Small Craft Advisory 475, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
152 PM AKDT SUN JUN 15 2014

.ANALYSIS AND UPPER LEVELS...

UPPER LEVEL TROUGH EXTENDING FROM EASTERN RUSSIA TO THE ROCKIES
THIS AFTERNOON WITH EMBEDDED LOWS OVER THE CENTRAL ALEUTIANS AND
SOUTHEAST AK. A RIDGE IS CENTERED JUST EAST OF KODIAK ISLAND. A
JET MAX HAS ROUNDED THE CENTRAL ALEUTIAN LOW AND IS PUSHING INTO
THE RIDGE. AT THE SURFACE...LOW PRESSURE OVER THE CENTRAL
ALEUTIANS IS WEAKENING WHILE A SECOND LOW BENEATH THE RIGHT
ENTRANCE REGION OF THE JET IS FORMING WELL SOUTH OF THE AKPEN. A
WAVE ASSOCIATED WITH THE LEFT EXIT REGION OF THE JET IS BEGINNING
TO MOVE NORTHEAST ALONG THE AKPEN. A THERMAL TROUGH IS DRAPED
ALONG THE ALASKA RANGE. HIGH PRESSURE IS OVER MOST OF THE BERING
AND THE NORTHEASTERN GULF.

&&

.MODEL DISCUSSION...

MODELS...WHICH HAVE BEEN WAVERING THE PAST FEW DAYS AND GENERATING
LOW FORECAST CONFIDENCE...HAVE COME TOGETHER OVER THE LAST FEW
RUNS. THE MAIN PLAYER WILL BE THE LOW DEVELOPING SOUTH OF THE
AKPEN. IT WILL MOVE UP THE AKPEN AND INTENSIFY DUE EAST OF KODIAK
MON EVENING...AND THEN DRIFT INTO THE CENTRAL GULF TUE NIGHT
BEFORE DISSIPATING WED AFTERNOON. AN ASSOCIATED FRONT WILL ENTER
THE GULF MON MORNING AND STRENGTHEN UNTIL IT REACHES THE NORTH
GULF COAST MON AFTERNOON. THE ENTIRE SYSTEM THEN WEAKENS IN PLACE
OVER THE GULF THROUGH WED.

WHILE THIS IS HAPPENING...THE THERMAL TROUGH ALONG THE ALASKA
RANGE TODAY WILL DRIFT NORTHWEST AND BEGIN TO PIVOT SO THAT BY WED
IT IS DRAPED BETWEEN THE KUSKOKWIM MOUNTAINS AND THE
ALASKA/ALEUTIAN RANGE. THE WAVE ASSOCIATED WITH THE JET WILL CROSS
SOUTHWEST AK TONIGHT...BUT WILL INTERSECT THE THERMAL TROUGH
DURING PEAK HEATING MON AFTERNOON AND EVENING JUST NORTHWEST OF
THE FORECAST AREA. THE LOW OVER THE CENTRAL ALEUTIANS DISSIPATES
BY MON MORNING AND HIGH PRESSURE BUILDS OVER THE BERING INTO WED.
A SHORT WAVE LOW DIVES OUT OF EASTERN RUSSIA TUE AFTERNOON AND
REACHES THE THE KUSKOKWIM DELTA WITH A FRONT ON WED.

THE EC STILL SEEMS TO BE BRINGING THE INITIAL LOW TOO CLOSE TO
KODIAK ISLAND AND THEN TOO FAR NORTH...WHILE THE GFS AND NAM
REMAIN A BIT MORE TO THE EAST WITH THE LOW AND THEN BRING IT
ACROSS THE GULF AFTER THE ASSOCIATED FRONT HAS DISSIPATED. THE
FORECAST UTILIZE A FAIR AMOUNT OF GFS AND NAM IN THE SHORT TERM.

&&

.SHORT TERM FORECAST...

SOUTHCENTRAL ALASKA...

SHOWERY ACTIVITY WILL CONTINUE ACROSS MUCH OF THE AREA
TONIGHT...WITH SOME EVENING THUNDERSTORMS EXPECTED NEAR THE
TALKEETNA MOUNTAINS AND ALASKA RANGE. RAIN ASSOCIATED WITH THE
FRONT WILL REACH THE COAST ON MON AND INLAND AREAS BY TUE AND
WHERE IT WILL PERSIST INTO WED.

SOUTHWEST ALASKA...

SHOWERS WILL PERSIST THROUGH MID WEEK WITH POSSIBLE AFTERNOON AND
EVENING THUNDERSTORMS IN THE KUSKOKWIM VALLEY THIS
EVENING AND ALONG THE KUSKOKWIM MOUNTAINS AND EAST OF BETHEL ON
MON. A BRIEF BREAK TUE NIGHT WILL THEN BE FOLLOWED BY ANOTHER
ROUND OF SHOWERS WITH THE APPROACHING EASTERN RUSSIA LOW ON WED.

BERING SEA/ALEUTIANS...

THE LOW MOVING ACROSS ALEUTIANS WILL BRING RAIN AND SHOWERS
THROUGH MON NIGHT TO THE EASTERN HALF OF THE CHAIN....WITH DRY
CONDITIONS TRAILING THE LOW. HIGH PRESSURE THEN BUILDS ACROSS THE
AREA WITH SHOWERS LIMITED TO COASTAL LOCATIONS AS THE EASTERN
RUSSIA LOW SLIDES SOUTHEAST WED.

&&

.LONG TERM FORECAST...

THE EXTENDED PERIOD WILL BE SHAPED BY A SYSTEM THAT IS CURRENTLY
DEVELOPING IN THE NORTHERN PACIFIC...SOUTH OF THE CENTRAL
ALEUTIANS. THE RESPONSIBLE UPPER LEVEL LOW WILL BE CENTERED OVER
SOUTHCENTRAL ALASKA WITH SEVERAL EMBEDDED WAVES ROTATING AROUND
IT. THE RESULT WILL BE WETTER AND COOLER TOWARD THE END OF THE
WEEK THEN TRANSITIONING TO MORE SEASONABLE TEMPERATURES OVER THE
WEEKEND. THE CIRCULATION ALOFT STAYS IN PLACE THROUGH EARLY NEXT
WEEK MAKING THE PRECIPITATION FORECAST DEPENDENT ON THE TIMING OF
INDIVIDUAL DISTURBANCES WITHIN THE FLOW...WHICH USUALLY AREN'T
HANDLED QUITE WELL BY GUIDANCE EVEN IN THE SHORT TERM.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALES...120 125 130 131 139 150 155
         STORMS...119 FIRE
WEATHER...NONE.

&&

DS/ML JUN 14