Small Craft Advisory 996, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
200 PM AST TUE NOV 27 2007

.MODEL DISCUSSION...MODEL INITIALIZATIONS WHERE TOO FAR WEST AND
ABOUT 5 MB TOO HIGH ON STRONG SURFACE CENTER SOUTH OF THE AK PEN THIS
MORNING. NUMEROUS SHORT RANGE FORECAST ADJUSTMENTS WERE MADE TO
MORNING FORECAST PACKAGE AND LIKELY ON THIS AFTERNOONS. GFS/EC MODELS
ARE IN FAIR AGREEMENT THROUGH 84 HRS. MODEL RUN TO RUN CONSISTENCY
HAS NOT BEEN VERY GOOD...HOWEVER THE STRONG WEST-EAST PRESSURE
GRADIENT SETTING UP OVER THE EASTERN ALEUTIANS/EAST BERING SEA WED
HAS BEEN FAIRLY CONSISTENT. SO WILL LEAN TOWARD THE GFS WITH SOME
MODIFICATION FOR THIS FORECAST PACKAGE.

.ANALYSIS AND UPPER LEVELS...
AS STATED ABOVE...MODEL PRESSURES AND POSITION OF LOW CENTER SOUTH OF
THE AK PEN THIS MORNING WERE OFF. CENTER ON THIS AFTERNOON SAT PIC
SHOWS CENTER ALREADY NORTH OF THE AK PEN. THIS CENTER WILL BECOME THE
DOMINATE CENTER AS OLD PARENT CENTER NEAR UNALASKA WEAKENS. SAT PIC
SHOWS OCCLUDED FRONT EXTENDING ACROSS BRISTOL BAY TO MINOR WAVES OVER
AND SOUTH OF THE GULF OF ALASKA. EXPECT FRONTAL SYSTEM WILL MOVE TO
NEAR THE NORTH GULF COAST TONIGHT...THEN WEAKEN AS WEAK TRIPLE POINT
SAPS ENERGY AS IT MOVES TO OVER THE QUEEN CHARLOTTE ISLANDS WED.

REMNANTS OF TROPICAL SYSTEM IS TAKING SHAPE SOUTH OF THE WESTERN
ALEUTIANS THIS AFTERNOON. SYSTEM IS UNDER FAVORABLE JET POSITION AND
HAS ABUNDANT MOISTURE...SO IT SHOULD CONTINUE TO INTENSIFY. MODELS
DROP CENTER TO THE UPPER 940S OVER THE NEXT 12-18 HOURS THEN WEAKEN
IT OVER THE WESTERN ALEUTIANS WED NIGHT THROUGH THU. NORTH PACIFIC
JET POSITION AND SHARPENING OF UPPER TROUGH INDICATES THAT
SIGNIFICANT SECONDARY CENTERS LIKELY TO DEVELOP ALONG FRONTAL BAND
AND MOVE NORTH INTO THE BERING SEA OVER THE NEXT 60 HOURS. THIS
SHOULD INTENSIFY THE GRADIENT OVER THE EASTERN ALEUTIANS/EAST BERING
SEA WED THROUGH THU.

.SHORT TERM FORECAST...
.EAST...WIND IS THE MAIN WEATHER EVENT THROUGH TONIGHT. PRESSURE
GRADIENTS HAVE INCREASED THIS AFTERNOON AS A STRONG LOW MOVED CROSSED
THE AK PEN. GAP WINDS IN SOUTHCENTRAL SHOULD DIMINISH OVERNIGHT.
STRONG WINDS WITH GALES LIKELY OVER THE GULF AND COASTAL MARINE AREAS
THROUGH THIS EVENING. EXPECT WINDS WILL DIMINISH MOST AREAS AFTER
MIDNIGHT AS THE FRONT MOVES ONSHORE AND WEAKENS. MORE SIGNIFICANT
TRIPLE POINT FORMING SOUTH OF THE GULF SHOULD ROB MOST OF MOISTURE...
SO NOT LOOKING FOR ABNORMALLY HIGH RAIN OR SNOW TO SOUTHCENTRAL OVER
THE GULF COAST.

.WEST...STRONG WINDS OVER SW ALASKA...ESPECIALLY ALONG BRISTOL BAY
AND ALEUTIAN RANGE SHOULD DIMINISH TONIGHT AS LOW CENTER WEAKENS AND
MOVES OFF TO THE NORTHWEST. STRONG SOUTHERLY WINDS SPREAD TO THE
EASTERN ALEUTIANS OVERNIGHT IN ADVANCE OF FRONTAL SYSTEM ASSOCIATED
WITH DEVELOPING LOW NEAR THE WESTERN ALEUTIAN. EXPECT PRESSURE
GRADIENTS ALONG WITH STRONG SOUTHERLY/GAP WINDS TO SPREAD TO THE AK
PEN/EASTERN BERING/PORTION OF SW AK WED. EXPECT STRONG WINDS
CONDITIONS TO HOLD OVER THESE AREAS THROUGH THU AS WAVES MOVE NORTH
ALONG FRONTAL BOUNDARY.

.LONG TERM FORECAST...COLDER AND DRIER CONDITIONS ARE EXPECTED TO
SPREAD WEST OVER THE MAINLAND LATER THIS WEEK AND CONTINUE THROUGH
THE WEEKEND.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...STORMS 170 172 175 176 AND 179.
         GALES 120 130 138 155 160 165 180 171 AND 185.
FIRE WEATHER...NONE.

RMC NOV 07