2005 tropical weather impacts to the memphis cwa

2005 Tropical Weather Impacts to the Memphis

CWA

2005 Tropical Weather Impacts to the Memphis

CWAJonathan L. Howell – Jason F. Beaman

National Weather Service - Memphis, TN

Jonathan L. Howell – Jason F. Beaman

National Weather Service - Memphis, TN

Memphis Tropical ImpactsMemphis Tropical Impacts• Overview of Impacts From Hurricanes

Katrina & Rita

– Satellite, Radar, & Track Overviews

– Synoptic Weather Patterns Responsible for Steering of Tropical Systems

– Mesoscale Weather Environments

• Katrina – Pressure Gradient Winds

• Rita – Convective/Severe Weather Environment

– Impacts to Memphis County Warning Area

– WFO Operations Performance

• Overview of Impacts From Hurricanes Katrina & Rita

– Satellite, Radar, & Track Overviews

– Synoptic Weather Patterns Responsible for Steering of Tropical Systems

– Mesoscale Weather Environments

• Katrina – Pressure Gradient Winds

• Rita – Convective/Severe Weather Environment

– Impacts to Memphis County Warning Area

– WFO Operations Performance

Hurricane KatrinaHurricane Katrina

Hurricane Katrina’s TrackHurricane Katrina’s Track

Katrina Weather ImpactsKatrina Weather Impacts

• Weather Impacts to North Mississippi

– 7 Hours of Tropical Storm Force Wind Gusts (22z-06z) at Tupelo, MS ASOS (KTUP)

– Maximum Gust – 46 Kts. – KTUP – 2350z/0148z

– Unofficial Wind Gust Reports > 50 Kts.

– Lowest Pressure – 980 mb. – KTUP – 07z

– Rainfall Amounts Ranged Between 4”-8” Isolated Higher

– Rain Gauge Measurements of 3”-6” Underestimated Actual Totals Due to High Winds

• Weather Impacts to North Mississippi

– 7 Hours of Tropical Storm Force Wind Gusts (22z-06z) at Tupelo, MS ASOS (KTUP)

– Maximum Gust – 46 Kts. – KTUP – 2350z/0148z

– Unofficial Wind Gust Reports > 50 Kts.

– Lowest Pressure – 980 mb. – KTUP – 07z

– Rainfall Amounts Ranged Between 4”-8” Isolated Higher

– Rain Gauge Measurements of 3”-6” Underestimated Actual Totals Due to High Winds

Katrina Damage Across Memphis CWA

Katrina Damage Across Memphis CWA

• Damage Across North Mississippi

– Structural Damage – Mainly Trees Falling on Structures

– Hundreds of Trees Downed/Uprooted

– Powerlines Downed – 100,000+ Customers Without Power

– Flash Flooding/Minor River Flooding

• Water Over Secondary Highways

• 5 River Points to Flood

– Buttahatchie / Tombigbee / Noxubee / Town Cr.

• Damage Across North Mississippi

– Structural Damage – Mainly Trees Falling on Structures

– Hundreds of Trees Downed/Uprooted

– Powerlines Downed – 100,000+ Customers Without Power

– Flash Flooding/Minor River Flooding

• Water Over Secondary Highways

• 5 River Points to Flood

– Buttahatchie / Tombigbee / Noxubee / Town Cr.

Katrina Weather ImpactsKatrina Weather Impacts• Weather Impacts to

West Tennessee

– Tropical Storm Force Wind Gusts at Memphis (KMEM) & Jackson (KMKL)

• 6 Hours at KMEM (03z-09z)

• 3 Hours at KMKL (05z-08z)

– Maximum Gust

• 47 Kts. – KMEM – 0641z

• 38 Kts. – KMKL – 0538z

– Unofficial Wind Gust Reports > 50 Kts.

– Lowest Pressures Recorded

• KMEM – 989 mb. (0653z)

• KMKL – 987 mb. (0953z)

– Rainfall Amounts Ranged Between 3-6 Inches

• Weather Impacts to West Tennessee

– Tropical Storm Force Wind Gusts at Memphis (KMEM) & Jackson (KMKL)

• 6 Hours at KMEM (03z-09z)

• 3 Hours at KMKL (05z-08z)

– Maximum Gust

• 47 Kts. – KMEM – 0641z

• 38 Kts. – KMKL – 0538z

– Unofficial Wind Gust Reports > 50 Kts.

– Lowest Pressures Recorded

• KMEM – 989 mb. (0653z)

• KMKL – 987 mb. (0953z)

– Rainfall Amounts Ranged Between 3-6 Inches

Katrina Damage Across Memphis CWA

Katrina Damage Across Memphis CWA

• Damage Across West Tennessee

– Minor Structural Damage

– Several Trees Downed/Uprooted

– Powerlines Downed – 77,000 Customers Without Power in Memphis/Shelby County

– Additional Power Outages Across Remainder West TN

– Flash Flooding/River Flooding

• Water Over Secondary Highways

• 1 River Point to Flood

– S.F. Forked Deer

• Damage Across West Tennessee

– Minor Structural Damage

– Several Trees Downed/Uprooted

– Powerlines Downed – 77,000 Customers Without Power in Memphis/Shelby County

– Additional Power Outages Across Remainder West TN

– Flash Flooding/River Flooding

• Water Over Secondary Highways

• 1 River Point to Flood

– S.F. Forked Deer

Hurricane RitaHurricane Rita

Hurricane Rita’s TrackHurricane Rita’s Track

The Difference Aspects of RitaThe Difference Aspects of Rita

• There were three significant meteorological impacts to the Mid-South

– Heavy Rain

– Tropical Storm Force Wind Gusts

– Severe Weather/Mesocyclone Development

• There were three significant meteorological impacts to the Mid-South

– Heavy Rain

– Tropical Storm Force Wind Gusts

– Severe Weather/Mesocyclone Development

Heavy RainHeavy Rain

Tropical Storm Force Wind Gusts

Tropical Storm Force Wind Gusts

• Numerous tropical storm wind gusts

– KMEM 38 kts @ 1309Z

– KTUP 48 kts @ 1725Z

– Other unofficial reports of 35 to 45 kt winds primarily over north Mississippi

• Gusts produced by convective downdrafts (50-55 dbz cores up to 10,000 feet)

• Numerous tropical storm wind gusts

– KMEM 38 kts @ 1309Z

– KTUP 48 kts @ 1725Z

– Other unofficial reports of 35 to 45 kt winds primarily over north Mississippi

• Gusts produced by convective downdrafts (50-55 dbz cores up to 10,000 feet)

Convective WindsConvective Winds

VAD Wind ProfileVAD Wind Profile

Concerns as Rita Approached the Mid-South

Concerns as Rita Approached the Mid-South

• Although Rita was a depression as it approached the Memphis CWA, it moved at a very favorable heading for producing tornadoes (010-040 degrees). (Malkin and Schulz, Jr., 1966)

• Forecasters at WFO Memphis were tracking many mesocyclones across Arkansas and central Mississippi. Would conditions be right for tornadoes to occur in the Memphis CWA?

• With this in mind, we’ll take a look at the mesoscale environment as Rita progressed into the Mid-South

• The focus will be on the morning of September 25th.

• Although Rita was a depression as it approached the Memphis CWA, it moved at a very favorable heading for producing tornadoes (010-040 degrees). (Malkin and Schulz, Jr., 1966)

• Forecasters at WFO Memphis were tracking many mesocyclones across Arkansas and central Mississippi. Would conditions be right for tornadoes to occur in the Memphis CWA?

• With this in mind, we’ll take a look at the mesoscale environment as Rita progressed into the Mid-South

• The focus will be on the morning of September 25th.

1844z SRM

1855z SRM

1906z SRM

1917z SRM

Rita DamageRita Damage

• Light to moderate damage across E AR, W TN, and N MS

• Damage confined to downed trees and power lines (mainly in N MS)

• 3 to 6 inches of rain caused road and isolated residential flooding

• Total damage estimated at $100K +

• Light to moderate damage across E AR, W TN, and N MS

• Damage confined to downed trees and power lines (mainly in N MS)

• 3 to 6 inches of rain caused road and isolated residential flooding

• Total damage estimated at $100K +

SummarySummary

• Katrina damage primarily from gradient winds

• Tropical storm wind gusts occurred well west of center

• Total Katrina damages in hundreds of thousands

• Damages to structures, trees, & power lines

• Katrina damage primarily from gradient winds

• Tropical storm wind gusts occurred well west of center

• Total Katrina damages in hundreds of thousands

• Damages to structures, trees, & power lines

Summary Summary

• Rita damage primarily from convective wind gusts

• Tropical storm force wind gusts occurred primarily in bowing line segments & mesocyclones

• Total Rita damages > $100K

• Damage mainly to trees and power lines

• Rita damage primarily from convective wind gusts

• Tropical storm force wind gusts occurred primarily in bowing line segments & mesocyclones

• Total Rita damages > $100K

• Damage mainly to trees and power lines