[SWODY1] SWODY1

[Severe Weather Outlook Day 1]

ACUS01 KWNS 011241
SWODY1
SPC AC 011240

DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0640 AM CST SAT APR 01 2006

VALID 011300Z - 021200Z

...THERE IS A MDT RISK OF SVR TSTMS OVER MUCH OF WRN OK...SWRN
KS...ERN TX PANHANDLE LATE THIS AFTERNOON AND EARLY TONIGHT...

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE
SRN/CENTRAL PLAINS...

...WIDESPREAD SEVERE THUNDERSTORMS WILL DEVELOP ACROSS A
CONCENTRATED AREA OF THE CENTRAL/SOUTHERN HIGH PLAINS LATER TODAY...


...SRN/CENTRAL PLAINS...
DRY LINE SEVERE PATTERN...MORE TYPICAL LATER IN THE SPRING...WILL
DEVELOP FROM WRN KS INTO PORTIONS OF WRN TX/OK TODAY AND TONIGHT. 
PRESSURE FALLS AHEAD OF LOW AMPLITUDE SHORTWAVE TROUGH...NOW LIFTING
NEWD ACROSS THE SRN ROCKIES...WILL INCREASE SSELY LOW LEVEL FLOW
INTO THE SRN/CENTRAL HIGH PLAINS THROUGH THE AFTERNOON.  AS THIS
OCCURS...BOUNDARY LAYER MOISTURE WILL QUICKLY INCREASE DUE TO BOTH
DOWNWARD MIXING AND ADVECTION UNDER STRONG CAP EVIDENT AT FTW/OUN
THIS MORNING...WITH AXIS OF 50+F SURFACE DEW POINTS EXPECTED INTO
WRN KS AND MID/UPPER 60F DEW POINTS ALONG AND SOUTH OF I-40 BY LATE
THIS AFTERNOON.  MODELS ARE IN AGREEMENT IN MIXING DRY LINE/LEE
TROUGH ALONG AN AXIS EXTENDING FROM NEAR THE KS/CO BORDER SWD INTO
THE CENTRAL TX PANHANDLE BY 21Z...WHICH THEN PROGRESSES EWD INTO WRN
OK/CENTRAL KS THIS EVENING IN WAKE OF DEEPENING LOW CENTER LIFTING
INTO SERN NEB OVERNIGHT.

HEATING AND MOISTENING WITHIN THE BOUNDARY LAYER WILL BE AUGMENTED
BY INCREASING LARGE SCALE ASCENT AND SUPPORT RAPID SEVERE
THUNDERSTORM DEVELOPMENT FROM SWRN KS INTO THE ERN TX
PANHANDLE...MOST LIKELY AROUND 21-22Z. STORMS WILL QUICKLY BECOME
SUPERCELLS WITH EFFECTIVE BULK-SHEAR NEAR 50 KT...0-2 KM SRH FROM
150-200 M2/S2 AND MLCAPE APPROACHING 2000 J/KG.  AS CAP BREAKS AND
STRONGEST ASCENT OVERSPREADS THE REGION...STORMS WILL BECOME
INCREASINGLY WIDESPREAD WITH POTENTIAL FOR VERY LARGE HAIL AND
TORNADOES.  CAPPING WILL LIMIT SWD DEVELOPMENT ALONG DRY LINE INTO
MORE OF WRN TX.  HOWEVER...SHEAR WILL REMAIN SUPPORTIVE OF
SUPERCELLS SHOULD AN ISOLATED STORM OR TWO DEVELOP LATER TODAY. 

TORNADO THREAT WILL LIKELY INCREASE AROUND 00Z AS SUPERCELLS
MATURE...LOW LEVEL RH INCREASES AND LLJ BEGINS TO
DECOUPLE/INTENSIFY.  FORECAST SOUNDINGS...ESPECIALLY INTO RICHER
BOUNDARY LAYER MOISTURE OVER SWRN OK/NWRN TX...WILL BECOME FAVORABLE
FOR SIGNIFICANT TORNADOES LATE TODAY AND EARLY THIS EVENING. 
ACTIVITY WILL LIKELY ORGANIZE INTO AN MCS AS IT LIFTS ENEWD ACROSS
NRN OK/KS THIS EVENING...WITH MORE DISCRETE DEVELOPMENT DIMINISHING
DURING THE MID EVENING SOUTH OF I-40 AS CAPPING INCREASES AND LARGE
SCALE ASCENT LIFTS INTO THE CENTRAL PLAINS.  SEVERE THREAT...MAINLY
IN THE FORM OF LARGE HAIL AND ISOLATED DAMAGING WINDS...SHOULD
SPREAD INTO PORTIONS OF SRN NEB AND ERN KS/WRN MO LATER TONIGHT.

...SERN OK INTO THE LOWER MS RIVER VALLEY...
MODELS INDICATE CAP WILL REMAIN WEAK ALONG STALLED SURFACE FRONT NOW
EXTENDING ROUGHLY E-W ACROSS THIS REGION.  DEEP LAYER SHEAR IS
FORECAST TO REMAIN MODEST...20-30 KT OF 0-6 KM SHEAR...WITH WEAK
LAPSE RATES EVIDENT ON MORNING SOUNDINGS.  THUS...DESPITE MODERATE
INSTABILITY...SEVERE THREAT WILL LIKELY REMAIN LIMITED TODAY THOUGH
AN ISOLATED LARGE HAIL/DAMAGING WIND SHOULD ACCOMPANY STRONGER
CELLS.

...NEW ENGLAND ACROSS THE CHESAPEAKE REGION...
BROAD AREA OF 50+ SURFACE DEW POINTS AND RATHER WARM SURFACE
TEMPERATURES WILL SUPPORT MARGINAL INSTABILITY AHEAD OF SURFACE COLD
FRONT MOVING ACROSS WRN NY/PA AT 12Z.  THIS FRONT WILL CONTINUE EWD
OFF THE COAST BY LATER TODAY.  CONVECTION HAS ALREADY INCREASED NEAR
THE FRONT INTO CENTRAL NY EARLY THIS MORNING /REFERENCE SWOMCD 387
FOR FURTHER DETAILS/.  DIURNAL HEATING AND 30-40 KT WSWLY FLOW JUST
OFF THE SURFACE SHOULD SUPPORT STRONG TO ISOLATED SEVERE WIND GUSTS
WITH THUNDERSTORMS DEVELOPING ALONG AND AHEAD OF THE FRONT FROM
PORTIONS OF NEW ENGLAND ACROSS MUCH OF THE MID ATLANTIC/CHESAPEAKE.

..EVANS/CROSBIE.. 04/01/2006