Small Craft Advisory 479, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
400 AM ADT WED MAY 30 2007

.ANALYSIS AND UPPER LEVELS...
ACTIVE WEATHER IS PRESENT ACROSS THE FORECAST AREA THIS MORNING. A
WIDE REACHING AREA OF LOW PRESSURE IS LOCATED JUST EAST OF
ATKA...WITH RAIN ASSOCIATED WITH IT OVER MUCH OF THE BERING AND
ALEUTIANS. A WEAKER...LESS FAR REACHING LOW IS LOCATED NEAR KODIAK
THIS MORNING...ALTHOUGH ITS WINDS ARE ACTUALLY STRONGER THAN THE
ALEUTIAN LOW. THE LOW NEAR KODIAK IS BRINGING RAIN TO THE NORTHERN
GULF AND AND ADJACENT COAST. A WEAKENING SHORTWAVE/UPPER LEVEL LOW
IS MOVING WEST THROUGH THE KUSKOKWIM DELTA THIS MORNING...BRINGING
FROM BETHEL TO KALSKAG. THIS SHORTWAVE WILL MOVE OFFSHORE INTO THE
BERING TODAY. THE LOW NEAR KODIAK WILL DISSIPATE LATE TODAY AND BE
ABSORBED INTO THE WIDER REACHING ALEUTIAN LOW. THE ALEUTIAN LOW WILL
DRIFT SOUTHEAST AND AWAY FROM THE CHAIN LATER TODAY THROUGH
FRIDAY...WHILE A WEAK TRIPLE POINT LOW FORMS TONIGHT ON A TROUGH
EXTENDING EAST FROM THE LOW. THIS NEW LOW WILL PIVOT NORTH AND THEN
WEST THROUGH THE FAR WESTERN GULF AROUND THE EAST AND NORTH SIDE OF
A BROADER CIRCULATION OVER THE FAR WEST GULF/NORTH
PACIFIC...BRINGING CONTINUED RAIN FROM KODIAK TO THE NORTH GULF
COAST INTO FRIDAY.

.MODEL DISCUSSION...
MODELS ARE IN GOOD AGREEMENT THROUGH ABOUT SATURDAY...THEN START TO
HAVE THEIR USUAL DISAGREEMENTS BEYOND THEN.

.SHORT TERM FORECAST...
SOUTHCENTRAL...
THE LOW PRESSURE NEAR KODIAK THIS MORNING WILL FALL APART LATER
TODAY. HOWEVER...A SURFACE TROUGH WILL STILL MOVE THROUGH
SOUTHCENTRAL TODAY AS A WEAK RIDGE OF HIGH PRESSURE WHICH HAD BEEN
PRESENT ALONG THE NORTH GULF COAST FALLS APART. THE TIGHTENING
GRADIENT WILL LEAD TO SOME STRONG WINDS THROUGH TURNAGAIN ARM AND
THE USUAL AREAS LATE TODAY/EARLY THIS EVENING THROUGH AT LEAST
THURSDAY. THE TURNAGAIN ARM WINDS SHOULD MAKE INTO AT LEAST THE WEST
HALF OF ANCHORAGE IN THIS PATTERN. AS FAR AS RAIN GOES...EXPECT IT
TO PERSIST PRETTY MUCH NONSTOP THROUGH FRIDAY FROM CORDOVA TO
PORTAGE TO KODIAK. INLAND AREAS WILL GENERALLY STAY DRY. DESPITE THE
LOW PRESSURE THIS MORNING NEAR KODIAK FALLING APART LATER TODAY...A
NEW TRIPLE POINT LOW WILL FORM TONIGHT SOUTH OF KODIAK AND MOVE
NORTHWEST...ALLOWING THE RAIN AND WIND TO CONTINUE THROUGH FRIDAY
FOR THE USUAL AREAS.

SOUTHWEST MAINLAND...
MAIN FEATURE OF INTEREST TODAY IS A SHORTWAVE/UPPER LEVEL LOW MOVING
WEST THROUGH THE YUKON/KUSKOKWIM DELTA...BRINGING STEADY RAIN. A
WEAK UPPER LEVEL RIDGE IS PRESENT FROM BRISTOL BAY NORTH TO
MCGRATH...BRINGING QUIET WEATHER TO THESE AREAS TODAY.
HOWEVER...CANNOT RULE OUT AN ISOLATED STORM THIS AFTERNOON FROM
SLEETMUTE AND MCGRATH NORTH ON THE NORTH SIDE OF A SURFACE THERMAL
TROUGH. STRONGER AND MORE MOIST SOUTHEAST FLOW WILL KICK IN LATE
TODAY OR TONIGHT ALONG THE ALEUTIAN RANGE...WITH THIS WETTER
SOUTHEAST FLOW OVERTAKING THE ENTIRE SOUTHWEST MAINLAND ON THURSDAY
AND CONTINUING INTO FRIDAY. BECAUSE THIS DIRECTION OF FLOW IS
DOWNSLOPE FOR THE SOUTHWEST MAINLAND...DO NOT EXPECT ANY TERRIBLY
HEAVY PRECIPITATION. HOWEVER...SOME GUSTY WINDS COULD CERTAINLY BE
PRESENT ALONG THE WEST SIDE OF THE ALEUTIAN RANGE BEGINNING THIS
AFTERNOON OR EVENING AND CONTINUING INTO FRIDAY.

BERING SEA/ALEUTIANS...
THE LOW PRESSURE JUST EAST OF ATKA THIS MORNING WILL REMAIN CLOSE TO
STATIONARY TODAY AND TONIGHT...AND THEN MOVE SOUTHEAST AND AWAY FROM
THE ALEUTIAN CHAIN...AND WEAKEN. RAIN AND BREEZY CONDITIONS WILL
CONTINUE OVER THE REGION TODAY AND TONIGHT. THE CENTRAL AND WESTERN
ALEUTIANS AND BERING WILL TEND TO DRY OUT THURSDAY INTO FRIDAY AS
WEAK HIGH PRESSURE BUILDS IN. THE EASTERN ALEUTIANS/BERING WILL KEEP
THEIR RAIN CHANCES THROUGH FRIDAY AS BROAD CYCLONIC CIRCULATION IN
THE FAR WESTERN GULF OF ALASKA BRINGS UNSTABLE EASTERLY TO NORTHEAST
FLOW.

.LONG TERM FORECAST...
KIND OF A COMPLICATED LONG TERM FORECAST WITH SOME PRETTY
SIGNIFICANT MODEL DISAGREEMENT KICKING IN AROUND SUNDAY. SATURDAY
LOOKS FAIRLY SIMILAR TO FRIDAY WITH CYCLONIC CIRCULATION CENTERED
SOMEWHERE OVER THE NORTH PACIFIC OR GULF OF ALASKA...WITH FAIRLY
UNSETTLED WEATHER FROM SOUTHCENTRAL TO THE EASTERN ALEUTIANS/BERING.
FOR SUNDAY AND BEYOND FOR THE BERING AND ALEUTIANS...MOST MODELS AND
MODEL RUNS HAVE SOME SEMBLANCE OF CYCLONIC FLOW AND UNSETTLED
WEATHER WORKING IN THE WESTERN BERING/ALEUTIANS FROM THE WEST AROUND
SUNDAY AND SLOWLY WORKING ITS WAY EAST THROUGH WEDNESDAY...WITH WEAK
HIGH PRESSURE OVER THE CENTRAL TO EASTERN BERING/ALEUTIANS GRADUALLY
GIVING WAY. BEYOND THIS GENERALIZATION...NOT MUCH MORE CAN BE SAID.
FOR THE GULF OF ALASKA AND SOUTHCENTRAL...MOST MODELS AND MODEL RUNS
SHOW SOME SORT OF LOW MOVING NORTHWEST THROUGH THE GULF OF ALASKA
AND AFFECTING THE NORTH GULF COAST MONDAYISH...BUT THE TIMING AND
DETAILS OF THIS ARE A BIT UNCERTAIN. BEYOND MONDAY...THE MODELS ARE
TOTAL SPAGHETTI AND NO REAL ORDER CAN BE DISCERNED AS OF NOW.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...GALE WARNING ZONES 120 AND 130.
FIRE WEATHER...NONE.

FOISY MAY 07