SANDY BRIEFING

Briefing Summary 8:30 AM Monday October 29, 2012

Hull – Oct. 1991 Courtesy of Boston Globe

National Weather Service Boston, MA

Impacts occurring across our region Surges have increased to 2 ft

overnight. Wind gusts have increased to 30-45 mph

National Weather Service Boston, MA

Wind gusts as of 7 AM

Overview

National Weather Service Boston, MA

• Sandy will cause MAJOR impacts to southern New England • Impacts:

• High seas 25 to 35 feet – highest south of New England • Prolonged destructive winds w/ widespread power

outages • Expect gusts of over 50 mph for 12-15 hrs straight

• Coastal flooding: • Severe along south coast • Moderate along east coast

• Severe beach erosion • Heavy rain / flooding - West

WATCHES/WARNINGS IN EFFECT • High Wind Warning for all land areas of Southern

New England • Coastal Flood Warning all of MA and RI coastline • Flood Watch for

– Southwest NH – Central and western MA – Northern CT

• Marine – Hurricane Force Wind Warning (south coastal waters,

including Cape Cod Bay) – Storm Warning (coastal waters north of Cape Cod and

Narragansett Bay)

National Weather Service Boston, MA

5 am NHC Update

Hurricane Sandy • Status:

• Location:

• Movement:

• Pressure:

• Comments:

• Forecast:

Hurricane-forced winds are expected along portions of the coast between Chincoteague, VA & Chatham, MA

Cat 1 Hurricane – 85 mph

368 miles south of B.I.

North at 15 mph

946 mb (27.94 inches)

Start moving towards the Mid-Atlantic

Marine Impact

National Weather Service Boston, MA

• Dangerous and Potentially Life Threatening Seas – Peaking out today into the

evening – Seas 25 to 35 feet highest

south of New England • Wind across southern New

England coastal waters – Hurricane force (either

sustained or gusts), mainly from Provincetown to Block Island).

– Strongest 11 am – 8 pm. – Diminishing to Gales on

Tuesday

Wind • Damaging winds expected

– Interior: • 30 to 40mph with gusts 50 to

60 mph (less in valleys)

– Coastal plain: • 40 to 50 mph with gusts 60 to

80(+) mph

• Widespread power outages especially where trees still have foliage

National Weather Service Boston, MA

LEADING EDGE OF GUSTS OVER 50 MPH Monday October 29

9 AM

9 AM

11 AM

11 AM 2 PM

2 PM

60 TO 80(+) MPH

50 TO 60 MPH

Coastal Flooding • Coastal flooding and erosion for multiple tide cycles • South coast

– This morning & evening, & tomorrow morning high tides – This evening coastal flooding will be major New Bedford area (outside

hurricane barrier) to Westerly including Narragansett Bay • 4 to 6 foot storm surge possible – possibly 7 feet upper part of Narragansett Bay • Large and high energy waves could be destructive along ocean exposed shoreline (30 to

35 foot waves offshore) • East coast

– Probably mostly moderate today at midday and night (near midnight) high tides – 2 to 4 foot storm surge (worst case scenario 5 feet) during the midday Monday

high tide – Highest surge may occur during Monday evening low tide – Large and high energy waves will produce wave run-up, overwash, and splash

over (> 25 feet offshore) • Severe beach erosion both south and east coasts

National Weather Service Boston, MA

http://www.erh.noaa.gov/box/cfwGMdisplay.php

Heavy Rain/Flooding • Potential for 1 to 3 inches

Today thru Wednesday – Locally more possible higher

terrain

• Poor drainage flooding likely – Exacerbated by clogged

drains

• Small stream flood potential higher terrain areas

National Weather Service Boston, MA

NERFC Day 3 Day Total

Summary • Sandy will have major impact on southern New England - Very large storm – covering huge area • Dangerous Seas – 25 to 35 feet offshore (highest to south) • Serious coastal flood threat

– Major (even to point of destructive) Monday evening high tide along portions of south coast

• Most of RI south coast including Narragansett Bay • MA south coast from Westport to New Bedford area (outside hurricane barrier)

• Severe beach erosion likely both east and south coasts • Damaging winds – strong enough for widespread power outages • Bands of heavy rain with potential for localized more than 3 inches over

high terrain – Poor drainage flooding likely – Potential for small stream flooding Monday and Monday night

• Time frame of greatest concern: – Highest risk for coastal flooding and strongest winds will be Monday into

Monday night

National Weather Service Boston, MA

Questions? • Get the latest information at:

– www.weather.gov/boston • Area Forecast Discussion • Hazardous Weather Outlook

• Call us: 508-823-2228 • E-mail/Contact Point:

National Weather Service Boston, MA

Glenn.Field@noaa.gov (Today) Stephanie.Dunten@noaa.gov (Overnight)