SPC AC 031235
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0635 AM CST THU MAR 03 2011
VALID 031300Z - 041200Z
...NO SVR TSTM AREAS FORECAST...
...GREAT BASIN INTO CNTRL HIGH PLAINS...
LOW-AMPLITUDE MIDLEVEL TROUGH CURRENTLY OVER THE ERN PACIFIC INTO
GREAT BASIN WILL TRANSLATE THROUGH THE INTERMOUNTAIN WEST WITH
NOTABLE MIDLEVEL COOLING AND RESULTANT STEEPENING OF LAPSE RATES
FORECAST ALONG CYCLONIC SIDE OF ASSOCIATED UPPER-LEVEL JET STREAK.
12Z REGIONAL SOUNDINGS INDICATE THAT AMBIENT ENVIRONMENT IS RATHER
DRY WITH PW VALUES OF LESS THAN A HALF INCH. HOWEVER...THE PRESENCE
OF STEEP MIDLEVEL LAPSE RATES /7.5-8.5 C PER KM/ COUPLED WITH
FORCING FOR ASCENT AHEAD OF MIDLEVEL TROUGH WILL SUPPORT AN INCREASE
IN TSTM ACTIVITY THROUGH THE DIURNAL HEATING CYCLE. GREATEST TSTM
COVERAGE WILL OCCUR ALONG THE HIGHER TERRAIN OF UT/CO WITH MORE
ISOLATED DEVELOPMENT AS FAR E AS VICINITY OF LEE TROUGH AND COLD
FRONT OVER THE HIGH PLAINS.
...LOWER MS VALLEY INTO UPPER GREAT LAKES...
LOW-LEVEL MASS RESPONSE TO APPROACHING MIDLEVEL TROUGH WILL ENHANCE
THE NWD FLUX OF AN INCREASING WARM/MOIST AIR MASS THROUGH THE LOWER
MS INTO OH VALLEY. THIS MOISTURE RETURN WILL OCCUR BENEATH AN
ELEVATED MIXED LAYER ADVECTING EWD FROM THE PLAINS...RESULTING IN A
CAPPED BUT WEAKLY UNSTABLE AIR MASS. BROAD ZONE OF ISENTROPIC
ASCENT/WAA DEVELOPING ALONG NOCTURNAL LLJ MAY SUFFICIENTLY ERODE CAP
SUCH THAT A FEW ELEVATED TSTMS WILL BE POSSIBLE GENERALLY AFTER
04/09Z.
..MEAD.. 03/03/2011
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z
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