Gale Warning 695, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 PM AKDT TUE OCT 20 2009

.MODEL DISCUSSION...
THE MODELS ARE IN VERY GOOD AGREEMENT ON THE MOVEMENT OF THE SYSTEMS
OVER THE GULF OF ALASKA THROUGH FRIDAY AFTERNOON. THE EUROPEAN AND
GFS MODELS APPEAR TO HAVE GOOD SOLUTIONS THOUGH THE GFS LOWS ARE A
BIT DEEPER. THE NAM MODEL IS ABOUT 6 TO 9 HOURS SLOW ON STORM
MOVEMENT. A COMBINATION OF THE GFS AND EUROPEAN MODEL APPEARS TO BE
THE BEST SOLUTION TODAY.

.ANALYSIS AND UPPER LEVELS...
AN UPPER RIDGE EXTENDS FROM THE PANHANDLE INTO THE NORTHERN GULF AND
SOUTHCENTRAL ALASKA. AN UPPER LOW WHICH IS VERTICALLY STACKED WITH A
LOW AT THE SURFACE IN THE NORTH PACIFIC IS MAKING ITS WAY TOWARD THE
GULF. TO THE WEST A LARGE STATIONARY UPPER RIDGE IS CENTERED OVER THE
KAMCHATKA PENINSULA. AN UPPER LOW OVER THE NORTHERN INTERIOR
CONTINUES TO STRENGTHEN. AT THE SURFACE, THE WEATHER FRONT ASSOCIATED
WITH THE NORTH PACIFIC LOW IS MOVING TOWARD THE SOUTHERN EDGE OF THE
GULF. CURRENT SATELLITE IMAGES SHOW MULTIPLE WAVE ALONG THE FRONT
WHICH WILL DEVELOP INTO MINOR LOWS OVER THE GULF LATE TONIGHT AND
WEDNESDAY.

.SHORT TERM FORECAST...
SOUTHCENTRAL AK AND THE GULF...
A LARGE LOW OVER THE NORTHEAST PACIFIC WILL MOVE NORTH AND BECOME
NEARLY STATIONARY SOUTH OF KODIAK ISLAND WEDNESDAY. ANOTHER LOW OVER
THE NORTH PACIFIC WILL MOVE INTO THE CENTRAL GULF THURSDAY.

THE WEATHER FRONT WILL MOVE INTO CENTRAL GULF TONIGHT AND WEAKEN OVER
THE NORTHERN GULF WEDNESDAY. A SECONDARY LOW WILL DEVELOP ALONG THE
FRONT TONIGHT AND MOVE INTO THE EASTERN GULF WEDNESDAY THEN DISSIPATE
WEDNESDAY NIGHT. STORM/GALE FORCE WINDS OVER THE CENTRAL GULF WILL
WEAKEN A BIT TONIGHT. RAIN OVER KODIAK ISLAND WILL SPREAD INTO THE
CENTRAL GULF COAST AND PRINCE WILLIAM SOUND WEDNESDAY AND THURSDAY.
RAIN AND SNOW SHOWERS WILL DEVELOP OVER THE COPPER RIVER BASIN AND
SUSITNA VALLEY AS SOME OF THE MOISTURE FROM THE STORM SPREADS INLAND
THURSDAY.

.SOUTHWEST...
NORTHERLY FLOW OVER SOUTHWEST ALASKA WILL CONTINUE BRING DRIER
CONDITIONS TO THE KUSKOKWIM DELTA, MOST OF THE SOUTHERN KUSKOKWIM
VALLEY AND WESTERN BRISTOL BAY. AREAS OF RAIN FROM THE STORM SOUTH OF
KODIAK ISLAND WILL SPREAD INTO EASTERN BRISTOL BAY AND EASTERN
KUSKOKWIM VALLEY WEDNESDAY NIGHT AND THURSDAY. STRONG NORTH WINDS
ACROSS THE ALASKAN PENINSULA AND ALONG THE SOUTHWEST COAST WILL
PERSIST THROUGH THURSDAY.

BERING SEA AND ALEUTIANS...
A BRISK NORTHERLY FLOW WILL CONTINUE OVER THE BERING SEA WITH
SCATTERED SHOWERS OVER MOST OF THE AREAS THROUGH THURSDAY.

.LONG TERM FORECAST...
A SIGNIFICANT STORM MOVES OVER THE GULF THURSDAY NIGHT WEAKENS AND
MOVES ONSHORE OVER THE KENAI PENINSULA FRIDAY NIGHT. ANOTHER LOW
PRESSURE SYSTEM IS EXPECTED TO MOVE INTO THE GULF OVER THE WEEKEND

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...STORM 130 132 150.
         GALES 120 138 140 155 165 180.
FIRE WEATHER...NONE.

OCT 09