Wednesday, March 28th
Hello all, A nice morning will likely turn a bit stormy later today for some – not all. An upper level disturbance is passing well to our north across southern Canada. There is an associated cold front extending south across Indiana which will continue to track southeast across the region today and during the time of maximum heating. Here’s the NAM’s instability field valid 2pm this afternoon. Notice the best instability from about the Ohio River and points south.
Here’s the latest VIS satellite (nid morning Wednesday). Notice the band of clouds north. Even a some “bumpy” appearences showing up along the band of clouds. This is showing embedded towering cumulus.
As the this band of moisture (the front) continues to work south this afternoon, it will be working into an increasingly unstable atmosphere. As a result, thunderstorms should increase along the front this afternoon. It appears the best chances for storm initiation should occur very close to – or just south of the Ohio River during the mid afternoon hours of today. The storms will then settle south and likely be south of our region by evening.
There will be the potential for a few strong/severe cells along the line. Looking at the wind fields would support some of the stronger cells having the potential to create hail and strong, straight lined wind gusts. The tornado potential with this system looks extremely low.
Here’s SPC’s severe discussion:
DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0731 AM CDT WED MAR 28 2012 VALID 281300Z – 291200Z …THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID ATLANTIC REGION INTO CENTRAL KY… …THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF KS/MO/OK/AR… …MID ATLANTIC INTO OH VALLEY… WATER VAPOR IMAGERY SHOWS A LOW AMPLITUDE SHORTWAVE TROUGH MOVING ACROSS THE GREAT LAKES REGION. THE ASSOCIATED SURFACE COLD FRONT CURRENTLY EXTENDS FROM NY/PA INTO SOUTHERN IND. EARLY VISIBLE SATELLITE IMAGERY SHOWS THAT AMPLE SUNSHINE WILL OCCUR AHEAD OF THE FRONT ACROSS THE OH VALLEY AND MID ATLANTIC STATES. MEANWHILE… STRONG SOUTHWESTERLY LOW LEVEL WINDS WILL HELP TO TRANSPORT 50S DEWPOINTS OVER THE TN VALLEY INTO THE MID ATLANTIC REGION. THE END RESULT WILL BE AN AXIS OF MODERATE AFTERNOON INSTABILITY EXTENDING FROM CENTRAL PA/VA INTO TN/KY. MOST MODEL SOLUTIONS SUGGEST THAT SCATTERED SHOWERS AND THUNDERSTORMS CURRENTLY OCCURRING OVER NY/PA WILL BUILD SOUTHWESTWARD WITH TIME AND INTENSIFY LATER TODAY. STEEP LOW LEVEL LAPSE RATES…SUFFICIENT CAPE…AND RATHER STRONG LOW/MID LEVEL WINDS WILL PROMOTE A FEW ORGANIZED STORMS CAPABLE OF LARGE HAIL AND DAMAGING WINDS. THE STORMS SHOULD BEGIN TO DIMINISH SOON AFTER SUNSET.