[SWODY2] SWODY2

[Severe Weather Outlook - Day 2]

ACUS02 KWNS 120541
SWODY2
SPC AC 120540

DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
1240 AM CDT WED APR 12 2006

VALID 131200Z - 141200Z

...THERE IS A SLGT RISK OF SVR TSTMS FROM SERN MN INTO WRN IND...

...MID-UPPER MS VALLEY/OH VALLEY...

WEAK HEIGHT FALLS WILL SPREAD ACROSS THE NRN PLAINS LATE IN THE
PERIOD AS SHORTWAVE TROUGH FLATTENS UPPER RIDGE AND DIGS SEWD TOWARD
THE UPPER GREAT LAKES REGION.  THIS FEATURE WILL INDUCE SFC
CYCLOGENESIS ALONG PSEUDO WARM FRONT OVER ERN SD...WHICH WILL THEN
TRACK SEWD ACROSS SRN PORTIONS OF LAKE MI INTO NRN OH LATE IN THE
PERIOD.  WARM ADVECTION AND ASCENT AHEAD OF SHORTWAVE WILL BE
CONFINED TO AREAS NORTH OF THIS BOUNDARY...WHILE VEERED BOUNDARY
LAYER FLOW AND WEAK CONVERGENCE WILL DOMINATE THE WARM SECTOR.

LATEST ETA MODEL GUIDANCE APPEARS TOO AGGRESSIVE IN MOISTURE RETURN
WHICH ERRONEOUSLY GENERATES SBCAPE VALUES IN EXCESS OF 3500J/KG
ACROSS PORTIONS OF IA. NO DOUBT STEEP LAPSE RATE ENVIRONMENT AND
STRONGLY SHEARED PROFILES WILL FAVOR POTENTIAL SUPERCELL DEVELOPMENT
WITHIN WARM ADVECTION ZONE...HOWEVER INSTABILITY WILL LIKELY FALL
WITHIN 1000-1500 J/KG RANGE ALONG/NORTH OF FRONTAL BOUNDARY AS WARM
SECTOR MOISTURE SHOULD BE GREATLY REDUCED.  IT APPEARS SLIGHTLY
ELEVATED THUNDERSTORMS WILL EVOLVE JUST NORTH OF BOUNDARY DURING THE
LATE AFTERNOON HOURS WHERE WSWLY LLJ WILL BE FOCUSED OVER SERN
MN/WCNTRL WI.  THIS ACTIVITY...POTENTIALLY SUPERCELLULAR...SHOULD
SPREAD SEWD ACROSS SRN WI/NRN IL INTO WRN IND DURING THE EVENING
HOURS. FORECAST SOUNDINGS SUGGEST THERE IS SOME POTENTIAL FOR WARM
SECTOR DEVELOPMENT AROUND 00Z WITHIN AXIS OF STRONGEST HEAT FROM ERN
IA INTO NRN MO.  GIVEN WEAK CONVERGENCE ANY CONVECTION THAT EVOLVES
WITHIN THIS ZONE SHOULD BE SHORT LIVED AND DISSIPATE AFTER DARK. 
MORE CONCENTRATED ACTIVITY WILL SPREAD/DEVELOP SEWD INTO PORTIONS OF
THE OH VALLEY WHERE ASCENT SHOULD AID CONVECTION WELL INTO THE
OVERNIGHT HOURS.  AT THIS TIME HAIL APPEARS TO BE THE PRIMARY
CONCERN...ESPECIALLY IF PARCELS ARE FORCED TO CONVECT NORTH OF
FRONTAL ZONE.

..DARROW.. 04/12/2006