Thursday, April 3, 2014

Severe Weather Today & Tonight

The threat exists for severe weather in parts of the Midwest today through tonight.  The brunt of this post is going to be for southeast Missouri, southern Illinois and western Kentucky.

The Storm Prediction Center has already issued a Tornado Watch for parts of southeast Missouri, southern Illinois and western Kentucky.  The watch is in effect until 7pm CT Thursday.


Looking over morning computer model data, it appears there will be a decent amount of divergence in the atmospheric column over southeast Missouri, western Kentucky, northwest Tennessee and northeast Arkansas, especially in extreme northeast Arkansas and the Missouri bootheel.  What this basically means is that there will be a lifting mechanism in the atmosphere.  Lifting air allows for thunderstorm development, amongst other things.

Data also suggests instability will be in place over the area through late tonight (10pm-12am).

As of 1pm CT, there is ample "fuel" in the air over southeast Missouri, southern Illinois and western Kentucky.  The area is located in the "warm sector" of the storm.  Dew points have already climbed in to the 60°s.  The moisture, indicated by dew point temperature, acts as the gasoline for the storms.

All we need now is a trigger.  Oh wait, there is a trigger.  An area of low pressure is currently located over eastern Kansas and western Missouri.  This will move to the east and bring a cold front through the area overnight.

So here is my thinking as of now...

There could be two rounds of storms in southeast Missouri, southern Illinois and western Kentucky.

First round is this afternoon where scattered thunderstorms will be possible.  These storms will have the potential to drop large hail, tornadoes and gusty wind.

Second round comes through later tonight as a squall line develops over southwestern Missouri and western Arkansas.  The storms contained within the line will have the potential to produce damaging winds, hail and a couple of tornadoes.

Right now, I think the biggest threat for tornadoes will come during the first round this afternoon through early evening.  Any discreet cells that develop will need to be watched closely.  I'm not saying there couldn't be a tornado later tonight, but I think the better chance will be with the first round.

I used to play a little game where I would pick my target location for storm chasing.  If I were chasing today, my initial target would be Piggot, Arkansas.  Keep in mind, part of choosing a location is for the ability to re-position myself if things change.  Strategically, Piggot would be my spot.

FREAK-OUT-METER:

  • Southern Illinois: 6
  • Western Kentucky: 6
  • Southeast Missouri: 6
  • Missouri Bootheel: 7
Be sure to have a way of receiving severe weather alerts this afternoon/tonight.  If you have a NOAA weather radio, be sure the batteries work and the unit is turned on.

Do NOT rely on warnings from Facebook.  I've discussed this before, but due to Facebook algorithms only 3%-7% of status updates are available for viewing in news feeds.

Twitter is an ok option.  Be sure to follow me at @johndissauer where I send out watch and warning information along with other bits of information on a more real-time basis.