SPC AC 160044
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0744 PM CDT SUN MAR 15 2009
VALID 160100Z - 161200Z
...NO SVR TSTM AREAS FORECAST...
...GULF COAST STATES...
POSITIVELY-TILTED MIDLEVEL TROUGH EXTENDING FROM VORTICITY MAXIMUM
OVER THE LOWER MO VALLEY SSWWD INTO THE SRN PLAINS WILL TRANSLATE
EWD INTO THE MIDDLE AND LOWER MS VALLEYS TONIGHT. DCVA ASSOCIATED
WITH THIS FEATURE COUPLED WITH BROAD ISENTROPIC ASCENT IN THE LOW
LEVELS WILL LIKELY MAINTAIN ISOLATED/SCATTERED TSTMS EMBEDDED IN A
LARGER CONVECTIVE PRECIPITATION SHIELD. 00Z REGIONAL SOUNDINGS
INDICATE VERY WEAK LAPSE RATES WHICH WILL LIMIT THE DEGREE OF
CONVECTIVE INSTABILITY AND THE POTENTIAL FOR ANY SEVERE WEATHER.
...WA/ID PNHDL...
00Z UIL/OTX SOUNDINGS SHOWED THE PRESENCE OF RATHER STEEP LAPSE
RATES OWING LARGELY TO COLD MIDLEVEL TEMPERATURES /-28 TO -35 C AT
500 MB/ ASSOCIATED WITH STRONG VORTICITY MAXIMUM AND ATTENDANT JET
STREAKS MOVING EWD ACROSS THE REGION. WHILE AIR MASS REMAINS RATHER
DRY /PW VALUES BELOW .4 INCH/...THESE LAPSE RATES WHERE RESULTING IN
MUCAPE OF 300-400 J/KG. MOREOVER...ACCOMPANYING WIND PROFILES
EXHIBITED QUITE STRONG VERTICAL SHEAR.
VISIBLE SATELLITE AND LIGHTNING DATA INDICATE THAT ISOLATED TSTMS
HAVE ATTEMPTED TO BECOME SUSTAINED OVER THE COLUMBIA BASIN OF ERN WA
INVOF OF SURFACE FRONT. THIS AREA APPEARS TO BE CORRELATED WITH THE
ZONE OF STRONGEST DCVA ASSOCIATED WITH ABOVE-MENTIONED SHORT WAVE
TROUGH. ISOLATED TSTMS WILL REMAIN POSSIBLE FOR THE NEXT FEW HOURS
EWD ACROSS THE ID PNHDL. GIVEN THE ANTICIPATED ISOLATED COVERAGE
AND SHORT DURATION...NO GENERAL THUNDER AREA WILL BE INCLUDED.
..MEAD.. 03/16/2009
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0600Z
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