October 2 OV Severe Weather

[snowlover2]

SPC has introduced a slight risk area for parts of OH/KY.

DAY 2 CONVECTIVE OUTLOOK

NWS STORM PREDICTION CENTER NORMAN OK

1223 AM CDT MON OCT 01 2012

VALID 021200Z - 031200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS THE OH VALLEY...

...OH VALLEY...

EWD PROGRESSION OF LONG WAVE TROUGH ACROSS THE MS VALLEY WILL BE

SLOW INTO THE DAY2 PERIOD...THOUGH SUBSTANTIAL FLOW WILL DEVELOP ON

DOWNSTREAM SIDE OF THIS FEATURE DURING THE LATTER HALF OF THE PERIOD

ENCOURAGING TROUGH DISPLACEMENT INTO THE OH VALLEY BY DAY3.

SHORT-RANGE MODELS SUGGEST A FOCUSED EXIT REGION OF MID LEVEL JET

WILL SPREAD ACROSS THE TN VALLEY INTO THE OH VALLEY TUESDAY

AFTERNOON. THE NAM IS A BIT MORE AGGRESSIVE WITH THIS ZONE OF

ASCENT AND ALLOWS FOR SUBSTANTIAL BOUNDARY LAYER HEATING BY MID DAY

FROM NERN KY INTO CNTRL OH. WHILE THE GFS DOES NOT STEEPEN BOUNDARY

LAYER LAPSE RATES TO THE DEGREE THE NAM DOES THERE IS REASON TO

BELIEVE SIGNIFICANT DESTABILIZATION MAY OCCUR IN CONCERT WITH

STRENGTHENING WIND FIELDS AHEAD OF SFC LOW AS IT MIGRATES ACROSS WRN

KY INTO SRN IND. NAM SUGGESTS LLJ WILL STRENGTHEN ACROSS THIS

REGION DURING THE DAY WHICH ALLOWS LOW LEVEL MOISTURE TO RETURN

NORTH OF THE OH RIVER. BY MID DAY FORECAST SOUNDINGS FOR SRN OH

EXHIBIT SUPERCELL PROFILES WITH SFC-6KM SHEAR ON THE ORDER OF

55-60KT AND SFC-3KM SRH AROUND 200 M2/S2. IF THIS ENVIRONMENT

EVOLVES AS DEPICTED BY LATEST NAM THEN A FEW SUPERCELLS COULD EVOLVE

AS SFC TEMPERATURES WARM THROUGH THE 70S. ISOLATED TORNADOES ALONG

WITH DAMAGING WINDS MAY ACCOMPANY THE MORE ROBUST ACTIVITY. HAVE

OPTED TO INCREASE SEVERE PROBS ACROSS THE OH VALLEY TO ACCOUNT FOR

THIS SCENARIO.

DOWNSTREAM EAST OF THE APPALACHIANS...LARGE SCALE FOCUS WILL REMAIN

WEST OF THE MOUNTAINS AND THOUGH LOW LEVEL WARM ADVECTION SHOULD

DRIVE SCATTERED CONVECTION ACROSS THE CAROLINAS INTO THE MIDDLE

ATLANTIC IT APPEARS ORGANIZED SEVERE THREAT WILL REMAIN LOW THIS

PERIOD.