470
FXUS02 KWBC 051855
PMDEPD
EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
153 PM EST THU NOV 05 2009
VALID 12Z SUN NOV 08 2009 - 12Z THU NOV 12 2009
MEDIUM RANGE MODELS AND MEANS FROM THE 00Z RUNS ARE IN GOOD
AGREEMENT WITH A TREND TOWARDS CONSOLIDATION TO A BETTER AGREEMENT
COMPARED TO THE WIDE RECENT SPREAD OF SOLUTIONS. TWO SHORTWAVES
CROSS CONUS THIS PERIOD WITH THE FIRST COMING INTO THE WEST COAST
DAY 3 WITH MODERATE AMPLIFICATION AS IT REACHES THE EAST COAST DAY
6 WEDNESDAY WITH ONLY CMC HAVING A HIGH AMPLITUDE SOLUTION. NEXT
STRONGER EPAC SHORTWAVE REACHES THE WEST COAST AROUND DAY 5 WITH
ENOUGH TIMING SPREAD TO PREFER A MODEL AND ENS BLEND CONSENSUS.
UPDATED MORNING PRELIMS USE A COMBINATION OF OPERATIONAL 00Z MODEL
RUNS OF ECMWF/GFS AND THE NEWER 06Z GFS TO ACCOUNT FOR SHORTWAVE
TIMING AND HANDLING OF GULF OF MEXICO LOW PRESSURE.
AFTERNOON FINALS...
12Z MODEL GUIDANCE SHOWING DIFFERENCES WITH THE LEAD SHORTWAVE AS
IT MOVES ACROSS THE NRN TIER OF STATES TOWARDS THE UPPER MS VALLEY
AND WRN GREAT LAKES WITH CONSIDERABLY MORE AMPLIFICATION BY 12Z
GFS/UKMET WHICH DIFFER AS UKMET CLOSES OFF A DEEP STRONG MID LEVEL
LOW OVER ALABAMA WITH GFS EJECTING A CLOSED MID LEVEL LOW INTO NEW
YORK AT DAY 6 WED. THE EARLIER HIGHLY AMPLIFIED CMC IS IN THE
MIDDLE WITH A SHARP TROF OVER WEST VIRGINIA. UKMET AND CMC CONT TO
BE QUITE FAST WITH EJECTING TROPICAL LOW PRESSURE NWD FROM THE
GLFMEX. THESE MODEL SCENARIOS ARE VASTLY DIFFERENT AT THE SFC OVER
THE ERN THIRD OF CONUS. LATEST 12Z GEFS MEAN AND 12Z ECMWF OFFER A
COMPROMISE SOLUTION AND WILL BE USED FOR FINALS FROM DAY 3
ONWARDS.
FOR DAY 3 SUN HIGH PRESSURE DOMINATES THE EAST AND WEST COAST WITH
BOTH HIGHS PROGRESSING EWD. DEEP BROAD EASTERLY FLOW CONTS INTO
THE SOUTHEASTERN SEABOARD AND ACROSS THE GULF OF MEXICO WITH A
LOWERING OF WRN GULF PRESSURES TO AN INVERTED SFC TROF OR A
DEFINED AREA OF LOW PRESSURE IN THE STRONG EAST FLOW. THIS WILL
SPREAD IN MODERATE TO HEAVY GULF COASTAL RAINS FROM SOUTHEAST TX
TO THE FL PANHANDLE AND NWD INTO MS/AL/GA AND NWD UP THE
APPALACHAINS AND TO THE EAST COAST FROM MON TO WED. SOUTHWARD T.S.
IDA EXPECTED TO SLOWLY MOVE NWD ALONG YUCATAN OR THE YUCATAN
CHANNEL INTO THE GULF MEXICO BY DAY 5 WITH A MOVEMENT INTO A MORE
HOSTILE NON TROPICAL ENVIRONMENT. COORDINATED NHC/HPC DAYS 6-7
POSITIONS FOR IDA OR ITS REMAINS ARE DEPICTED AS AN EAST CENTRAL
GLFMEX LOW ENHANCED BY STRONG E-NE FLOW FROM HIGH PRESSURE OVER
THE MID ATLC REGION. POTENTIAL WIDESPREAD HEAVY RAIN SET UP FOR
MUCH OF FLORIDA LATE NEXT WEEK. SEE NHC ADVISORIES FOR IDA.
WESTWARD THE NEXT COLD FRONT AND MID LEVEL TROF COMES INTO THE
WEST COAST MONDAY KEEPING UP THE WET CONDITIONS OVER THE PACIFIC
NORTHWEST AND SPREADING RAIN DOWN THE INTO RAIN TO CENTRAL CA
COAST AND HIGHER ELEV SNOWS WOFKING EWD INTO THE NRN AND CENTRAL
ROCKIES LATE WEEK. ROSENSTEIN
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page