OF THE PART OF THE SEA WHICH IS COVERED
BY ICE (S0
) .
No ice. Traces of ice. 1 tenth covered by ice. 14 112 % 9 tenths ,, ,, ,, . Nearly covered by ice but some openings or narrow lanes present. Completely covered by ice. Observation impossible owing to fog or drifting snow.
CODE ,,ICE 06 " . THICKNESS OF THE ICE (u).
No ice. Ice crystals. Young ice, thickness less than 4 cm. Thin ice, thickness 4 to 8 cm. Thin ice, thickness 9 to 15 cm. Ice thickness 16 to 40 cm.
" "
No drift.
41 cm to 1 metre. 1 to 2 metres. 2 to 3 more thar:_' 3 ~etres.
C ODE ,,ICE 07 ". SPEED OF ICE-DRIFT (v e) .
Drif t not perceptible. Drift barely perceptible. Slow drif t (less than 0.5 n. miles per hour ) . Ordinary drift (0.5 to 1 n. mile per hour ) . Rapid drift (1 to 2 n. miles per hour ). Very rapid drift (more than 2 n. miles per hour ). Ice pressing against shore.
39
B. REGIONAL CODE FOR ICE MESSAGES.
Some countries of Northern Europe transmit during the winter time ice messages, containing information regarding· the ice conditions.
The general form taken can most simply be indicated thus:
A ~ J,J,' J ,J,' J,J,' J,J,' .. .. .. J,J,' 2 ~ bb J,J,' BB
J,J,' J,J,'
J,J,' ...... J,J,' 3 ~ cc cc
J,J,' J,J,' ...... J,J,' etc.
Meaning of the symbols :
1 2 3 Groups of stations in a fixed order (Estonia).
aa bb cc Groups of stations in a fixed order (Poland).
AA BB cc Groups of maritime regions, parts of the sea, harbours . etc.
J,.J/ Information referrino· to either of the stations in the order in which they fig-ure in the groups 1 2 3 ...... aa bb cc ...... AA BB CC ..... .
Codes for J 1 and J,' .
J ,. ICE CONDITIONS.
0 Clear of ice. l Close slush and new ice. 2 F'ixed sheet of ice. 3 Drift ice. 4 Close packed sludge or field ice. 5 Rift in the ice parallel to the coast. 6 Thick covering of ice. 7 H eavy drift ice. 8 Packed ice. 9 Screwed ice. x No information.
40
J/. EFFECT ON NAVIGATION.
0 Navigation unobstructed. 1 Navigation unobstructed for steamers; difficult for sailing ships 2 Navigation difficult for low powered steamers; closed to sailing
ships. 3 Navigation possible only for powerful steamers. 4 Navigation possible only for steamers constructed to withstand
ice pressure. 5 Navigation maintained with the assistance of ice-breaker. 6 Channel open in the solid ice. 7 Navigation temporarily closed. 8 Navigation closed. 9 Navig·ation conditions unknown owing to bad weather. x No information .
INTERNATIONAL CODES AND FORMS OF CODES FOR THE TRANSMISSION OF \'\TEATHER REPORTS.
ANNEXES.
I. Table for symbols for use on charts.
II. Table for conversion of degrees Fahrenheit and degrees Celsius.
III. Table for converting barometric readings in millimeters into millibars.
IV. Table for converting barometric readings in inches into millibars.
42 ANNEX I.
TABLE OF SYlUBOJ,S FOR USE ON CHARTS.
( 'ille symbols comform with tire amended specifica#ons of Res. 3g, 4r, 42, 43 and with t!te new symhols proposed in Res. 66 of Warsaw.)
'l'able 1. Symbols for Standard and Large Scale Charts.
WW 0 1 2 3 4 5 6 7 8 9 w N CL CM CH c E a 00 - - = ~ < - ( ) - D /' 0 - -
10 I~ 1CRl ( (-5>) 1)7 /\ A )( IX IX C>< Q .L. ____, / 0 / 1 20 ~ J •] ·] *] ~] ~] ~] ~] R] TI] 0 d. ~ L!. [;] / 2 30 @ -s.,.I ~ I~ ~ EB + * + =¥- -£~ ;;+ B VJ ---;> G' Cl 3 40 @ J -=] - -1 --1 -- - 1- - I - - - 0- 0 / v ~ ./ 4 - --,- - - 1-
50 0 ' ' ' ' • ' <:0 .L. El 'v 5 ' " ' '' ' ,, ,= ' • ' ....., ,__
' ' ' 60 8 • • • • ·- • t ('-"'\ ..,? [!] \_ 6 • •• • •• -* • - - - -v-• •• • • .- * 70 0 * * ~ ""*
- -...r fu d. El "'-> 7 * ** - A ....... * 2-.1:
* ** * ¥ "* Q
80 ~ 0 • v * .j(c ~ * {;,. {;,. 0 M ---" Q ~ 8 I/ 'fj 'fj I/ "\/ I/ v "\/ \J -v-
90 ® ~· R]* 1% A
~ A % R .a. K a 0 ~ B 00 ~ 9 R f.) TI
The ve rtic al st roke means uhas increase d" if placed before a symbol1
and )} has decreased'' if place d after a symbol.
The sign 0 me:rn s ,,w ithin s ight of the station'' . The sign 1 means that the phenomenon has beeu observed within the last hour but is not
occurring at the time ot observation. In 21, 41, 91, etc. the bracket s ign may be omitted where th e time of occurrence is clear from
the position of the symbol on the chart. In 42 th e space be tween the middl e and bott om lines should be black from the left for
approximately one half of the whole length. In 43 etc. th e opening in the horizontal s trok e should be about on e- third of the lengt,h, i.e. equal
to each of the short s troke s . In 30 , 40, etc. th e circle may be omitted if desired. The diameter of the circle (or do t ) in the symbol' (50 etc.) should not exce ed one half the diameter
of the symbol • (60 e tc.) . In 23, 70, 71 , . , 80, 90, e tc. th e horizontal s trok e is to be c learly shorter than the horizontal
stro ke in 41, e tc. In 101 20, 80, 93, 95, 97 use e ither • or ·~<- unl ess in doubt. In 25) 80, etc. the angle a t th e lower point of the shower symbol must be smaller than the other
two angles , i e . it must be appreci ab ly less th an 60°. In 27, 881 89, 94, 96, 99 the angles of the hail symbol are 60°; the angles in 78 are also 6QO, In ww = 56, 66 or 76 the elementa ry s igns ' 1 • or * shall be arranged in form of a rhomb, the
vert ical diagonal 01 which is clearly longer than the horizontal Qne . Principle H . Symbols in series horizontally denote s ,.sequence". Principle V. Symbols in series Yertically denotes .,Co ·existence".
[Symbols superposed d enot e uCo- ex istence11.]
N.B. Symbols for N have not yet b ee n decid ed. Symbols for ww = 00, 01 , 02, 03 and for W = O, 11 2 are also not decid ed.
Note: The re are a t present in use different systems of symb ols for N bu t mainly the two followin g sys tems:
N () 1 2 3 4 5 6 7 8 9
Sy mbol' l ~ ~ CD ~ () a 0 8 • ®
e:> e:> 0 QI) q[) ® ® (J]JP ®·
43
Scheme of Arrangement of Information arouml the Position of the Station.
CH (El TT CM PPP Vww ® tppa T5 T5 CLNh WCw) T, T1 h (RR)
Station Model.
S tation Jl1odei. The circle denc.ites the position of the station l>t tlte Station Model tlu letters llave the Joi/owing customary meanings :
PPP = Pressure. pp = Tendency . TT = Temperature. T1T 1 = Sea Temperature . ww = Present Weather. \V = Past Weather. a = Characte ri stic. E = State of Ground. CLCMCH = Form of Low, Medium and High Cloud. T 5 T 5 = Dew Point Temperature. N = Total Amount of Cloud . V = Visibility. Nh = Amount of Low Cloud. RR = Rainfall. h = Height of Low Cloud.
Also (w) = That part of ww which refers to the last hour but not to the time of obse rvation U = Humidity is alternative to T 51'5 .
Where lack of space necess itates a mo<iification ol the Station Mod el a defn1mation of it with out permutat ion of t h e places allotted to the individual elements. is permissib le .
1 f only one colour is used ic should be b lack.' If two colours, black and red, are used then red should b e used for one or more of the following:
( ! ) For Ctt (2) F or W (P as t Weather) (3) For TT, T 5 Ts (4) Fo r V (5 ) For pp when pp is negative.
Red should 1101 be used for PPP, ww, CM, CL, T1T 1, Nh , h.
'!'able 2. Abridgeil Symbols for Smaller Scale 'l'able 3. Abridged Symbols fo1· Cha1·ts. Newspaper Weather Charts, etc.
lwlA 0 1 2 3 4 5 6 7 8 9 w CL CM CH ~w 0 1 2 3 4 5 00 - 00 ~ <= (=) 0 00 - 00
10 ~ (* (R) (-5>) lj7 /\ A ir rx rx IX 1 Q L. _, 10 l.X R -5> w I\ A 20 I~ ·] ·] *l ~] vl ~l ~] R] 2 E::, ~ ~ 20 IX fX rx rx fX rx 30 -£+ + 3 1U B ...,,._, ---, 30 -£+ 40 =J - 4= 0 <:' ./ - -- 40 = IXIX 50 , :::!::: . 5 ~ <:::, ,_ , 50 ,
60 . - ; 6 . --- )""( ...--" • 60 . 70 * -
* - 7 * 0 c;;; 2-t 70 * 80 1%1 .
~ ~ ~ "' 8 ~ M -" 'i/ 'i/ \1 80 \1
90 R R}RJ~1H~ft M -s. ... 9 R ~ c d, RR 90 K . *
Table 4. Symbols for Fronts.
Oharacte·r of .frnnt on 1-Vorkiny Ch(trts on Printed Charts.
Cold front at the Con tin nous blue line • • • ground Cold front above Broken bi ne line """'" 'V' 'V'
the ground \Varm front at the Continuou s red line • • • ground Warm front above Brok en red line 0 0 c
the ground Occluded front at Continuous purple lin e -... ... ...
the ground Occluded front Broken purple line 0 .6. 0 ~
above the ground
Areas of tropical air Continuous red area Dotted area Areas of fog Continuous yellow area Distributed fog symbols
6 7 8 9 e < = -JrlX IX rx
rx rx rx IX +
----- . ---- * --- * -
K
Direction of Motion of
Fronts ·
t
t
t
t
44
I
ANNEX II.
TABLE FOR CONVERSION OF DEGR>EES FAHRENHEIT AND DEGREES CELSIUS.
OF I
oc I OF I
cc I OF I
oc I OF I
oc
-60 - 51.1 -20 -28.9 20 - 6.7 60 15.6 - 59 - 50.6 -19 - 28.3 21 - 6.1 61 16.1 - 58 - 50.0 - 18 - 27.8 22 -5.6 62 16.7 -57 - 49,4 -17 - 27.2 23 -5.0 63 17.2 -56 - 48.9 - 16 -26.7 24 - 4.4 64 17.8
- 55 - 48.3 -15 - 26.1 25 -3.9 65 18.3 - 54 - 47.8 -14 - 25.6 26 - 3.3 66 18.9 - 53 - 47.2 -13 -25.0 27 - 2.8 67 19.4 - 52 - 46.7 -12 - 24,4 28 - 2.2 68 20.0 - 51 - 46.1 -11 -23.9 29 -1.7 69 20.6
- 50 -45.6 -10 - 23.3 30 -1.1 70 21.1 - 49 - 45,0 - 9 - 22.8 31 -0.6 71 21.7 - 48 -44.4 - 8 -22.2 32 o.o 72 22.2 -47 - 43.9 - 7 - 21.7 33 0.6 73 22.8 -46 -43.3 - 6 -21.1 34 1.1 74 23.3
- 45 - 42.8 - 5 - 20.6 35 1.7 75 23.9 -44 - 42.2 - 4 - 20.0 36 2.2 76 24.4 -43 -41.7 - 3 -19.4 37 2.8 77 25.0 -42 - 41.1 - 2 -18.9 38 3.3 78 25.6 - 41 - 40.6 - 1 - 18.3 39 3.9 79 26.1
- 40 -40.0 0 -17.8 40 4.4 80 26.7 -39 - 39.4 ] -17.2 41 5.0 81 27.2 -38 - 39.9 2 -16.7 42 5.6 82 27.8 - 37 -38.3 3 -16.1 43 6.1 83 28.3 -- 36 - 37.8 4 -15.6 44 6.7 84 28.9
-35 - 37.2 fo -15.0 45 7.2 85 29.4 - 34 - 36.7 6 -14.4 46 7.8 86 30,0 - 33 - 36.1 7 -13.9 47 8.3 87 30.6 - 32 - 35 .6 8 -13.3 48 8.9 88 31.1 - 31 - 35.0 9 -12. 8 49 9 .4 89 31.7
-30 - 34.4 10 -12.2 50 10.0 90 32.2 -29 - 33.9 11 - 11.7 51 10.6 91 32.8 -28 -33.3 12 -11.1 52 11.1 92 33.3 - 27 - 32.8 13 - 10.6 53 11.7 93 33.9 - 26 - 32.2 14 - 10.0 54 12.2 94 34.4
-25 - 31.7 15 - 9.4 55 12.8 95 35.0 -24 - 31.1 16 - 8.9 56 13.3 96 35.6 - 23 - 30.6 17 - 8.3 57 13.9 97 36.1 - 22 -30.0 18 - 7.8 58 14.4 98 36.7 -21 -29.4 19 - 72 59 15.0 99 37.2
I
Milli-metres
250 260 270 280 290
300
310 320 330 340
350
360 370 380 390
400
410 420 430 440
450
460 470 480 490
500
510 520
I
530 540
550
560 570 580 590
600
610 620 630 640
650
660 670 680 690
700
710 720 730 740
750
760 770 780 790
800
ANNEX III. TABLE FOR CONVERTING BAROMETRIC READINGS IN
MILLIMETRES INTO MILLIBARS.
.o I .1 I .2 I .3 I .4 I .5 I .6 I .7 I .8
Millibars
333.3 334.6 336.0 337.3 338.6 340.0 341.3 342.6 344.0 346.6 348.0 349.3 350.6 352.0 353.3 354.6 356.0 357.3 360.0 361.3 362.6 364.0 365.3 366.6 368.0 369.3 370.6 373 3 374.6 376.0 377.3 378.6 380.0 381.3 382.6 384.0 386.6 388.0 389.3 390.6 392.0 393.3 394.6 396.0 397.3
400.0 401.3 402.6 404.0 405.3 406.6 408.0 409.3 410.6
413.3 414.6 416.0 417.3 418.6 420.0 421.3 422.6 424.0 426.3 428.0 429.3 430.6 432.0 433.3 434.6 436.0 437.3 440.0 441.3 442.6 444.0 445,3 446.6 448.0 449.3 450.6 453.3 454.6 456.0 457.3 458.6 460.0 461.3 462.6 464.0
466.6 468.0 469.3 470.6 472.0 473.3 474 .6 476.0 477.3
480.0 481.3 482.6 484 0 485.3 486 6 488.0 489.3 490.6 493.3 494.6 496.0 497.3 498.6 499.9 501 3 502.6 503.9 506.6 507.9 509.3 510.6 51 1.9 513.3 514.6 515.9 517.3 519.9 521.3 522.6 523 .9 525.3 526.6 527 .9 529.3 530.6
533.3 5::14 .6 535.9 537 .3 538.6 539.9 541.3 542.6 543.9
546.6 547.9 549.3 550.6 551.9 553.3 554.6 555.9 557.3 559.9 561.3 562.6 563.9 565.3 566.6 567 .9 569.3 570.6 573.3 574.6 575.9 577.3 578.6 579.9 58 1. 3 582.6 583.9 586 .6 587.9 589.3 590.6 591.9 593.3 594.6 595.9 597.3
599.9 601.3 602.6 603.9 605.3 606.6 607.9 609.3 610.6
613 .3 614.6 615.9 617 .3 618 .6 619.9 621.3 622.6 623.9 626.6 627 .9 629.3 630.6 63 1.9 633.3 634.6 635.9 637 .3 639.9 641.3 642.6 643.9 645 .3 646 .6 647.9 649.3 650.6 653.3 654.6 655.9 657.3 658.6 659.9 66 1.3 662.6 663.9
666.6 667.9 669.3 670.6 671.9 673.3 674.6 675.9 677 .3
679.9 681.3 682.6 683.9 685.3 686.6 687.9 689.3 690.6 693.3 694.6 695.9 697.3 698.6 699.9 701.3 702.6 703.9 706.6 707 .9 709 .3 710.6 71 1.9 713.3 714.6 715.9 717.3 719.9 721.3 722.6 723.9 725 .3 726.6 727.9 729.3 730.6
733.3 734.6 735 .9 737.3 738.6 739.9 741.3 742.6 743.9
746,6 747.9 749.3 750.6 751.9 753 .3 754.6 755.9 757.3 759.9 761.3 762.6 ' 763.9 765.3 766 .6 767.9 769.3 770.6 773.3 774 .6 775.9 777 .3 778.6 779.9 781.3 782.6 783.9 786.6 787.9 789.3 790.6 791.9 793.3 79'4.6 795.9 797.3
799.9 801.3 802.6 803.9 805.3 806.6 807.9 809.3 810.6
813.3 814.6 815.9 817.3 8 18.6 819.9 82 1.3 822.6 823 .9 826.6 827.9 829.3 830.6 831.9 833.2 834.6 835.9 837.2 839.9 841.2 842.6 843.9 845 .2 846.6 847.9 849.2 850. 6 853.2 854 .6 855.9 857.2 858.6 859.9 86 1.2 862.6 863.9
866.6 867.9 869.2 870 6 871.9 873.2 874.6 875.9 877.2
879.9 88 1.2 882.6 883 .9 885 2 886.6 887.9 889.2 890.6 893.2 894.6 895.9 897.2 898.6 899.9 901.2 902.6 903.9 906.6 907.9 909 .2 9 10.6 911.9 913.2 914.6 915.9 9 l 7.2 919.9 921.2 922.6 923.9 925.2 926.6 927.9 929.2 930.6
933,2 934.6 935.9 937.2 938.6 939.9 94l.2 942.6 943.9
946.6 947.9 949.2 950.6 951.9 953.2 954.6 955.9 957.2 959.9 961.2 962.6 963 .9 965.2 966.6 967 .9 969.2 970.6 973 2 974.6 975.9 977.2 978.5 979.9 981.2 982.6 983.9 986,6 987,9 989.2 990,6 991.9 993.2 994 .6 995.9 997.2
999.9 1001.2 1002.6 1003.9 1005.2 1006.6 1007.9 1009.2 1010.6
1013.2 1014.6 1015.9 1017.2 1018.6 1019.9 1021.2 1022.6 1023.9 1026.6 1027.9 1029.2 1030.6 1031.9 1033.2 1034.6 1035.9 1037.2 1039.9 1041.2 1045.2 1043.9 1045.2 1046.6 1047.9 1049.2 1050.6 1053.2 1054.6 1055.9 1057.2 1058.6 1059.9 1061.2 1062.6 1063.9
1066.6
45
I .9
345 3 358.6 372.0 385.3 398.6
412.0
425.3 438.6 452.0 465.3
478.6
492.0 505.3 518.6 53 1.9
545.3
558.6 571.9 585.3 598.6
611.9
625.3 638.6 651.9 665.3
678,6
691.9 705.3
718.6 1 731.9
745.3
758.6 771.9 785.3 798.6
811.9
825.3 838.6 851.9 865.2
878.6
89 1.9 905.2 918.6 93 1.9
945.2
958.6 971.9 985.2 998.6
1011.9
1025.2 1038.6 1051.9 1065 .2
46 ANNEX IV. TABLE FOR CONVERTING BAROMETRIC READINGS IN INCHES
INTO MILLIBARS.
.00 .01 .02 .03 .04 .05 .06 .07 .08 .09 Inches I I I I I I I I l
Millibars
27.0 914.3 914.6 915.0 915.3 915.7 916.0 916.3 916.7 917.0 917.4 27.1 917.7 918.0 918.4 918. 7 919.0 919.4 919.7 920 1 920.4 920.7 27.2 921.l 9'21.4 921.8 922. 1 922.4 922.8 923 .1 923.4 923.8 924.1 27 .3 924.5 924 .81 925.1 925.5 925.8 926.1 926.5 926.8 927.2 927.5 27.4 927.9 928.2 928.5 928.9 929.2 929 .5 929.9 930.2 930.6 930.9
27.5 931.2 931.6 931.9 932.3 932.6 932.9 933 .3 933.6 933.9 934 .3 27.6 934.6 935.0 935 .3 935 .6 936.0 936.3 936 .7 937.0 937.3 937.7 27. 7 938.0 938.3 938.7 939.0 939,4 939.7 94 0.0 I 940,4 940.7 941.1 27.8 94 L4 941.7 942.1 942 .4 942.8 943.1 943.4 943 ,8 944.1 944.4 27.9 944.8 945.1 945.5 945.8 946.1 946.5 946.81 947.2 947.5 947.8
28.0 948.2 948.5 948.8 949 2 949.5 949.9 950.2' 950. 5 950.9 I 951.2 28.1 951.6 951.9 952.2 952.6 952.9 953.2 95-3.6 953.9 954.3 954. 6 28,2 954.9 955.3 955.6 956. 0 956.3 956.6 957.0 957.3 957.7 958,0 28.3 958.3 958.7 959.0 ' 959.3 959.7 960.0 960 .4 960.7 96 1.0 961.4 28.4 961.7 962.1 962.4 962.7 963.1 963.4 963 ,7 964.1 964.4 964.8
28.5 965.1 965.4 965.8 966. 1 966.5 966.8 967.1 967.5 967.8 968.1 28.6 968.5 968.8 969.2 969.5 969.8 970.2 970.5 970.9 971.2 971.5 28.7 971.9 972.2 972.6 972.9 973.2 973.6 973.9 974.2 974 .6 974.9 28 .8 975 .3 975.6 975.9 976.3 976.6 977.0 977 .3 97 7.6 978.0 978.3 28.9 978.6 979.0 979.3 979.7 980 .0 980.3 980 7 981.0 981.4 981.7
29.0 982.0 982.4 982.7 983 .0 983.4 983.7 98 4.l 984.4 984.7 985. l 29.1 985.4 985.8 986. 1 986.4 986.8 987.1 987.5 987 8 988.1 988.5 29,2 988.8 989.1 989.5 989.8 990.2 990.5 990 8 991.2 991.5 991.9 29.3 992.2 992.5 992.9 993.2 993.5 993 .9 994.2 994.6 994.9 995.2 29.4 995.6 995.9 996.3 996,6 996.9 997 .3 997.6 997.9 998.3 998.6
29.5 999.0 999.3 999.6 1000. 0 1000.3 1000.7 1001.0 1001.3 100 1.7 1002.0 29.6 1002.4 1002.7 1003.0 1003.4 1003.7 1004.0 1004.4 1004.7 1005.1 1005.4 29.7 1005.7 1006.1 1006.4 1006.8 1007, l 1007.4 1007 .8 1008.1 1008.4 1008.8 29.8 1009 .l 1009.5 1009.8 1010.1 1010.5 1010.8 1011.2 1011.5 11011.8 1012.2 29.9 1012.5 10 12.8 1013.2 1013.5 1013.9 1014.2 1014.5 1014.9 101 5.2 1015,6
30.0 1015.9 1016.2 1016.6 1016.9 101 7.3 101 7.6 101 7.9 1018.3 1018.6 1018.9 30,l 1019.3 1019.6 1020.0 1020.3 1020,6 1021.0 1021.3 1021.7 1022.0 1022.3 30.2 1022.7 1023.0 1023.3 1023 .7 1024.0 1024.4 1024. 7 1025. 0 1025.4 1025. 7 30.3 1026.1 1026.4 1026.7 1027 , 1 1027 .4 1027. 7 1028 .l 1028.4 1028 8 1029.1 30.4 1029.4 1029.8 1030.1 1030.5 1030.8 103 1.1 11131.5 1031.8 1032.2 1032.5
30.5 1032.8 1033 2 1033.5 1033.8 1034.2 1034.5 1034.9 1035.2 1035.5 1035.9 30.6 1036.2 1036.6 1036.9 1037 .2 1037.6 1037 .9 1038.2 1038.6 1038 .9 1039.3 30.7 1039.6 1039.9 1040.3 1040.6 1041.0 1041.3 1041.6 1042.0 1042.3 1042.6 30.8 1043.0 1043.3 1043.7 1041.0 1044.3 1044.7 1045.0 1045.4 1045 .7 1046.0 30.9 1046.4 1046.7 1047. 1 1047 .4 1047.7 1048.1 1048,4 1048.7 1049.1 1049. 4
SECRETARIAT DE L'ORGANISATION METEOROLOGIQUE INTERNATIONALE.
INTERNATIONAL CODES AND FORMS OF CODES FOR THE TRANSMISSION OF WEATHER REPORTS.
Supplement no. 1. 30th December, 1937.
page 4 - Reports of upper winds - Add note 1) with the following
text:
' ) From lst January, 1938, countries in Europe may use the new Upper Wind Code : IIIGG HHddv
5 ......... (CLCMHHM) 44444 m
1m
2m
3m
4m
5 m
6m
7xxx
. .. .. . . .... .. ~ · · ·· ·· - · ··· · ·~· · · · · ·· - · .. · · · ·· ' . ......... . ... . ..... " •• , ........... . ............. ~ ....... , •• ,. •• J Forms of codes ns . 13 and 14 - Replace 00000 after (iii) by 99999.
page 7 - Transmission of monthly mean values of meteorological elements - Add :
' &. • ,. & a• '"I .• • t • e e. ,. • • • • t • _,, It 4' • •A -4-. ~ (l ""' ) 'I ,_ t' f • • • • • I ,\ . •I I I ' I w • • • • • it, • f it I I it • .... •at A• ... ff • t •I ate e e •
The figures PP give the units and tenths in millibars for the regions between the latitudes 20° N and 20° S and the tens and units for t he other stations.
The line above the symbolic letters signifies : ,,mean value'' .
. ... ,.. .. .. .... ,_ . . .... .... .. ... .. ..... <: .. .. . .. ~ · •• • .. . .... " "" ' . ... r e ..... . ....... ~ .. ...... . ........... ., .... . . ... .... '# ~ ~ ~ ··-···•-•1 pages 8-12:
dd - Add: If f" • ., .f t t t • • t • :oi 1r • " ~ w • w " , 1 • " II\. f <l 1 ' .. ' ,, .- .a. C t 11 t • r· 1r • ; .,. •' • ;. t1 I .. I ft" ( 4 ' a • 'f' ., t. ••I I 6 tt ~ i .. ., • f •I f " • • • f "" ,_ we ~ •
In the new P ilot Code IIIGG HHddv 5 a calm wind is expressed by v 5 = 0 and dd = 00. If the value of the wind is 50 k/hr 1 ) or more the figures for dd should be increased by the addition of 50. (See for details v 5 .) (Res. 45 of Salzburg.)
' ) The round figure is 50 k/hr, the exact figure is 48 k / hr . . • If " ' • - • ' • •••• c " ••• •-... I. (I ~ f Ill "'. , , - • ~ _, I ' f rt- , ' .. . ... I ... { ••••• .,. " .. ' "~ . .. ,. •• ' "t • t ~ , • ,, •• f. c •• ~ ..... ~ • ,, .... .
HH Height in hectometres above sea Jevel to which observations of upper wind refer. (Res. 45 of Salzburg.)
A 5-figure group should b e given for each lev·el ai which a definite change of wind b egins. 'l'he values should be given for the first byer inside the new regime of wind. The values sh ould also be given for 1000 ancl 2000 metres a,bove sea level, when possible. For international exchange it will usually be sufficient to give about 5 groups. In general, values of dclv, should refer to a layer of ,about 200 1
) metres ancl HH should r efer to Lhe centre o.f this layer. Thus, when HH := 20, the wind will refer to a layer centred at 2000 m above sea level.
1) If it is clear from the ascent that the value from a 200 m layer
is misleading the value should b e taken from a thicker layer.
HH Height in hectometres above sea level of the last observation of the balloon given in the additional group CLCMHHM.
..................................................................•........•••.....•.••.. . M -Reason for the ending of the observation of the pilot balloon.
(Res. 47 of Salzburg.) See Code 53. Speed of the wind in the upper air at height HI-I. (Res. 45 of Salzburg.) See Code 36.
If the value of the wiwd is 50 k/hr ') or more the figures for dd should be increased by the addition of 50 and th e values v,- 50 coded in the message. In that case, the value of v,_ when decoded from the message is also increased by the addition of 50.
If the wind is 100 k / hr 1 ) or more the wind in the group is given without the 100 's figure, i.e. for a wind of 113 k/hr the figure for v, would be 3. In this case an index group 44444 is added at the end of the message, fo llowed by a group or groups of the form m,m,m,m.m, m,m,xxx, where m gives the lOO's figure in the speed of the wind for the conesponding group in the message, i.e. if the speed in th e four.th gi'oup of the message 113 k/hr, m, would be 1. For groups in which the speed is less t h an 100 k/hr the corresponding m = 0. If there are less than five m 's in the last group ·of figures, this m-group is made into a 5-figure group ·by the addition of x 's.
') The l'Ou nd figure is 50 k/hr and 100 k/hr. 'l'he exact figure . is 48 k/hr and 98 k/hr. See Code for v,.
········································· ~ ················································ page 13 - Add:
page 19 - Add :
36-V-53 - lVi.
.••..........•..•..••••..........•..•.•................................................... CODE 36.
SPEED OF THE WIND IN THE UPPER A IR AT HEIGHT HH (v,).
(dd=01-36) (dd=51-86) Code figure Spee cl Code figure Speed
0 0- 2 k/hr 0 48 - 52 k/hr 1 3- 7 1 53 - 57 2 8-12 2 58-62 3 13 - 17 3 63 - 67 4 18-22 4 68-72 5 23-27 5 73 - 77 6 28-32 6 78 - 82 7 33-37 7 83 - 87 8 38-42 8 88 - 92 9 43 -47 9 93 -- 97
• rtv111••• ~ •••~t••••• ~ ·••• r •lttt••.,•••••~• • , • lt ••••••~•••t••••••••••••••r••••••••t•••••••••
page 21 - Add:
, ( • l" f' • e f •I. • ~ N • f ( f' • • • • • 4 •· . ~ ..... I .. I ' C ff ~ f 4 I '' • "I t t It I I • f' t. •I.(' •. f It a I • ... t It Pt• t f •I et I I I. t. f" I •• • e
CODE 53. REASON FOR THE ENDING OF THE OBSERVATION OF THE
PILOT BALLOON (M) .
Cod·e figure
0 observation abandoned 1 obscured by passing clouds 2 balloon burst 3 lost in haze 4 lost near the sun 5 entered cloud layer
Cod·e figure
6 lost accidentally 7 obscured by rain 8 confused with star 9 for use when none of the above
apply
, ..........................•........•.......•.......... ....... ...... ........ ..............