Small Craft Advisory 988, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
1212 PM AKST FRI DEC 4 2009

.MODEL DISCUSSION...GFS AND NAM IN GOOD AGREEMENT ON THE CURRENT
ALEUTIAN LOW PRESSURE SYSTEM...SOME DIFFERENCES IN CENTRAL PRESSURE
AND DEGREE OF ELONGATION...BUT OVERALL PICTURE IS THE SAME.  THEY ARE
ALSO IN GOOD AGREEMENT ON THE SECOND SYSTEM THAT MOVES JUST SOUTH OF
THE ALEUTIANS ON SUNDAY.

.ANALYSIS AND UPPER LEVELS...IN THE UPPER TROPO THE HIGH AMPLITUDE
RIDGE OVER THE GULF OF ALASKA IS WELL ENTRENCHED WITH JET DIRECTLY
OVER THE AK PEN.  SOME WEAKENING OF THE JET SAT AFTERNOON AND EVENING
BUT REINTENSIFIES SUNDAY MORNING AS SECOND LOW MOVES NORTHWARD.

.SHORT TERM FORECAST...VERY STRONG WINDS ACROSS MOST OF THE ALEUTIANS
AND AK PEN WITH WINDY AND BLIZZARD CONDITIONS OVER A CONSIDERABLE
PART OF SOUTHWEST ZONES.  LOOKS AS IF PRESSURE GRADIENT OVER THE
GREATER EASTERN BERING REGIONS WEAKENS SAT MIDDAY. SOME STRONG SE
WINDS OVER KODIAK ISLAND TONIGHT BUT BELOW HIGH WIND WARNING
CRITERIA.
LOOKS AS IF SECOND SYSTEM IS NEARLY A REPEAT OF THE FIRST.  VERY
STRONG WINDS IMPACT EASTERN ALEUTIANS AND AK PEN LATE SAT NIGHT.
BASED ON GFS WINDS SHOULD DIMINISH OVER AK PEN SUNDAY NIGHT AND OVER
EASTERN ALEUTIANS LATE MONDAY MORNING.

.LONG TERM FORECAST...HIGH AMPLITUDE GULF RIDGE MORPHS INTO A HIGH
CENTERED OVER THE KENAI PEN THROUGH MOST OF NEXT WEEK...WITH A SERIES
OF WEAKER LOWS MOVING FROM THE NORTH PACIFIC ACROSS THE ALEUTIANS.
MOST OF THE MAINLAND ZONES WILL BE DRY WITH SEASONABLE TEMPS.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...HWW 195 161 181 185   BLIZZ 191 155
MARINE...STRMS AND GALES WEST OF 150W
FIRE WEATHER...NONE

JMP DEC 09