Small Craft Advisory 692, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
500 PM AKDT MON SEP 9 2013

.ANALYSIS AND UPPER LEVELS...

UPPER LEVEL TROUGH EXTENDS FROM WEST OF KAMCHATKA TO THE ALCAN THIS
AFTERNOON...WITH AN EMBEDDED LOW OVER BRISTOL BAY AND ANOTHER UPPER
LOW SOUTH OF THE KAMCHATKA PENINSULA. AT THE SURFACE...LOW PRESSURE
IN BRISTOL BAY IS HEADED NORTH. AN ASSOCIATED FRONT IS SPREADING RAIN
ON THE WINDWARD SIDE OF THE KENAI AND CHUGACH MOUNTAINS AND THE
ALEUTIAN RANGE. DOWNSLOPING AND DRYING OVER THE ANCHORAGE BOWL AND
PORTIONS OF THE KENAI PENINSULA ARE BEGINNING TO END. WINDS
PERPENDICULAR TO THE MOUNTAINS AT RIDGETOP LEVEL ARE BEGINNING TO
WEAKEN AND RAIN IS ABOUT TO RETURN TO THE LEEWARD SIDE.

A MUCH WEAKER LOW AND ASSOCIATED FRONT ARE ENTERING THE NORTHWESTERN
BERING. THE NEXT MAJOR PLAYER IS A LOW SOUTH OF KAMCHATKA TAKING AIM
AT THE WESTERN ALEUTIANS.

.MODEL DISCUSSION...

MODELS ARE IN FAIR AGREEMENT. THE LOW OVER BRISTOL BAY MOVES NORTH
TONIGHT AND WEAKENS...WHILE THE ASSOCIATED FRONT MOVES TO THE
NORTHEAST GULF COAST TONIGHT INTO TUE AND THEN DISSIPATES. THE
NORTHERN BERING LOW AND FRONT MOVE RAPIDLY EAST AND DISSIPATE TUE
NIGHT NEAR THE PRIBILOFS. THE LOW SOUTH OF KAMCHATKA MOVES TO THE
CENTRAL ALEUTIANS BY WED AFTERNOON AND THE EASTERN ALEUTIANS THU
AFTERNOON. THE ASSOCIATED FRONT WILL BEGIN TO AFFECT THE WESTERN
ALEUTIANS TUE MORNING...THE CENTRAL ALEUTIANS TUE NIGHT INTO
WED...AND THE EASTERN ALEUTIANS AND AK PEN WED INTO THU. THE FORECAST
UTILIZES THE GFS SINCE IT HAS SHOWN THE MOST CONSISTENCY....WITH WPC
GUIDANCE IN THE EXTENDED.

.SHORT TERM FORECAST...

IN THE WEST...SOME SHOWERS WILL ACCOMPANY THE NORTHERN BERING LOW AS
IT TRANSITS TO THE PRIBILOFS OVERNIGHT. THE BRISTOL BAY LOW WILL KEEP
A GRADIENT OVER THE EASTERN BERING WITH SMALL CRAFT WINDS PERSISTING
THROUGH TUE. THE KAMCHATKA LOW WILL BRING RAIN AND SMALL CRAFT TO
GALE FORCE WINDS TO THE WESTERN ALEUTIANS TUE MORNING THROUGH WED
AFTERNOON...THE CENTRAL ALEUTIANS TUE AFTERNOON THROUGH THU
AFTERNOON...AND THE EASTERN ALEUTIANS WED MORNING THROUGH FRI.

FOR SOUTHWEST AK...RAIN AND SHOWERS WILL DIMINISH WED BENEATH A
SHORT-LIVED RIDGE OF HIGH PRESSURE. THE ARRIVAL OF THE KAMCHATKA LOW
WILL BRING SHOWERS BEGINNING THU AND LASTING THROUGH THE WEEKEND.

SOUTH AND EAST OF THE AK RANGE...MOIST ONSHORE FLOW WILL BRING
ABUNDANT RAINFALL TO COASTAL SECTIONS WITH SHOWERS INLAND INTO THE
WEEKEND. DOWNSLOPING OVER THE ANCHORAGE BOWL WILL END TONIGHT AND
RAIN WILL THEN PERSIST THROUGH THE REST OF THE WEEK.

.LONG TERM FORECAST...

THE WEST WILL BE FAIRLY DRY THROUGH THE WEEKEND...WITH RAIN AFFECTING
SOUTHWEST AK UNTIL DRYING BUILDS IN LATE SAT INTO SUN. SE OF TH E AK
RANGE WILL BE AFFECTED BY A FRONT THAT WILL KEEP PRECIPITATION OVER
THE AREA THROUGH THE WEEKEND.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...GALES 120 125 129 172
FIRE WEATHER...NONE

DS SEP 13