SPC AC 301701
DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1101 AM CST FRI JAN 30 2009
VALID 311200Z - 011200Z
...NO TSTM AREAS FORECAST...
...SYNOPSIS...
AN UPPER TROUGH IS EXPECTED TO MOVE AWAY FROM THE EAST COAST ON
SATURDAY. IN THE WAKE OF THIS TROUGH...A MORE ZONAL FLOW REGIME
ACROSS MAINLY THE NRN TIER OF THE U.S. IS EXPECTED TO BE REPLACED BY
TROUGHING IN LEE OF THE CANADIAN AND U.S. ROCKIES. THIS WILL OCCUR
AS A RIDGE BUILDS OVER THE ERN PACIFIC/ADJACENT COAST OF WRN NORTH
AMERICA. IN THE LOW LEVELS...A SURFACE HIGH INITIALLY CENTERED
ALONG THE TX COAST WILL SHIFT EWD ACROSS THE GULF OF MEXICO TO THE
SERN STATES...WHILE A SURFACE FRONT PROGRESSES EWD AND SWD FROM THE
NRN PLAINS. THIS BOUNDARY SHOULD EXTEND FROM THE GREAT LAKES SWWD
THROUGH THE LOWER MO VALLEY TO OK AND W TX BY 12Z SUNDAY.
...PART OF SOUTH CENTRAL TX TO THE MIDDLE TX COAST...
LOW LEVEL SSELY WINDS WILL DEVELOP ACROSS THE WRN GULF INTO THE SRN
PLAINS ON SATURDAY ALONG WRN PERIPHERY OF THE DEPARTING SURFACE
HIGH...WITH GRADUAL MOISTENING EXPECTED INTO THE SRN/MIDDLE TX GULF
COAST LATE IN THE FORECAST PERIOD. THIS SLY FLOW SHOULD STRENGTHEN
SATURDAY NIGHT IN RESPONSE TO HEIGHT FALLS ASSOCIATED WITH LEE
TROUGHING OVER THE PLAINS. LOW LEVEL WAA LATE IN THE FORECAST
PERIOD WILL OCCUR BENEATH A PLUME OF STEEP MID LEVEL LAPSE RATES
SPREADING EWD WITHIN SRN STREAM FLOW REGIME. MODELS SUGGEST
ELEVATED CONVECTION IS POSSIBLE SATURDAY NIGHT FROM SOUTH CENTRAL TX
TO THE MIDDLE TX COAST WITHIN WAA REGIME. ALTHOUGH FORECAST
SOUNDINGS SUGGEST A FEW PARCELS COULD BECOME DEEP ENOUGH FOR CHARGE
SEPARATION...THE PRESENCE OF WEAK UPPER FORCING AND WEAK INSTABILITY
SHOULD LIMIT THE TSTM POTENTIAL TO A LESS THAN 10 PERCENT
PROBABILITY.
..PETERS.. 01/30/2009
CLICK TO GET WUUS02 PTSDY2 PRODUCT
NOTE: THE NEXT DAY 2 OUTLOOK IS SCHEDULED BY 0700Z
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