SWODY1
SPC AC 030059
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0759 PM CDT WED SEP 02 2009
VALID 030100Z - 031200Z
...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS CENTRAL NEB....
...SYNOPSIS...
PATTERN ALOFT FEATURES MEAN TROUGHING OVER ERN CONUS AND RIDGING IN
W. NERN PACIFIC MID-UPPER CYCLONE -- ITS CENTER NOW EVIDENT IN
MOISTURE CHANNEL IMAGERY INVOF 45N134W -- IS EXPECTED TO DEAMPLIFY
SLIGHTLY AND BECOME STG/OPEN-WAVE TROUGH...MOVING ONSHORE WA/ORE
COAST AROUND 12Z. COMPACT MID-UPPER LOW OVER SERN SD IS FCST TO
MOVE SSEWD ACROSS ERN NEB THROUGH REMAINDER PERIOD. ANOTHER
MID-UPPER CYCLONE OF SIMILAR SIZE/INTENSITY OVER SWRN IL IS EXPECTED
TO MOVE SEWD ACROSS WRN KY OVERNIGHT. FARTHER SE...BROAD/DIFFUSE
SHORTWAVE TROUGH -- NOW EXTENDING FROM CENTRAL GULF OF MEXICO NEWD
ACROSS GA -- SHOULD MOVE SLOWLY EWD.
AT SFC AT 23Z...DIFFUSE COLD FRONT WAS ANALYZED FROM SERN SD LOW
NWWD THROUGH WEAKER LOW OVER NWRN SD...THEN NWD ACROSS WRN ND. THIS
FRONT SHOULD MOVE WWD AND SWWD ACROSS MUCH OF SRN/WRN SD AND
REMAINDER ND. MEANWHILE...WARM FRONT -- DRAWN FROM LOW SWWD ACROSS
CENTRAL NEB TO CENTRAL CO -- SHOULD MOVE SLOWLY SEWD AND BECOME MORE
ILL-DEFINED IN THERMAL FIELD AFTER NIGHTFALL...GIVEN DRIER AIR MASS
AT HIGHER ALTITUDE ON ITS W SIDE. SEPARATE WARM FRONT -- ALSO
DEMARCATING WARMER AND MORE WELL-MIXED AIR TO ITS W -- WAS ANALYZED
FROM SWRN KS SEWD ACROSS WRN OK TO PORTIONS NW/N-CENTRAL TX. WRN
SEGMENT OF THIS FRONT -- FROM NW OK NWWD...MAY RETURN SWD OVERNIGHT
IN RESPONSE TO WEAK SFC CYCLOGENESIS INVOF SWRN OK.
...PORTIONS NRN/CENTRAL PLAINS...
LOW LEVEL LIFT ALONG/AHEAD OF WARM FRONT...JUXTAPOSED WITH
RELATIVELY MOIST/SFC-BASED EFFECTIVE INFLOW PARCELS AND STG
DIRECTIONAL SHEAR...IS CONTRIBUTING TO FAVORABLE ENVIRONMENT FOR
STG-SVR TSTMS ACROSS PORTIONS SD/NEB. STORM MODE OVER NEB MAY
REMAIN INTERMITTENTLY SUPERCELLULAR...WHILE LINEAR AND WEAKER
CONVECTION HAS BECOME PREDOMINANT OVER ERN SD...IN E-CENTRAL SECTOR
OF COLD-CORE UPPER LOW. REMAINING SVR THREAT IS EXPECTED TO BE
RATHER SHORT-LIVED...AND SHOULD DIMINISH SUBSTANTIALLY AFTER DARK.
MLCINH IS FCST TO INCREASE PROHIBITIVELY FOR SFC-BASED PARCELS AFTER
04Z...BASED ON MODIFIED RUC SOUNDINGS AND LBF RAOB ADJUSTED FOR
GREATER BOUNDARY LAYER MOISTURE CONTENT.
..EDWARDS.. 09/03/2009
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
To unsubscribe from WX-STORM send e-mail to LISTSERV@LISTSERV.ILLINOIS.EDU with
"unsub wx-storm" in the body of your message. For more information write cnovy@cox.net.
No comments:
Post a Comment