SPC AC 080553
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1153 PM CST SAT NOV 07 2009
VALID 091200Z - 101200Z
...NO SVR TSTM AREAS FORECAST...
...SYNOPSIS...
PROGRESSIVE UPPER FLOW WILL PREVAIL THROUGH MONDAY WITH MAIN BELT OF
WLYS PERSISTING OVER THE NRN THIRD OF U.S.. SERIES OF IMPULSES WILL
ADVANCE EAST WITHIN NRN STREAM INCLUDING THE SHORTWAVE TROUGH NOW
MOVING THROUGH THE NRN ROCKIES. THIS FEATURE WILL REACH NRN MN EARLY
MONDAY...CLOSELY FOLLOWED BY A SECONDARY UPSTREAM SHORTWAVE TROUGH.
ATTENDANT COLD FRONT WILL EXTEND SWWD FROM A SURFACE LOW NEAR SRN
ONTARIO THROUGH THE MID MS VALLEY AND CNTRL PLAINS THEN MOVE SEWD
DURING THE DAY. FARTHER SOUTH...UPPER LOW NOW OVER NRN MEXICO WILL
MOVE INTO THE NWRN GULF AND LOWER MS VALLEY. TROPICAL STORM IDA IS
FORECAST BY NHC TO MOVE INTO THE N-CNTRL GULF...BUT IS CURRENTLY
EXPECTED TO REMAIN OFFSHORE THIS PERIOD.
...GULF COASTAL REGION...
TREND HAS BEEN TO INCREASE THE FORWARD SPEED OF TROPICAL STORM IDA
AFTER IT BEGINS TO INTERACT WITH STRONGER MID-UPPER FLOW EAST OF THE
EWD MOVING UPPER TROUGH NOW OVER MEXICO. CURRENT INDICATIONS ARE
THAT IDA MAY APPROACH THE CNTRL GULF COASTAL AREA LATE MONDAY NIGHT
BUT IS EXPECTED TO REMAIN OFFSHORE AT LEAST UNTIL TUESDAY. SEE
DISCUSSIONS FROM NHC FOR MORE INFORMATION ON IDA. UNLESS IDA
ACCELERATES NWD MORE THAN CURRENTLY FORECAST...THE MOIST WARM SECTOR
AND ANY SEVERE THREAT SHOULD REMAIN OFFSHORE. OTHERWISE...DEEP
TROPICAL MOISTURE WILL ADVECT NWD IN ADVANCE OF THIS SYSTEM
RESULTING IN A THREAT OF WIDESPREAD SHOWERS AND ISOLATED
THUNDERSTORMS ALONG THE GULF COASTAL AREA.
...CNTRL PLAINS THROUGH MID MS VALLEY REGION...
MODIFIED CP AIR RETURNING NWD THROUGH WARM SECTOR WILL RESULT IN AN
AXIS OF WEAK INSTABILITY IN VICINITY OF FRONT WHERE COOLER
TEMPERATURES ALOFT ACCOMPANYING THE UPPER TROUGH WILL CONTRIBUTE TO
MODERATELY STEEP MID LEVEL LAPSE RATES. A FEW NON-SEVERE
THUNDERSTORMS WILL BE POSSIBLE WITHIN ZONE OF DEEPER ASCENT ALONG
THE SEWD ADVANCING FRONT PRIMARILY FROM NRN OK INTO KS AND THE MID
MS VALLEY.
..DIAL.. 11/08/2009
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 1730Z
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