SPC AC 071935
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0135 PM CST SAT NOV 07 2009
VALID 072000Z - 081200Z
...NO SVR TSTM AREAS FORECAST...
...SYNOPSIS...
MOIST LOW-LEVEL WLY UPSLOPE FLOW PERSISTING ACROSS THE PAC NW WILL
CONTINUE TO SUPPORT SHOWERS AND EMBEDDED THUNDERSTORMS...WITHIN
MINIMALLY-UNSTABLE ENVIRONMENT. EXPECT MOST WIDESPREAD CONVECTION
THIS AFTERNOON AND EARLY EVENING...WITH A DECREASING TREND
ANTICIPATED OVERNIGHT.
..GOSS.. 11/07/2009
.PREV DISCUSSION... /ISSUED 1022 AM CST SAT NOV 07 2009/
...WRN PARTS OF WA/OREGON...
STRONG WESTERLY FLOW IS FORECAST TO CONTINUE FROM THE ERN PACIFIC
ACROSS THE NRN PACIFIC COAST AS AN UPPER LOW PERSISTS OVER THE GULF
OF AK. A SERIES OF SHORT WAVE TROUGHS EMBEDDED WITHIN THE MEAN FLOW
ARE MOVING RAPIDLY EWD FROM THE PACIFIC ACROSS WA AND OREGON...WITH
ONE SYSTEM MOVING INLAND ATTM AND AN UPSTREAM SYSTEM FORECAST TO
MOVE ONSHORE LATE THIS AFTERNOON AND EVENING. COLD TEMPERATURES
ALOFT AND ATTENDANT STEEP LAPSE RATES THROUGH APPROXIMATELY 400 MB
ARE RESULTING IN WEAK INSTABILITY WITH MUCAPE AOB 400 J/KG. SEVERAL
PERIODS OF ISOLATED THUNDERSTORMS ARE EXPECTED TO MOVE ONSHORE TODAY
THROUGH THE EVENING HOURS IN ASSOCIATION WITH THE ENHANCED DYNAMIC
FORCING FOR ASCENT ACCOMPANYING THE EWD MOVING SHORT WAVE TROUGHS.
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0100Z
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