Small Craft Advisory 146, NWS Fairbanks, AK

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
359 PM AKDT SAT OCT 22 2011

.DISCUSSION...
THE IMPORTANT INCOMING WEATHER SYSTEM FOR THE NEXT FEW DAYS IS A
STRENGTHENING LOW PRESSURE SYSTEM NOW A 985 MB CENTER IN THE
CENTRAL BERING SEA. OVER THE PAST 6 DAYS THE COMPUTER WEATHER
FORECAST MODELS HAVE HANDLED THIS SYSTEM PRETTY WELL AND
CONSISTENTLY. YESTERDAY EVENINGS NAM MODEL RUN FORECAST THIS LOW
TO MOVE TOO RAPIDLY EASTWARD. THIS MORNINGS NAM MODEL RUN
FORECASTS THE LOW TO BE IN WESTERN BRISTOL BAY ON MONDAY...WHILE
THE GFS MODEL FORECASTS THE LOW TO BE IN KUSKOKWIM BAY ON MONDAY.

THE GFS MODEL FORECASTS THE LOW TO SPLIT INTO A STRONG SOUTHERN
CENTER AND A WEAKER NORTHERN ONE ON MONDAY NIGHT. THE GFS
FORECASTS THE SOUTHERN LOW IS FORECAST TO STRENGTHEN TO A 968 MB
CENTER NEAR KODIAK ON TUESDAY AFTERNOON.

THE NORTHEASTERLY CIRCULATION AROUND THIS LOW PRESSURE SYSTEM WILL
BE AFFECTING ALL OF THE COAST FROM BARROW TO THE YUKON DELTA BY
SUNDAY MORNING. ON MONDAY...NORTHERLY WINDS ON THE BACK SIDE OF
THE LOW ARE EXPECTED TO REACH 20 TO 30 MPH BETWEEN THE YUKON DELTA
AND POINT HOPE. FROM POINT HOPE TO PRUDHOE BAY...EAST WINDS ARE
EXPECTED TO INCREASE TO 25 TO 40 MPH STARTING MONDAY EVENING AND
TO CONTINUE THROUGH WEDNESDAY. FOLLOWING THAT...THIS SOUTHERN LOW
WILL NO LONGER BE AFFECTING NORTHERN ALASKA WEATHER. THE WEAK
NORTHERN LOW IS EXPECTED TO BE OVER EASTERN NORTON
SOUND...SURROUNDED BY SCATTERED SNOW SHOWERS.

IN THE BROOKS RANGE...NORTHEAST WINDS ARE EXPECTED TO REACH THEIR
PEAK ON TUESDAY NIGHT AND WEDNESDAY. THIS COULD BE ACCOMPANIED BY
SNOW AND EXTENSIVE BLOWING SNOW...AND PERHAPS BE THE HEAVIEST
WEATHER ASSOCIATED WITH THE LOW.

THE LONG LIVED LONG WAVE TROUGH ALOFT HAS REMAINED THE PRINCIPAL
LARGE SCALE FEATURE IN CIRCULATION ALOFT. HOWEVER...THERE WILL BE
SOME HIGH PRESSURE ALOFT BUILDING OVER THE YUKON AND THE EASTERN
INTERIOR ON MONDAY...AHEAD OF THE LOW. THIS IS EXPECTED TO BRING
STRONG SOUTH WINDS THROUGH PASSES OF THE ALASKA RANGE MONDAY
THROUGH TUESDAY. TEMPERATURES IN THE EASTERN INTERIOR ARE EXPECTED
TO RISE CLOSE TO FREEZING MONDAY...BUT TO BEGIN FALLING TUESDAY
NIGHT AS THE SOUTH WINDS SUBSIDE.

THIS AFTERNOONS POLAR ORBITING SATELLITE IMAGERY SHOWS A BAND OF
OVERCAST STRATOCUMULUS AND ALTOSTRATUS OVER NEARLY ALL OF THE
INTERIOR. THERE ARE CLEAR SKIES OVER THE LOWER NOATAK
VALLEY...MOST OF THE COASTAL WATERS FROM POINT LAY TO
SHISHMAREF...AND NORTHERN NORTON SOUND.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...NONE

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
HEAVY FREEZING SPRAY WARNING FOR PKZ220-PKZ225-PKZ230-PKZ235-
PKZ240-PKZ500-PKZ505.

SMALL CRAFT ADVISORY FOR PKZ220-PKZ225-PKZ230-PKZ235-PKZ240.
&&

TF OCT 11