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April 27-28, 2011 Southeast Tornado Outbreak

April 27-28, 2011• ~190 tornadoes, ~311 fatalities• Deadliest outbreak since March 21, 1932• Outlook issued 5 days prior; Moderate Risk issued 3 days in

advance; High Risk issued 16 hours in advance• Coordination calls initiated w/FEMA and state emergency

managers 3 days in advance • POD 96% for tornadoes occurring in SPC watches• Average warning lead time 24 min

10AM – 11PM CDT April 27, 2011 1

April 27-28, 2011Tornado Outbreak

Day 4-8

Day 4 – 12Z April 27- 12Z April 28, 2011

Day 5 – 12Z April 27- 12Z April 28, 2011

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ProbabilisticDay 3Categorical

CategoricalProbabilistic

April 27-28, 2011 Tornado Outbreak

Day 2

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Categorical

Day 1

High Winds

April 27-28, 2011 Tornado Outbreak

Hail

Tornado

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2011 Year-to-Date Tornado Statistics

• NWS’s preliminary estimates show approximately 1,653 tornadoes so far this year. – The previous yearly record number of tornadoes was

set in 2004 with 1,817.– The overall yearly average number of tornadoes for the

past decade is 1,274.

• The preliminary estimated number of tornado fatalities so far this year is 537, including 151 fatalities from the Joplin tornado. – 2011 is preliminarily the 6th deadliest

tornado year in U.S. history. 6

• A large portion of Joplin Missouri was devastated by an EF-5 (greater than 200 mph) tornado

• Over 150 fatalities and over 1000 injured

• Joplin tornado is deadliest since modern recordkeeping began in 1950

• Ranked 7th among the deadliest tornadoes in U.S. history.

• Storm Prediction Center highlighted southwest MO for the potential for severe weather three days prior to the day of the storm.

• Tornado watch issued 4 hours in advance

• Springfield, MO WFO issued a tornado warning with a lead time of 24 minutes

Joplin EF-5 Tornado – May 22, 2011

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• On June 1, 2011, a supercell thunderstorm developed over western Massachusetts.

• Produced an EF3 (160 MPH) tornado that cut a 39-mile (63-kilometer) track of destruction across southwest and south-central Massachusetts.

• Storm Prediction Center (SPC) issued severe weather outlook 5 days in advance .This area was maintained in the days leading up to the event.

• Tornado Watch issued 3 hours prior to the Springfield event.

• A Tornado Warning was in effect for the city of Springfield and surrounding area at the time of the storm.

Springfield, MA Tornado

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April 14, 2012 OK/KS Tornado Outbreak

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• Outlook first issued 7 days in advance; Moderate Risk 3 days in advance; High Risk 2 days in advance (only 2nd time)

• 60 Tornadoes (1 EF4, 3 EF3 & 3 EF2)• 6 Fatalities in Woodward, OK • No other fatalities• Large tornadoes near Wichita, El Dorado & Salina KS• Preliminary NWS average warning lead time

(Tornadoes) : 20.1 minutes.

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Day 7 – Issued April 8 Day 6 – Issued April 9

Day 5 – Issued April 10 Day 4 – Issued April 11

Valid Sat, April 14 – Sun, April 15, 2012

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Day 3 – Issued April 12 Day 2 – Issued April 13

Day 1 – Issued April 14

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Weather Ready Nation: A Vital Conversation

Workshop held in Norman, OK, December 2011

• Focus on the “last mile”: delivery of warnings• Assess and update warning dissemination strategy• Integrate social and physical science

– Is the message delivered equal to the message received– Impact-based Forecast and Warnings

• Improved outreach and education

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14 April 2012 Great Plains Outbreak

• 60 Tornadoes (1 EF4, 3 EF3 & 3 EF2)• Preliminary NWS average warning lead time (Tornadoes) :

20.1 minutes• 6 Fatalities in Woodward, OK near midnight• Outlook first issued 7 days in advance; Moderate Risk 3 days in

advance; High Risk 2 days in advance (only 2nd time)• FEMA/State/local emergency managers engaged starting 5 days

before the event

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14 April Great Plains Outbreak• “Anyone tuned into a television or weather

service last week would have been hard pressed to miss the news that dangerous storms were brewing in the Midwest. Clearly, these storms were meant to be taken seriously.” 

-- Kansas City Star

• “The Storm Prediction Center in Norman, Okla., which specializes in tornado forecasting, took the unusual step of issuing a stern warning about the oncoming storms more than 24 hours in advance.” 

-- Christian Science Monitor

• “I really think people took the warnings and they took them very seriously. We had more notice on this system than you normally do. You normally are looking at a couple of hours’ notice. Well, this one had almost two days’ notice.” 

-- Kansas Gov. Sam Brownback

• “We'd been on the lookout for it for three days. We were as ready as we could have been.” 

-- Larry Hill, Thurman , IA (AP) resident whose home was destroyed