Wednesday, April 17, 2013

Spring Throws Punch Number 2 Thursday


Here we go again.  I have hesitated to post an update for a number of reasons, but mainly due to some uncertainties.  The picture is becoming more clear today.  Remember, no matter how much data you look at, the weather is going to do what it wants to do.  Sometimes we rely way too much on data instead of just stepping back from the situation and asking ourselves, "what usually happens with a system like this."

Our own Channel 7 Storm Chaser, WeatherNinja, is out in the plains chasing today and you can watch his live stream here.  It will be down at times due to limited  cell coverage.  If things get going around here Thursday, he'll be chasing in Arkansas.

REBROADCAST OF ANY OF THESE LIVE CHASE FEEDS IS STRICTLY FORBIDDEN.


I think this is going to be a line of storms with embedded cells.  Those cells along with anything that forms in front of the main line will have a chance to produce isolated tornadoes.  While that's possible, the threat for damaging winds and hail will be higher.  Here's a look at the exact timing and threats involved.

This is hi res model data showing you simulated radar valid at 10 AM Thursday.  That's a line of strong/sever thunderstorms over western and northwestern Arkansas.  The airmass in front of this over central and eastern Arkansas will have a chance to destabilize throughout the day.  Thick cloud cover will be a good thing as this keeps instability levels in check.  However, I think we'll warm up with breaks in the clouds and that will make the air unstable.
This is 1PM Thursday.  The line of storms is edging into central Arkansas.  At this point, they will begin to intensify as it taps into increasingly unstable air.
This is 4PM in the afternoon and the line is moving through central Arkansas.  I think there will be a few severe thunderstorm warnings at this time and we'll have to watch for anything that spins along that line or any cells that develop ahead of it in the unstable airmass.  Temperatures are plummeting at this point across western and northwestern Arkansas behind the front.
Here's a look at surface temperatures at 4PM according to this one piece of data.  There is no mistaking where the front is located and it's moving into western Pulaski county.  It's 72 in Little Rock, but 55 in Russellville.  Remember, this is just one piece of data and the timing won't be exact, but you get the picture here.
By 7PM, the storms are located on the Mississippi River and the threat for severe weather will be decreasing at this time for much of the Channel 7 viewing area... again, according to this one piece of model data.
The Storm Prediction Center has placed all of Arkansas in a "Slight Risk" for severe weather Thursday.
That risk for all modes of severe weather is highest across the red shaded area.  This is where the atmosphere will have the chance to destabilize and shear will be highest.
IN SUMMARY, YES, THERE WILL LIKELY BE SOME SEVERE WEATHER THURSDAY.  AN OUTBREAK?  AT THIS TIME IT DOESN'T LOOK LIKE AN OUTBREAK OF TORNADOES, BUT WE'LL WATCH THIS CAREFULLY.  LIKE I SAID, YOU CAN LOOK AT THE DATA ALL DAY LONG AND MOTHER NATURE WILL DO WHAT SHE WANTS TO DO.  I THINK THE MAIN THREAT WILL BE HIGH WINDS, THEN HAIL, THEN ISOLATED TORNADOES.

AFTER THE FRONT PASSES, MUCH COLDER AIR MOVES INTO THE STATE AND FRIDAY AND SATURDAY MORNING LOOK CHILLY.  WE'LL HAVE TO WATCH FOR FROST/FREEZING CONDITIONS, ESPECIALLY UP NORTH.  STAY TUNED.

1 comment:

Rhonda said...

Thanks Todd. We appreciate all the good details that you give us. People want to know specifics and you make sure that we have them. I appreciate all your hard work and always staying on top of this crazy Arkansas weather.