SPC AC 270515
DAY 2 CONVECTIVE OUTLOOK RESENT 1
NWS STORM PREDICTION CENTER NORMAN OK
1215 AM CDT SUN MAR 27 2011
VALID 281200Z - 291200Z
...NO SVR TSTM AREAS FORECAST...
...SYNOPSIS...
SYNOPTIC UPPER PATTERN WILL CHANGE LITTLE THROUGH MONDAY. BELT OF
PROGRESSIVE WLYS WILL PERSIST ACROSS THE SRN TWO THIRDS OF THE U.S.
BENEATH HIGH LATITUDE OMEGA BLOCK. ANOTHER IN A SERIES OF SHORTWAVE
TROUGHS WILL MOVE INTO THE CNTRL HIGH PLAINS LATER MONDAY NIGHT.
IMPULSE NOW MOVING INTO CNTRL ROCKIES WILL CONTINUE THROUGH THE MID
ATLANTIC REGION DURING THE DAY. STALLED FRONT WILL PERSIST FROM NRN
FL WWD ALONG THE GULF COAST. WRN EXTENSION OF THE FRONT WILL ADVANCE
NWD THROUGH TX AS LEE CYCLONE DEVELOPS OVER THE CNTRL HIGH PLAINS.
DRYLINE WILL BECOME ESTABLISHED OVER WRN OR W-CNTRL TX AS MODIFIED
CP AIR ADVECTS NWWD.
...FL THROUGH THE GULF COAST...
WLY BOUNDARY LAYER FLOW WILL ADVECT UPPER 60S DEWPOINT THROUGH
PRE-FRONTAL WARM SECTOR BY MONDAY. HOWEVER...MODELS CONTINUE TO
SUGGEST THAT CONVECTION THAT DEVELOPS OVER THE GULF COULD SPREAD
INLAND DURING THE MORNING AND LIMIT INSTABILITY. WHERE DIABATIC
WARMING DOES OCCUR MLCAPE COULD APPROACH 1500 J/KG. GIVEN WEAK
CAP...STORMS WILL LIKELY REDEVELOP WHERE THE BOUNDARY LAYER CAN
DESTABILIZE ALONG AND SOUTH OF THE FRONT OR EXISTING OUTFLOW
BOUNDARIES. STRONGER LOW LEVEL FLOW SHOULD REMAIN WELL NORTH OF
FRONT IN ASSOCIATION WITH MID ATLANTIC SHORTWAVE TROUGH...BUT
MODERATE ZONAL FLOW ALOFT WILL MAINTAIN 35-45 KT UNIDIRECTIONAL
SHEAR IN WARM SECTOR. A FEW ORGANIZED STORMS WITH POTENTIAL FOR
MAINLY ISOLATED STRONG WIND GUSTS WILL BE POSSIBLE. EXPECTED
MARGINAL THERMODYNAMIC ENVIRONMENT WILL PROBABLY SERVE AS A LIMITING
FACTOR FOR A MORE ROBUST SEVERE EVENT.
OTHER STORMS MAY FORM FARTHER WWD IN VICINITY OF STALLED BOUNDARY
NEAR THE GULF COAST WHERE MODERATE INSTABILITY AND 30-40 KT VERTICAL
SHEAR COULD SUPPORT A THREAT FOR ISOLATED STRONG WIND GUSTS AND
HAIL.
...N-CNTRL TX...CNTRL AND ERN OK...SERN KS AND NWRN AR...
STRENGTHENING SLY LLJ MONDAY NIGHT WILL RESULT IN NWD
DESTABILIZATION AND SUBSTANTIAL ISENTROPIC LIFT NORTH OF BOUNDARY
ACROSS PARTS OF CNTRL/ERN OK...KS INTO THE LOWER MS VALLEY. THE MOST
LIKELY AREA FOR INITIATION WILL REMAIN NORTH OF GREATER MUCAPE WHERE
CAP SHOULD BE WEAKER ALONG NERN EXTENSION OF EML PLUME. STEEP MID
LEVEL LAPSE RATES AND 500-1000 J/KG MUCAPE WILL SUPPORT A THREAT OF
ISOLATED LARGE HAIL WITH THE STRONGER STORMS. AT THIS TIME...OVERALL
THREAT DOES NOT APPEAR TO WARRANT MORE THAN 5% SEVERE PROBABILITIES.
...WRN THROUGH W-CNTRL TX...
RETURN OF MODIFIED CP AIR BENEATH STEEP LAPSE RATES WILL RESULT IN
1000-1500 J/KG MLCAPE IN MOISTENING WARM SECTOR. DRYLINE SHOULD
BECOME ESTABLISHED OVER WRN TX...POSSIBLY MIXING INTO W-CNTRL TX
MONDAY AFTERNOON. GIVEN MODEST LOW LEVEL MOISTURE RETURN DURING THE
DAY AND CAPPING INVERSION WITH EML PLUME...ONLY VERY ISOLATED
COVERAGE WILL BE POSSIBLE IF STORMS CAN DEVELOP AT ALL WITHIN ZONE
OF MIXING ALONG DRYLINE. CONDITIONAL THREAT FOR A SUPERCELL WITH
ISOLATED LARGE HAIL WILL EXIST DURING THE AFTERNOON. ANY STORM THAT
DEVELOPS WILL RAPIDLY DIMINISH AFTER SUNSET.
..DIAL.. 03/27/2011
CLICK TO GET WUUS02 PTSDY2 PRODUCT
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 1730Z
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