SPC has an enormous slight risk area for tomorrow and tomorrow evening, parts of which include northern and central SC (including the northern tier of the Charleston Tri-County area) as a strong Great Lakes system and associated front push eastward (and weaken). WFO Charleston has not been sold on this scenario thus far due to the forecast weakening and unfavorable timing:
STORM PREDICTION CENTER HAS BROUGHT THE NORTHERN THIRD OF THE
FORECAST AREA INTO A DAY 2 SLIGHT RISK. THE FOCUS FOR CONCERN
APPEARS TO BE WITH THE TAIL END OF A CONVECTIVE LINE WEDNESDAY
EVENING AND OVERNIGHT…ENHANCED BY INCREASED FORCING FROM THE COLD
FRONT AS WELL AS A 30 TO 40 KT LOW LEVEL JET DESCENDING INTO THE
WESTERN AND NORTHERN ZONES. INSTABILITY WILL BE WEAK…ESPECIALLY
CONSIDERING THE LESS FAVORABLE NOCTURNAL TIMING OF THIS THREAT.
PREFER TO KEEP MENTION OF SEVERE WEATHER OUT OF THE HAZARDOUS
WEATHER OUTLOOK AT THIS TIME DUE TO UNCERTAINTIES IN THE AVAILABLE
INSTABILITY…COVERAGE OF SHOWERS AND THUNDERSTORMS…AND
POTENTIAL WEAKENING OF THE SYSTEM UPON ITS APPROACH.
I’ll keep an eye on this but it doesn’t appear it will be much to contend with tomorrow night. Rumbles of thunder aren’t out of the question overnight into Thursday.
Saturday may be a more favorable severe weather day:
IT SHOULD BE NOTED THAT LOW LEVEL WIND FIELDS AHEAD OF THE FRONT
APPEAR VERY IMPRESSIVE. IF THE ATMOSPHERE CAN DESTABILIZE ENOUGH
AHEAD OF THE FRONT…THEN THERE IS CERTAINLY A POTENTIAL FOR SEVERE
WEATHER ACROSS THE AREA. IN ADDITION…BREEZY OR WINDY CONDITIONS
ARE EXPECTED ON SATURDAY…EVEN OUTSIDE OF CONVECTION DUE TO THE
STRONG LOW LEVEL WIND FIELDS…AND AGAIN ON SUNDAY WITH STRONG
COLD AIR ADVECTION IN WAKE OF THE FRONT.
There’s a lot of divergence in the model solutions still, especially with the upper-air setup. The GFS wants to do something similar to last Friday in which the area was in the right-rear entrance region of the jet, allowing for divergence aloft; the Euro is digging a deeper trough over Texas and is staying a bit more to the west. Will be a situation to watch as we get into meteorological spring starting Thursday.