SPC AC 300543
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1243 AM CDT SUN MAY 30 2010
VALID 301200Z - 311200Z
...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS KS/OK AND TX
PANHANDLE...
...SYNOPSIS...
UPPER AIR PATTERN OVER CONUS FCST TO DEAMPLIFY SOMEWHAT THROUGH
REMAINDER PERIOD AS CYCLONE ALOFT -- NOW EVIDENT IN MOISTURE CHANNEL
IMAGERY OVER SRN AB -- MOVES NEWD ACROSS SK. ACCOMPANYING SHORTWAVE
TROUGH -- INITIALLY OVER ERN MT...CENTRAL WY AND NERN UT -- IS
EXPECTED TO LIFT NEWD ACROSS DAKOTAS AND WRN/NRN MN TODAY WHILE
DEAMPLIFYING. MEANWHILE...BROAD...WEAK AND INITIALLY
QUASISTATIONARY UPPER CYCLONE OVER MS IS FCST TO DRIFT NEWD ACROSS
NRN AL.
AT SFC...CYCLONE ANALYZED OVER NWRN MN IS EXPECTED TO MOVE ENEWD
ACROSS NERN ONT AND OCCLUDE...WHILE SECONDARY CYCLONE DEVELOPS ALONG
OCCLUSION TRIPLE POINT OVER LS BY 31/00Z. TRAILING COLD FRONT WILL
MOVE TO NEAR NRN WI...NWRN MO...S-CENTRAL KS...NWRN OK AND S-CENTRAL
TX PANHANDLE BY LATE AFTERNOON. FRONT SHOULD REACH LM...NRN/WRN
IL...W-CENTRAL MO...CENTRAL OK AND SERN NM BY END OF PERIOD.
...CENTRAL/SRN PLAINS...
COMBINATION OF FRONTAL CONVERGENCE AND STG DIABATIC HEATING SHOULD
SUFFICE TO REMOVE CAP BY MID-LATE AFTERNOON...LEADING TO
BANDS/CLUSTERS OF SCATTERED-NUMEROUS TSTMS. WHILE DEEP-LAYER WINDS
AND SHEAR ARE NOT EXPECTED TO BE STG...LARGE BUOYANCY AND POTENTIAL
FOR CONCENTRATION OF CONVECTION THROUGH UPSCALE GROWTH WILL
CONTRIBUTE TO RELATIVELY MAXIMIZED POTENTIAL FOR SVR...COMPARED TO
ELSEWHERE INVOF FRONTAL ZONE. STEEP LOW-LEVEL LAPSE RATES IN
WELL-MIXED BOUNDARY LAYER...BENEATH MLCAPE 2000-3500 J/KG...WILL
CONTRIBUTE TO POTENTIAL FOR DAMAGING GUSTS AND SVR HAIL.
SLOW-MOVING MCS MAY DEVELOP OVER PORTIONS CATEGORICAL SLGT RISK AREA
DURING EVENING HOURS AND SHIFT EWD TO SEWD ACROSS OK WITH MIXTURE OF
FORWARD- AND REARWARD-PROPAGATIONAL CONTRIBUTIONS TO MOTION.
HIGH-BASED TSTMS WITH STG-SVR GUSTS AND HAIL ALSO ARE POSSIBLE
FARTHER W ACROSS SRN HIGH PLAINS.
...UPPER MS VALLEY TO LS AREA...
PREFRONTAL CORRIDOR OF ENHANCED BOUNDARY LAYER MOISTURE...WITH SOME
EVAPOTRANSPIRATIVE ENHANCEMENT...SHOULD ACT TOGETHER WITH FRONTAL
FORCING AND STG SFC HEATING TO YIELD POTENTIAL FOR TSTMS THIS
AFTERNOON. THIS ACTIVITY SHOULD MOVE EWD TO NEWD ACROSS REGION WITH
OCCASIONAL HAIL/GUSTS NEAR SVR LEVELS POSSIBLE. FCST WIND PROFILES
GENERALLY ARE UNIDIRECTIONAL THROUGH TROPOSPHERE...WITH WELL-MIXED
BOUNDARY LAYER AND 1000-1500 J/KG MLCAPE. LACK OF MORE ROBUST
DEEP-LAYER SHEAR WILL PRECLUDE WELL-ORGANIZED SVR THREAT.
...SERN CONUS...
CLUSTERS AND BANDS OF TSTMS ARE FCST TO DEVELOP AGAIN TODAY OVER
BROAD AREA OF SERN CONUS...BENEATH CYCLONIC GYRE...INVOF FL SEA
BREEZE FRONTS...AND NEAR RESIDUAL FRONTAL ZONE OVER PORTIONS
TIDEWATER REGION INLAND/WWD OVER PIEDMONT. ACTIVITY WILL BE
SUPPORTED BY RICH LOW-LEVEL MOISTURE AND WEAK MLCINH AMIDST POCKETS
OF STG DIURNAL SFC HEATING. WEAK DEEP-LAYER WINDS AND LACK OF MORE
ROBUST SHEAR WILL KEEP ORGANIZATION OF TSTMS MULTICELLULAR IN
NATURE. MESOBETA- AND SMALLER-SCALE FOCI WILL DETERMINE ANY MORE
CONCENTRATED SVR AREAS WITHIN BROADER/MRGL PROBABILITIES OUTLOOKED
ATTM.
..EDWARDS/STOPPKOTTE.. 05/30/2010
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z
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