Monday, April 8, 2013

April 9th Severe Weather Outbreak

Have demoted post title as a result of no upgrade to 'Moderate Risk' of severe weather by Storm Prediction Center.

Predicted Exclusive Risk Index (ERI) for April 9th, 2013
Discussion: After a quick vacation day, I am back to analyze the threat for this severe weather event on April 9th.

High resolution model guidance is concerning and unsupportive of widespread tornado development. Current solution appears to be isolated thunderstorm development quickly congealing into a squall line. My thinking is these cells are only briefly able to mature into supercells before coming together, greatly constricting tornado development. Storm Prediction Center continues to hint at the potential for an upgrade to a Moderate Risk for an undetermined area, but with that upgrade not coming today, the chances for the earlier-predicted tornado outbreak have lowered.

Have pulled out the blue 'Severe' risk area from the ERI to reflect lowering chances for a big severe weather event, but maintained a solid area of 'Enhanced' severe weather. I placed this Enhanced area from Oklahoma and southeast Kansas into Missouri and northwest Arkansas. The angle of this risk area was made to coincide with expected northeast storm motions , but may have to be expanded a bit north into Kansas if later model forecasts take the storm into a more north-northeast motion.

Will update as needed tomorrow afternoon, but here's a few notes on the situation:

•Storm Action Day will be formally declared tomorrow.
•Storm Action Day will LIKELY be declared on April 10th.
•Critical Storm Action Day is UNLIKELY on April 9th and 10th.

Andrew