SPC AC 281200
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0700 AM CDT WED MAY 28 2008
VALID 281300Z - 291200Z
...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF EASTERN NM...
...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF NORTHEAST
CO...SOUTHEAST WY...AND THE NEB PANHANDLE...
UPPER RIDGE IS FORECAST TO STRENGTHEN TODAY OVER THE SOUTHERN
PLAINS...WHILE UPPER TROUGH IS MAINTAINED OFF THE SOUTHERN CA COAST.
A RELATIVELY QUIET DAY /FOR LATE MAY/ IS ANTICIPATED REGARDING
SEVERE WEATHER THREATS ACROSS THE NATION.
...EASTERN NM...
SELY LOW LEVEL WINDS ARE EXPECTED TO CONTINUE THROUGH THE PERIOD
OVER EASTERN NM...WITH DEWPOINTS IN THE 50S TO LOWER 60S INTO THE
FOOTHILLS. STRONG DAYTIME HEATING AND RELATIVELY STEEP LAPSE RATES
WILL YIELD AFTERNOON MLCAPE VALUES OF 500-1000 J/KG AND THE
POTENTIAL FOR SCATTERED THUNDERSTORM DEVELOPMENT. DEEP LAYER
VERTICAL SHEAR WILL BE MARGINAL FOR AN ORGANIZED SEVERE THREAT.
HOWEVER...SUFFICIENT LOW LEVEL SHEAR WILL BE PRESENT THIS EVENING
FOR A FEW STRONG/SEVERE CELLS CAPABLE OF HAIL AND LOCALLY DAMAGING
WINDS.
...NORTHEAST CO/SOUTHEAST WY/NEB PANHANDLE...
BAND OF STRONG SOUTHWESTERLY MID LEVEL WINDS WILL STRETCH ACROSS THE
CENTRAL ROCKIES AND INTO THE ADJACENT HIGH PLAINS TODAY.
SOUTHEASTERLY LOW LEVEL WINDS WILL DRAW MOIST AIRMASS BACK TOWARD
REGION...BUT DEWPOINTS WILL LIKELY REMAIN IN THE 40S OVER EASTERN
CO/WY THROUGH THE EVENING. NEVERTHELESS...STEEP LAPSE RATES AND
FULL SUNSHINE WILL LIKELY RESULT IN AFTERNOON MLCAPE VALUES AROUND
500 J/KG. SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
PROPAGATE OFF THE HIGHER TERRAIN OVER NORTHEAST CO/SOUTHEAST WY
LATER TODAY. STRONG DEEP LAYER VERTICAL SHEAR WILL POSE A THREAT OF
A FEW SEVERE CELLS CAPABLE OF HAIL AND DAMAGING WINDS. STORMS WILL
LIKELY WEAKEN AS THEY SPREAD EASTWARD AND AWAY FROM THE MOUNTAINS
WHERE A STRONG CAPPING INVERSION WILL BE PRESENT.
FARTHER TO THE NW OVER THE NRN ROCKIES...DIURNAL TSTMS ARE EXPECTED
TO BE MORE NUMEROUS IN ADVANCE OF SHORT WAVE TROUGH LIFTING NWD
THROUGH THE REGION. WHILE LOW-LEVEL MOISTURE AND VERTICAL SHEAR
WILL REMAIN SOMEWHAT MARGINAL...THE PRESENCE OF STEEP LAPSE RATES
AND RESULTANT WEAK CONVECTIVE INSTABILITY MAY SUPPORT A FEW STRONGER
STORMS CAPABLE OF GUSTY WINDS AND SOME HAIL.
...MID MO VALLEY...
NOCTURNAL LLJ IS FORECAST TO STRENGTHEN OVER THE CNTRL AND SRN
PLAINS TONIGHT...ENHANCING LOW-LEVEL MOISTURE AND WARM THERMAL
ADVECTIONS ACROSS THE REGION. THESE PROCESSES WILL OCCUR BENEATH
STEEP MIDLEVEL LAPSE RATES WITH MUCAPES INCREASING TO 1000-1500
J/KG. ELEVATED TSTMS ARE EXPECTED TO DEVELOP TONIGHT WITHIN THE WAA
REGIME...A FEW OF WHICH WILL BE CAPABLE OF LARGE HAIL GIVEN THE
MODERATE INSTABILITY AND MODERATELY STRONG CLOUD-BEARING SHEAR.
...GULF COAST STATES...
LOW-LEVEL AIR MASS WILL BE QUITE MOIST TODAY AHEAD OF SYNOPTIC FRONT
AND ANY RESIDUAL OUTFLOW BOUNDARIES WITH DEWPOINTS IN THE
60S...CONTRIBUTING TO MLCAPES OF 1000-2000 J/KG. VERTICAL SHEAR AND
MIDLEVEL LAPSE RATES WILL REMAIN WEAK...BUT THE MODERATE INSTABILITY
MAY PROMOTE A FEW STRONGER STORMS CAPABLE OF LOCALLY DAMAGING WET
MICROBURSTS AND PERHAPS SOME HAIL.
..HART/JEWELL.. 05/28/2008
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z
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