March 25 th Severe Weather Event: Highlighting the difficulties we face as meteorology, and a look into the future? Austin Harris.

March 25th Severe Weather Event: Highlighting the difficulties we face as meteorology, and a

look into the future?

Austin Harris

Outline

• Background: the severe weather (or the lack there of) preceding the event

• The forecast: what were the threats and how were they communicated?

• A timeline of the event: a look from the eyes of the forecaster AND the public

• Discussion: What could have been done? And what should be done in the future?

“We are in unchartered territory with respect to lack of severe weather. This has never happened in the record of SPC watches dating back to 1970.” – G Carbin

So far this year: 4 tornado watches;0 T-storm watches

Normal- 52 tornado watches issued by this date each year

IN SUMMARY: Severe weather has been isolated the last two years, and this is continuing into 2015

There is no one clear reason to explain the lack of tornadoes. We're in a persistent pattern that suppresses severe weather, and the right ingredients -- moisture, instability, and lift -- have not been brought together in any consistent way so far this year.” – G Carbin

Meridonal Wind Anomalies (1/1/15-3/2415)

500 mb 700 mb

850 mb 925 mb

Geopotential Height Anomalies (1/1/15-3/2415)

Hypothesis: Persistent western ridge and eastern trough aka “polar vortex” places tornado alley in anomalous northerly flow and in a region of anomalous decent

Any other thoughts?

500 mb 700 mb

850 mb 925 mb

Meridonal wind (left): anomalous northerly flow in plains between 2013-2015

500 mb geopotential height (right): the polar vortex!!!

2013-2015 Averages

This seems to be a trend dating back nearly 3 years- a climatological shift?

…SUMMARY…SEVERE STORMS CAPABLE MAINLY OF LARGE HAIL AND DAMAGING WINDS ARE EXPECTED…

…ATMOSPHERE WILL BE MORE THAN ADEQUATE FOR STRONG SUPERCELLS WITH VERY LARGE HAIL AND LOCALLY DAMAGING WIND….

..THESE STORMS COULD YIELD A COUPLE TORNADOES IN ADDITION TO VERY LARGE HAIL AND DMGG WIND

Even the smartest of people are tough to forecast for

Screen shots of mine

Timeline of the event

4:30 Tell friend to put car in garage5:22 Tornado Warning issued W of Sand Springs, OK5:34 Tornado hits mobile home park in Sand Springs, killing one person5:43 Call intelligent friend just south of downtown Tulsa, he’s asleep. Come on, man!

Although storms developed east of OKC, storms were expected to develop along a cold front

As the storms developed, the NWS and local hero Gary England began spreading the word, emphasizing the low tor risks.

The Timeline

• 6:30 City Leaders in Moore claim to have sounded sirens

• 6:32 NWS issues Sv T-storm for OKC/Moore• 6:35 Estimated time tornado touches down• 6:36 NWS tweets that there is no tornado, but

straight line winds instead• 6:38 NWS tweets that there IS A TORNADO• 6:41 Tornado warning issued for OKC• 6:43 Tornado warning issued for Moore

Local Media Response

KFOR- “MOORE, Okla. – Several residents in Moore say they had only seconds to take cover before their homes were hit by a tornado on Wednesday evening”

“However, many residents say sirens in the area were not going off and a tornado warning was not issued for several minutes”

Several residents didn’t make it to their storm shelter, and were busy watching from the “safety” of their porches, vehicles, and overpasses….. DOH!

NWS Norman Response

Storm Reports v SPC Day 1

Moore tornado: negative lead time, although no deaths occurred.

Sand Springs tornado: appx 15 minutes lead time

No tornado watches issued- 11 tornadoes occurred on this date.

BUST OR NO?

The Questions

• What could have been done?• Is the SPC Day 1 outlook good enough?• Can we blame the NWS?• Should we always be reminding the audience

that anything can happen… so prepare for the worst?

• Can the NWS survive without the media?

The Questions

• Should we all be sending out the same information?

• Which way is best? Probabilistic v deterministic

• Will these changes make a difference?

Questions

• Are tornado sirens the way to go?

• Did the clarification by NWS / media make things worse?

• County based warnings, yay / nay?

• Should emergency managers sound the alarm or should METs?

The Questions

• Accuweather’s 15 minute lead time…. Are they full of crap?

• What are the roles of the private / public sector… can Accuweather replace the NWS?

In Summary: In MY opinion

• This was a complex event that was difficult to warn for• Working together is a must; need to limit conflicting

messages• Improving communication should be the front line of severe

weather forecasting, and it is unclear as to which approach we should take– Phones as the PRIMARY way of disseminating warnings, sirens as a

SECONDARY method– Communicating the uncertainty in forecasts is also needed (whether

or not this can be done with probabilistic charts, I don’t know)– Severe weather education: more emphasis should be placed on Do’s

and Don’ts