Small Craft Advisory 118, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
500 PM AKST THU FEB 10 2011

.ANALYSIS AND UPPER LEVELS...
A LOW 600 MILES SOUTH OF KODIAK CONTINUES TO WEAKEN AS ENERGY IS
TRANSFERRED TO A TRIPLE POINT LOW DEVELOPING 150 MILES EAST OF KODIAK
CITY THIS MORNING. AN AREA OF HIGH PRESSURE REMAINS SOUTH OF THE
ALEUTIANS WITH A WEAK RIDGE EXTENDING NORTH INTO THE EASTERN BERING.
ANOTHER LOW LIES OVER THE SOUTHERN KAMCHATKA PENINSULA WITH A WEATHER
FRONT EXTENDING EAST INTO THE WESTERN BERING.

.UPPER LEVELS...A STRONG UPPER RIDGE OVER THE EASTERN BERING EXTENDS
NORTH FROM THE HIGH OVER THE NORTH CENTRAL PACIFIC AND WILL BLOCK THE
BERING SEA STORMS FROM ENTERING THE MAINLAND. AN UPPER TROUGH OVER
NORTHERN AND WESTERN ALASKA CONTINUES TO DIG SOUTHWARD AND WILL LINK
UP WITH THE WEAKENING LOW SOUTH OF THE GULF.

.MODEL DISCUSSION...
THE MODELS ARE IN VERY GOOD AGREEMENT THROUGH SATURDAY NIGHT. THE
DEVELOPING LOW OVER THE WESTERN GULF WILL MOVE TO NEAR MIDDLETON
ISLAND AND DEEPEN TO 984 MB TONIGHT THEN BECOME NEARLY STATIONARY
JUST EAST OF MIDDLETON ISLAND THROUGH SATURDAY NIGHT. THE WEATHER
FRONT OVER THE NORTHERN GULF WILL MOVE ONSHORE OVER THE CENTRAL GULF
COAST THEN DISSIPATE TONIGHT. A COLD AIRMASS FROM THE NORTHERN
INTERIOR WILL SPREAD INTO THE SOUTHERN INTERIOR THROUGH FRIDAY AND
WILL INCREASE THE PRESSURE GRADIENT ALONG THE CENTRAL AND WESTERN
GULF COAST OVER THE WEEKEND. THE LOW OVER THE KAMCHATKA PENINSULA
WILL MOVE WILL MOVE EAST AND DISSIPATE OVER THE CENTRAL BERING
SATURDAY. THE ASSOCIATED FRONT OVER THE WESTERN BERING WILL DISSIPATE
OVER THE EASTERN BERING SATURDAY.

THE UPPER TROUGH OVER WESTERN ALASKA WILL MERGE WITH THE LOW SOUTH OF
THE GULF FRIDAY THEN REMAIN NEARLY STATIONARY OVER SOUTHCENTRAL
ALASKA THROUGH SATURDAY NIGHT. AN UPPER LOW OVER THE KAMCHATKA
PENINSULA MOVE EAST AND WEAKEN OVER THE BERING SEA AS IT PUSHES THE
UPPER RIDGE OVER THE EASTERN BERING INTO WESTERN ALASKA FRIDAY.

.SHORT TERM FORECAST...
SOUTHCENTRAL AND THE GULF...RAIN AND SNOW FROM THE WESTERN FRONT OVER
THE NORTHERN GULF WILL SPREAD INTO PRINCE WILLIAM SOUND THIS EVENING
AND INTO THE COPPER RIVER BASIN TONIGHT THEN CHANGE TO SHOWERS
FRIDAY. SOME SNOW WILL SPREAD WEST INTO ANCHORAGE AND THE MATANUSKA
VALLEY TONIGHT AND FRIDAY. STRONG WINDS WILL DEVELOP THROUGH
CHANNELED TERRAIN ALONG THE GULF COAST AND ALONG THE ALASKA RANGE AS
THE GRADIENT INCREASES THROUGH TONIGHT AND FRIDAY.

SOUTHWEST ALASKA...MOST OF THE INTERIOR SECTIONS WILL REMAIN MOSTLY
CLEAR AND COLD THROUGH SATURDAY. CLOUDS AND SNOW WILL MOVE INTO THE
KUSKOKWIM DELTA COAST AND THE ALASKA PENINSULA LATE FRIDAY AS THE
WEATHER FRONT PUSHES INTO THE EASTERN BERING. GUSTY NORTH WINDS OVER
BRISTOL BAY AND THE ALASKA PENINSULA WILL FRIDAY A THE SURFACE RIDGE
OVER THE EASTERN BERING IS PUSHED INTO SOUTHWEST ALASKA.

BERING SEA...RAIN, SNOW AND GALE FORCE WINDS WILL ACCOMPANY THE
BERING SEA WEATHER FRONT THROUGH THE CENTRAL ALEUTIANS TONIGHT THEN
BOTH WIND AND WEATHER WILL DIMINISH OVER THE EASTERN BERING AS THE
FRONT DISSIPATES SATURDAY. WIDE SPREAD SHOWERS WILL REMAIN OVER THE
BERING SEA THROUGH SATURDAY NIGHT.

.LONG TERM FORECAST...
THE UPPER TROUGH OVER EASTERN ALASKA WILL MOVE EAST INTO WESTERN
CANADA AS AN UPPER RIDGE OVER THE WESTERN BERING MOVES INTO MAINLAND
ALASKA TUESDAY. THE LOW OVER THE NORTHERN GULF SATURDAY NIGHT WILL
DISSIPATE SUNDAY NIGHT. RAIN AND SNOW SHOWERS OVER THE COPPER RIVER
BASIN AND PRINCE WILLIAM SOUND WILL DIMINISH SUNDAY.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...GALE...121 129 130 132 138 155 160 165 170 172 175 176 185
         STORM...150
         HEAVY FREEZING SPRAY...150 160 165 185
FIRE WEATHER...NONE.

NM FEB 11