Well, the SPC has placed most of us under a high risk for this afternoon NE of the Little Rock Metro Area. When the SPC puts out a high risk it basically means that it is not going to be a good day weather wise….. It actually will be a very bad day with destructive wind and tornadoes. This is the type of day parts of Arkansas will have starting from around 1pm on throughout the day. Ok, so let’s get into analysis mode because as of this point in time looking at the 2351897150 computer models that are available is pointless. When it comes down to the event timing within 1-2 hours of the start, analysis is the most important thing. The first we take a look at the surface features, this tells us everything in terms of where things are going to begin. Notice the low at the surface low is located in south Kansas this afternoon. The dryline extended down into eastern portions of Oklahoma into western Arkansas. That dryline is where all the afternoon activity will begin.
This next map is the high levels of instability we are looking at, most of central and eastern portions of the state are HIGHLY unstable, basically the atmosphere is a pressure cooker. The problem this
afternoon comes when the very cold aloft comes in and rides over that unstable air. Temps at 18,000 feet are going to cool around 4-8 degrees at 18,000 feet, but surface temps will rise another 5-10 degrees… Not a good scenario for Arkansas today. Our next map is a thing called helicity, yes just like a helix……
Now those numbers are pretty high, but when you get a storm that turns to the right, the helicity increases dramatically….. levels above 200 are the key for tornadic development. We can discuss a theory of mine when it comes to helicity and tornado genesis at another date when we aren’t preparing for some pretty big storms.
You can see here on the visible satellite that storms are already firing up and getting ready to move into central and eastern Arkansas where the instability and helicity is located. The last thing we need is that cold punch of cold air at the upper levels, that is seen here in the water vapor imagery…. With all these things we have a new PDS watch for the state……. Stay Safe!