Gale Warning 529, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
200 PM AKDT TUE SEP 10 2013

.ANALYSIS AND UPPER LEVELS...
THERE IS A BROAD UPPER LOW OVER THE BERING SEA AND WESTERN ALASKA.
ASSOCIATED WITH THIS LOW IS AN UPPER TROUGH ALONG THE COAST OF
SOUTHWEST ALASKA AND INTO THE WESTERN GULF OF ALASKA IS MOVING
SLOWLY NORTHEAST...AND AN UPPER LOW JUST SOUTH OF THE WESTERN
ALEUTIANS MOVING RAPIDLY EASTWARD IN THE SUB-TROPICAL JET. A STRONG
RIDGE IS OVER BRITISH COLUMBIA. A FAIRLY STRONG JET (120 KTS)
BETWEEN THE BERING LOW AND B.C. HIGH IS PUSHING INTO THE NORTHERN
PANHANDLE/SOUTHEAST CORNER OF ALASKA.

.MODEL DISCUSSION...
THE NUMERICAL MODELS ARE IN GOOD AGREEMENT FOR THE NEXT 84 HOURS.
THUS THE CONFIDENCE IN THE FORECAST IS FAIRLY HIGH.

.SHORT TERM FORECAST...
FOR SOUTH CENTRAL ALASKA...THE SOUTHWEST ALASKA UPPER TROUGH WILL
SLOWLY MOVE NORTH THROUGH SOUTH CENTRAL ALASKA TONIGHT AND WEDNESDAY
AND FINALLY EXIT INTO EAST CENTRAL ALASKA WEDNESDAY NIGHT. EXPECTING
SHOWERS TO CONTINUE TONIGHT AND DIMINISH ON WEDNESDAY...BASICALLY
ENDING WEDNESDAY EVENING AS THE TROUGH EXITS AND A SHORT-WAVE RIDGE
BUILDS INTO THE AREA.

THE NEXT SYSTEM DUE INTO THE AREA IS THE ONE CURRENTLY SOUTH OF THE
WESTERN ALEUTIANS. INITIAL FRONTAL PRECIPITATION AND WINDS FROM THIS
SYSTEM WILL REACH KODIAK ISLAND THURSDAY MORNING AND INTO THE REST
OF SOUTH CENTRAL ALASKA THURSDAY AFTERNOON/EVENING.

BY FRIDAY THE UPPER FLOW WILL BE QUITE AMPLIFIED WITH THE B.C. RIDGE
STILL IN PLACE AND A RIDGE OVER THE CENTRAL BERING SEA AND CENTRAL
ALEUTIANS. THIS WILL KEEP THE MAIN UPPER LOW OVER THE GULF OF ALASKA
AND IT WILL SLOW CONSIDERABLY. THE WEEKEND MAY ACTUALLY BE DRY AS
THE LOW BECOMES ALMOST CUT OFF FROM THE STORM TRACK AND AND DRIFTS
SOUTH...ALLOWING THE BERING RIDGE TO NOSE INTO SOUTHERN ALASKA.

SOUTHWEST ALASKA...WITH THE UPPER LEVEL TROUGH CONTINUING TO LINGER
OVER SOUTHWEST ALASKA THROUGH WED MORNING...SCATTERED SHOWERS WILL
CONTINUE TO BE OBSERVED OVER MOST OF THE AREA. RIDGING AHEAD OF THE
ALEUTIAN LOW WILL PUSH INTO SOUTHWEST ALASKA BY EARLY WED
MORNING...TEMPORARILY ENDING SHOWERS. AN OCCLUDED FRONT ASSOCIATED
WITH THE ALEUTIAN LOW WILL BRING SHOWERS AND GUSTY WINDS BACK INTO
THE FORECAST BY EARLY THURSDAY MORNING.

BERING SEA AND ALEUTIANS...A NORTH PACIFIC LOW CONTINUES TO TRACK
TOWARD THE CENTRAL ALEUTIANS. GIVEN THE SUBTROPICAL INFLUENCE AND
MODEL AGREEMENT ON A STRONG UPPER LEVEL JET...THE LOW IS EXPECTED TO
INTENSIFY AS IT MOVE OVER THE CENTRAL ALEUTIANS...BRINGING STRONG
AND GUSTY WINDS ALONG WITH STEADY PRECIPITATION TO THE AREA. AS THE
LOW CONTINUES TO TRACK EASTWARD ALONG THE ALEUTIAN CHAIN...GUSTY
WINDS AND RAIN WILL MOVE INTO THE EASTERN ALEUTIANS BY WED MORNING
AND CONTINUE THROUGH THE END OF THE WEEK.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...STORM WARNING 172.
         GALE WARNING 150 155 160 165 170 171 175.
FIRE WEATHER...NONE.

LUDWIG/PEPE SEP 13