SWODY1
SPC AC 221634
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1134 AM CDT THU MAY 22 2008
VALID 221630Z - 231200Z
...THERE IS A MDT RISK OF SVR TSTMS ACROSS PORTIONS OF NERN
CO...EXTREME SWRN NEB...WRN AND CENTRAL KS...EXTREME NORTHWEST OK...
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE CENTRAL
AND SRN PLAINS...
...SYNOPSIS...
AT MID MORNING...SURFACE LOW WAS LOCATED NEAR COS AND IS FORECAST TO
LIFT SLOWLY ENEWD INTO EAST CENTRAL CO THIS AFTERNOON. DRYLINE
EXTENDED SWD FROM THE LOW TO NEAR THE TX/NM BORDER. WARM FRONT
STRETCHED FROM BETWEEN COS/DEN EWD THROUGH NERN CO AND THEN SEWD
INTO CENTRAL KS. APPARENT FEATURE FOR SURFACE BASED CONVECTION THIS
AFTERNOON AND EVENING WAS A SHORTWAVE TROUGH EVIDENT IN WATER VAPOR
IMAGERY LOCATED NEAR ABQ. THIS SYSTEM SHOULD TURN MORE NWD THROUGH
TIME AS IT ROUNDS THE BASE OF THE UPPER TROUGH...AND GIVEN ITS
CURRENT MOTION NEAR 40 KT...TROUGH SHOULD BE LOCATED IN SERN CO BY
21Z AND THEN CONTINUE NEWD INTO CENTRAL NEB BY 06Z.
...NERN CO/SERN WY/NEB PANHANDLE...
MORNING ANALYSIS SHOWED AN AXIS OF 55 TO 60 DEWPOINTS EXTENDING NWWD
INTO NERN CO ALONG AND NORTH OF WARM FRONT. THE FRONT WILL LIFT ONLY
SLIGHTLY NWD TODAY AND MAINTAIN ESELY BOUNDARY LAYER WINDS. THIS
WILL MAINTAIN 50-60 DEGREE DEWPOINTS THROUGH THE
AFTERNOON...YIELDING SBCAPES BETWEEN 1500-2500 J/KG. SKIES WERE
GENERALLY SUNNY ACROSS MUCH OF THE ERN CO PLAINS...SOUTH OF A
GLY-GLD LINE. MORNING SOUNDING AT DEN WAS WEAKLY CAPPED AND GIVEN
THAT LARGE SCALE ASCENT WILL ARRIVE BY EARLY/MID AFTERNOON...
SURFACE BASED STORMS ARE LIKELY TO DEVELOP ACROSS NERN CO...
ESPECIALLY ALONG AND NORTH OF THE PALMER RIDGE BY EARLY AFTERNOON.
ONCE STORMS FORM...THE AMOUNT OF INSTABILITY AND EFFECTIVE SHEAR AT
60 KT WILL RESULT IN RAPID SUPERCELL DEVELOPMENT. THERMODYNAMIC
PROFILES SUGGEST VERY LARGE HAIL WILL BE THE MAIN THREAT...THOUGH
SRH VALUES FROM 200-300 M2/S2 FAVOR TORNADOES...SOME STRONG. CLOUDS
ARE EXPECTED TO SLOWLY ERODE FROM THE SOUTH ACROSS SERN WY AND
PORTIONS OF THE WRN NEB PANHANDLE BY LATE AFTERNOON. CONTINUED
SEVERE THREAT...INCLUDING POSSIBLE TORNADOES...ARE EXPECTED TO
SPREAD INTO THIS REGION BY LATE AFTERNOON...AND PERSIST INTO THE
EVENING HOURS.
...CENTRAL/WRN KS...SWRN NEB.. NWRN OK...
BAND OF WEAK ELEVATED CONVECTION/CLOUDS WAS EVIDENT THIS MORNING
FROM THE TX PANHANDLE NWD ACROSS FAR ERN CO/WRN KS. THE CLOUDS HAVE
RECENTLY BEEN DECREASING ACROSS THE TX PANHANDLE AND THIS TREND IS
EXPECTED ACROSS THE WARM SECTOR THROUGH THE AFTERNOON HOURS.
APPROACHING SHORTWAVE TROUGH SHOULD AID IN PUSHING DRYLINE EWD INTO
SWRN KS AND THROUGH MOST OF THE TX PANHANDLE BY LATE AFTERNOON.
DEWPOINTS ALREADY HAVE CLIMBED INTO THE LOWER AND MID 60S ACROSS
MUCH OF THE WARM SECTOR. MORNING CLOUDS AND STRONG CAPPING INVERSION
SHOULD LIMIT SURFACE BASED CONVECTION UNTIL LATE AFTERNOON.
HOWEVER...THIS WILL ALOW TEMPERATURES TO CLIMB INTO THE
80S...RESULTING IN MLCAPES FROM 2000-3000 J/KG. THIS INSTABILITY
COMBINED WITH A 70-80 KT SLY MID LEVEL JET AND 50-60 KT DEEP LAYER
SHEAR WILL BE VERY FAVORABLE FOR INTENSE SUPERCELLS. STRONGLY
VEERING WINDS PROFILES IN THE LOWER 1 TO 2 KM...RESULTING IN 1KM SRH
AROUND 300 M2/S2...WILL ALSO SUPPORT A FEW SIGNIFICANT TORNADOES
INTO MID EVENING.
...SRN HIGH PLAINS...
STRONGER BUOYANCY...MLCAPES FROM 3500-3500 J/KG...AND CONVERGENCE
ALONG DRYLINE MAY INITIATE STORMS ACROSS THE ERN TX PANHANDLE AND
WRN OK LATE AFTERNOON. HOWEVER...STRONG CAPPING AND MID LEVEL HEIGHT
RISES MAY LIMIT STORM COVERAGE MORE SO THAN ACROSS KS.
HOWEVER...THIS ENVIRONMENT WOULD ALSO BE FAVORABLE FOR LONGER-LIVED
SUPERCELLS TO DEVELOP. ANY SUPERCELL THAT DEVELOPS COULD PRODUCE A
STRONG TORNADO ALONG WITH VERY LARGE HAIL INTO MID EVENING.
...ERN TX/OK EWD ACROSS THE LOWER MS VALLEY...
WEAK UPPER LOW OVER SERN TX WILL CONTINUE TO MOVE SLOWLY NEWD
THROUGH THE AFTERNOON. AIR MASS IS MODERATELY UNSTABLE WITH RICH
MOISTURE IN THE BOUNDARY LAYER. HOWEVER. SHEAR WILL BE RELATIVELY
WEAK. THE AMOUNT OF INSTABILITY LIKELY WILL RESULT IN A FEW STORMS
WITH MARGINALLY SEVERE HAIL/WINDS...BUT WIND SHEAR SHOULD LIMIT
COVERAGE AND DURATION OF SUCH EVENTS.
..IMY/LEVIT.. 05/22/2008
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