Small Craft Advisory 846, NWS Anchorage, AK

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

.MODEL DISCUSSION...
THE MODELS ARE IN VERY GOOD AGREEMENT IN THE SHORT TERM MOVING THE
NEXT STORM INTO THE SOUTHERN GULF WEDNESDAY. THEY ARE ALSO HANDLING
THE INTENSE STORM MOVING INTO THE NORTHERN GULF THURSDAY WITH THE
ECMWF COMING MORE IN LINE WITH THE GFS AND NAM. HPC PREFERS THE GFS
MODEL THROUGH THE MID TERM PERIODS AND THAT IS THE MODEL USED IN THE
MORNING FORECAST PACKAGE.

.ANALYSIS AND UPPER LEVELS...
AN UPPER RIDGE IS CENTERED OVER THE PANHANDLE EXTENDING INTO THE
EASTERN AREAS OF SOUTHCENTRAL WHILE A BROAD UPPER TROUGH COVERS MUCH
OF THE STATE AND THE BERING SEA. 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. AT THE SURFACE AS THE NEXT LOW
APPROACHES THE GULF A SECONDARY TRIPLE POINT LOW WILL DEVELOP. THE
MAIN LOW WILL HOLD BACK SOUTH OF KODIAK WHILE THE SECONDARY LOW MOVES
INTO THE EASTERN GULF WEDNESDAY.

.SHORT TERM FORECAST...
SOUTHCENTRAL...
A LARGE LOW OVER THE NORTHEAST PACIFIC WILL MOVE NORTH AND BECOME
NEARLY STATIONARY SOUTH OF KODIAK ISLAND WEDNESDAY NIGHT.

THE WEATHER FRONT ASSOCIATED WITH THE NORTH PACIFIC WILL MOVE INTO
THE GULF TODAY. RAIN AND STORM/GALE FORCE WINDS AHEAD OF THE FRONT
WILL MOVE INTO THE GULF AND KODIAK ISLAND BY LATE MORNING EARLY
AFTERNOON PUSHING INTO THE CENTRAL GULF COAST LATE TONIGHT WEDNESDAY
MORNING. WIND AND RAIN WILL DIMINISH ALONG THE COAST AS THE FRONT
WEAKENS WEDNESDAY NIGHT.

.SOUTHWEST...
WITH A BRISK NORTHERLY FLOW OVER SOUTHWEST CONDITIONS WILL CONTINUE
TO REMAIN DRY EXPECT FOR SCATTERED RAIN SHOWERS AROUND THE COASTAL
AREAS OF BRISTOL BAY. AS THE LOW MOVES TOWARD THE GULF RAIN AND
STRONG WINDS WILL MOVE INTO THE ALASKA PENINSULA THIS MORNING MORNING
AND WILL PERSIST THROUGH WEDNESDAY NIGHT. EXPECT STORM FORCE WINDS TO
DEVELOP TO THE SOUTH OF THE ALASKA PENINSULA THIS TODAY DROPPING BACK
TO GALES THROUGH WEDNESDAY MORNING.

BERING SEA AND ALEUTIANS...
A BRISK NORTHERLY FLOW WILL CONTINUE OVER THE BERING SEA EXPECT
SCATTERED SHOWERS OVER MOST OF THE AREAS WELL INTO THE WEEK.

.LONG TERM FORECAST...
A SIGNIFICANT STORM MOVES OVER THE GULF THURSDAY NIGHT WEAKENS MOVES
ONSHORE FRIDAY NIGHT AND DISSIPATES. THE MODELS DEAL WELL WITH THIS
LOW BUT BEGIN TO VARY GREATLY BEYOND SATURDAY WITH THE NEXT SERIES OF
SYSTEMS MOVING INTO THE GULF. OUT WEST A DEVELOPING OVER THE SEWARD
PENINSULA WILL DROP DOWN INTO THE BERING SEA THROUGH THE WEEKEND.

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

OCT 09