SPC AC 140038
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0738 PM CDT FRI OCT 13 2006
VALID 140100Z - 141200Z
...NO SVR TSTM AREAS FORECAST...
...SWRN U.S...
WELL DEFINED UPPER LOW OFF THE SRN CA COAST IS MOVING SLOWLY EWD AT
ROUGHLY 10 KT...WELL HANDLED BY LATEST SHORT RANGE MODEL GUIDANCE.
DOWNSTREAM...WARM CONVEYOR HAS RECENTLY BECOME
CONVECTIVELY-ACTIVE...ESPECIALLY ALONG THE LOWER CO RIVER VALLEY.
DEEP CONVECTION WITH STRONG/SUSTAINED UPDRAFTS HAVE EVOLVED WITHIN
THIS FAVORABLE SHEARED ENVIRONMENT. ALTHOUGH THERMODYNAMIC PROFILES
ARE NOT TERRIBLY UNSTABLE THEY DEPICT VERY STEEP LAPSE RATES WHICH
ARE MORE THAN ADEQUATE FOR ROBUST THUNDERSTORM DEVELOPMENT GIVEN THE
LARGE SCALE SUPPORT. ADDITIONALLY...COLD MID LEVEL TEMPERATURES
BENEATH THE UPPER LOW WILL CONTINUE TO SUPPORT LOCALLY STRONG STORMS
THAT WILL ROTATE WWD OFF THE HIGHER TERRAIN TO THE NORTH OF THE LA
BASIN REGION. IN BOTH REGIONS IT APPEARS UPDRAFT INTENSITY SHOULD
SUPPORT AT LEAST LOW PROBABILITIES FOR ISOLATED LARGE HAIL OR
PERHAPS LOCAL SEVERE WIND GUST. LOSS OF DAYTIME HEATING SHOULD
WEAKEN UPDRAFT STRENGTH/INTENSITY WITH THIS ACTIVITY...ALTHOUGH
CONVECTIVE THREAT SHOULD CERTAINLY SPREAD INLAND AS UPPER LOW MOVES
INTO SRN CA.
DOWNSTREAM...ISENTROPIC ASCENT ACROSS NERN MEXICO/SRN TX SHOULD
MAINTAIN CONVECTIVE THREAT THROUGH THE PERIOD. ALTHOUGH STRONGEST
STORMS WILL DEVELOP/PERSIST JUST EAST OF THE ORIENTAL MOUNTAINS
WHERE INSTABILITY/UPSLOPE IS CONSIDERABLY GREATER.
...GREAT LAKES...
DEPTH OF CONVECTION SHOULD GRADUALLY DECREASE ACROSS MUCH OF THE
GREAT LAKES OVERNIGHT...ESPECIALLY OVER THE LOWER LAKES AS INVERSION
LOWERS AND LOW LEVEL LAPSE RATES WEAKEN WITH TIME. LIGHTNING SHOULD
PROVE QUITE ISOLATED WITH THE GREATEST THREAT FROM THE ERN U.P. OF
MI...SEWD TOWARD GEORGIAN BAY.
..DARROW.. 10/14/2006
CLICK TO GET WUUS01 PTSDY1 PRODUCT
NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0600Z
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