SPC AC 250527
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1127 PM CST FRI NOV 24 2006
VALID 261200Z - 271200Z
...NO SVR TSTM AREAS FORECAST...
...SYNOPSIS...
STRONG HEIGHT FALLS ARE FORECAST FROM THE PACIFIC NW INTO NRN/CNTRL
CA AS INTENSE MID AND UPPER-LEVEL JET STREAKS DIG SEWD FROM THE NERN
PACIFIC OCEAN TOWARD THE GREAT BASIN. AS THIS OCCURS...
AMPLIFICATION OF WRN U.S. TROUGH WILL OCCUR...ANCHORED BY VORTEX
OVER SRN BRITISH COLUMBIA/WA. MEANWHILE...A SUBTROPICAL JET BRANCH
WILL REMAIN ACTIVE WITH SEVERAL EMBEDDED SHORT WAVE TROUGHS
TRANSLATING NEWD THROUGH THE MEAN FLOW REGIME FROM NRN MEXICO TO THE
UPPER GREAT LAKES.
IN THE LOW-LEVELS...ARCTIC COLD FRONT FROM THE NRN ROCKIES INTO
UPPER MS VALLEY WILL SLOWLY PUSH SWD THROUGH THE DAY TWO PERIOD.
ELSEWHERE...A DEEP SURFACE LOW WILL MOVE INTO WA/ORE WITH ATTENDANT
PACIFIC FRONT PUSHING SEWD TOWARD THE GREAT BASIN.
...PACIFIC NW COAST SWD ALONG THE NRN/CNTRL CA COAST...
AS MENTIONED ABOVE...STRONG HEIGHT FALLS ARE FORECAST ACROSS THE
REGION SUNDAY/SUNDAY NIGHT AS MEAN TROUGH INTENSIFIES ON CYCLONIC
SIDE OF MID AND UPPER-LEVEL JET STREAKS DIGGING SSEWD ALONG THE
PACIFIC COAST. AS THIS OCCURS LAPSE RATES WILL STEEPEN OWING TO THE
FORCING/COOLING ALOFT WITH POCKETS OF WEAK CONVECTIVE INSTABILITY
DEVELOPING. IT APPEARS THE BEST POTENTIAL FOR A FEW TSTMS WILL
EXIST ALONG PACIFIC COLD FRONT AS IT APPROACHES THE COAST...AS WELL
AS WITHIN MOIST...POST-FRONTAL ONSHORE FLOW REGIME DEVELOPING SUNDAY
NIGHT.
...UPPER MIDWEST INTO MIDDLE/LOWER MO VALLEY...
LOW-LEVEL MOISTURE IS EXPECTED TO REMAIN RATHER LIMITED WITH
DEWPOINTS COMMONLY IN THE 40S TO PERHAPS LOWER 50S AHEAD OF SURFACE
FRONT. HOWEVER...A PLUME OF RELATIVELY STEEP MID-LEVEL LAPSE RATES
ORIGINATING FROM THE CNTRL ROCKIES WILL BE ADVECTED NEWD INTO THE
REGION AHEAD OF SHORT WAVE TROUGH LIFTING OUT OF THE CNTRL HIGH
PLAINS....EFFECTIVELY CONTRIBUTING TO WEAK CONVECTIVE INSTABILITY.
SUSTAINED FRONTAL CONVERGENCE COUPLED WITH INCREASED LARGE-SCALE
FORCING FOR ASCENT WITH APPROACHING SHORT WAVE TROUGH WILL LIKELY
CONTRIBUTE TO THE DEVELOPMENT OF ISOLATED TSTMS LATE SUNDAY
AFTERNOON INTO SUNDAY NIGHT. SOME SMALL HAIL COULD ACCOMPANY THE
STRONGER STORMS...THOUGH THE MARGINAL INSTABILITY SHOULD PRECLUDE
ANY SEVERE THREAT.
..MEAD.. 11/25/2006
CLICK TO GET WUUS02 PTSDY2 PRODUCT
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 1730Z
|
