Gale Warning 202, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
140 PM AKDT SUN MAR 21 2010

.ANALYSIS AND UPPER LEVELS...
HIGH AMPLITUDE TROUGH OVER EASTERN SIBERIA RESULTING IN A DOWNSTREAM
RIDGE CENTERED OVER THE WESTERN BERING SEA. A BROAD TROUGH PERSISTS
OVER MUCH OF MAINLAND ALASKA WITH THE ANCHOR LOW LOCATED WELL SOUTH
OF OUR FORECAST AREA OVER THE NORTH PACIFIC. AT THE SURFACE...HIGH
PRESSURE CONTINUES TO DOMINATE THE EASTERN BERING SEA...SURROUNDED BY
TWO WEAK SURFACE TROUGHS WITH LITTLE TO NO PRECIPITATION ASSOCIATED
WITH THEM.

.MODEL DISCUSSION...
MODELS HAVE BEEN INCONSISTENT WITH THE WEAK SURFACE PATTERN ALTHOUGH
UPPER LEVELS AND SYNOPTICALLY LOOKING SIMILAR. THE 12Z RUNS ARE IN
FAIR AGREEMENT...ALTHOUGH GIVE A SLIGHT EDGE TO THE NAM BASED ON RUN
TO RUN CONSISTENCY AND CONTINUITY.

.SHORT TERM FORECAST...
PRECIPITATION LIMITED TO THE COASTAL AREAS THIS AFTERNOON. THE
COVERAGE WILL INCREASE OVERNIGHT AS A SHORT WAVE ROTATES SOUTHWARD
OUT OF BRISTOL BAY INTO THE WESTERN GULF OF ALASKA. AT THE SAME
TIME...ANOTHER SHORT WAVE IS DROPPING OUT OF THE NORTHERN YUKON
TERRITORY. THE TWO SHORT WAVES COUPLED WITH SOME JET SUPPORT FROM THE
NORTHERN PACIFIC WILL HELP DEVELOP A SURFACE LOW MONDAY THAT WILL
BRING GALE FORCE WINDS ALONG THE NORTH GULF COAST MONDAY NIGHT.
CLOUDS AND PRECIPITATION SHOULD REMAIN ALONG THE COASTAL SECTIONS AND
UPSLOPE MOUNTAIN RANGES BUT CAN NOT RULE OUT A STRAY SHOWER OVER
INLAND AREAS GIVEN THE WEAK PRESSURE PATTERN AND ABUNDANCE OF
CYCLONIC CIRCULATION ALOFT.

THE MOSTLY CLOUDY AND SHOWERY REGIME CONTINUES THROUGH MID WEEK WHILE
THE UPPER PATTERN MAKES VERY LITTLE PROGRESS...MAINTAINING THE LONG
WAVE AXIS NEAR THE ALASKA PENINSULA.

SOUTHWEST ALASKA...
LIKEWISE WILL SEE GENERALLY INCREASING CLOUDS WITH SCATTERED SHOWERS
THROUGH EARLY NEXT WEEK. TEMPERATURES WILL REMAIN AT OR ABOVE
CLIMATOLOGICAL NORM FOR THIS TIME OF YEAR. THE WEAK PRESSURE GRADIENT
AND ABUNDANT LOW LEVEL MOISTURE COULD LEND ITSELF TO EXTENSIVE FOG
ALONG THE COAST AND IN LOW LYING AREAS.

ALEUTIANS/BERING SEA...
A STORM FORCE FRONT IS APPROACHING THE WESTERN ALEUTIANS BUT WILL
WEAKEN RAPIDLY AS IT ENCOUNTERS THE HIGH PRESSURE OVER THE CENTRAL
BERING SEA. A WEAK SURFACE OCCLUSION WILL DEVELOP ALONG THE WEAKENING
BOUNDARY AROUND THE CENTRAL ALEUTIANS TUESDAY...AND THEN CONTINUE TO
FILL AS IT BECOMES A VERTICALLY STACKED LOW NEAR THE ALASKA PENINSULA
BY MID WEEK.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...STORM WARNING 176
         GALE WARNING 172 175.
FIRE WEATHER...NONE.

AB MAR 10