Gale Warning 51, NWS Fairbanks, AK

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
301 PM AKDT MON APR 22 2013

.DISCUSSION...

MODELS...IN GOOD AGREEMENT THROUGH 60 HOURS. AFTER 60 HOURS MODELS
CONTINUE TO BE IN RELATIVELY GOOD AGREEMENT EXCEPT FOR THE DETAILS
SO A BLEND WOULD APPEAR TO BE THE WAY TO MOVE FORWARD. ALL MOS
TEMPERATURE GUIDANCE LOOKS TO BE OUT TO LUNCH AFTER WEDNESDAY AS
IT DOES NOT APPEAR TO BE HANDLING THE COLD AIR ADVECTION THAT ALL
THE MODELS SHOW FOR THE REMAINDER OF THE WEEK.

ALOFT...AT 500 HPA...STRONG RIDGE OVER EASTERN BERING AND CHUKCHI
SEAS FLATTENS OUT ALLOWING STRONG SHORT WAVE TROUGH OVER RUSSIA
TO MOVE ACROSS THE NORTHWEST COAST TODAY MERGING WITH THE TOUGH
OVER BRISTOL BAY AND THE SOUTHWEST COAST. THE MERGED TROUGH WILL
LIE FROM THE NORTHEAST COAST SOUTHWEST TO THE ALASKA PENINSULA BY
TUESDAY AFTERNOON. RIDGING OVER THE INTERIOR AND SOUTH CENTRAL
AREA WILL RETREAT SOUTHEAST ALLOWING THE TROUGH TO DRAPE ACROSS
THE INTERIOR TUESDAY NIGHT INTO WEDNESDAY AS IT WEAKENS. THE HIGH
THAT WAS PUSHED PACK OVER THE CENTRAL BERING SEA WILL BUILD BACK
IN OVER THE EASTERN BERING SEA...BRISTOL BAY...AND SOUTHWEST
ACROSS THE GULF OF ALASKA ON THURSDAY. THE LOW ASSOCIATED WITH
THE TROUGH WILL DIG IN OVER THE CANADIAN ARCHIPELAGO WEDNESDAY
NIGHT AND STRONG NORTHWESTERLY TO NORTHERLY FLOW WILL DEVELOP
OVER THE STATE THAT WILL LAST INTO NEXT WEEK. AT 850
HPA...TEMPERATURES FALL FROM AROUND 4 BELOW CELSIUS TODAY TO
AROUND 9 BELOW CELSIUS BY THURSDAY MORNING THEN REMAIN STEADY
THROUGH THE WEEKEND.

SURFACE...1004 MB LOW NEAR 75N 180 WILL MOVE EAST TO 75N 140W BY
TUESDAY NIGHT AT 993 MB THEN TO THE CANADIAN ARCHIPELAGO AS A
993 MB LOW ON THURSDAY MORNING. ASSOCIATED WARM FRONT IS MOVING
ALONG THE ARCTIC COAST THIS EVENING AND WILL MOVE THROUGH BARTER
ISLAND OVERNIGHT. COLD FRONT WILL DRAG ACROSS THE ARCTIC PLAIN
THROUGH THURSDAY MORNING AND MOVE SOUTH INTO THE INTERIOR TUESDAY
EXTENDING FROM FORT YUKON TO KOTZEBUE AND WEDNESDAY FROM EAGLE TO
EMMONAK AS IT DISSIPATES. A SECONDARY COLD FRONT ASSOCIATED WITH
THE LOW WILL DIVE SOUTH OVER THE EASTERN ARCTIC COAST EARLY
THURSDAY. A 1028 MB LOW WILL DEVELOP OVER PRINCE WILLIAM SOUND
TUESDAY NIGHT AND MOVE EAST OVER THE SOUTHERN YUKON TERRITORY
MERGING WITH THE COLD FRONT.

NORTH SLOPE...LIGHT SNOW AND EVEN SOME PERIODS OF FREEZING RAIN
MOVING EAST ACROSS THE AREA TONIGHT. SNOW ACCUMULATIONS WILL
GENERALLY BE AROUND 1 INCH. AS COLD FRONT MOVES INTO BROOKS RANGE
EXPECT SCATTERED SNOW SHOWERS AT LEAST...WHICH MAY LAST INTO EARLY
WED UNTIL FRONT DROPS INTO THE INTERIOR. SOUTHWEST TO WEST WINDS
WILL PREVAIL AT 10 TO 20 MPH...EXPECT SOME GUSTY WINDS TO AROUND
40 MPH AS THE FRONTS MOVE THROUGH. LOCAL GUSTS TO 60 MPH POSSIBLE
THIS EVENING NEAR CAPE LISBURNE. TEMPERATURES WILL COOL BEHIND THE
FRONT WEDNESDAY NIGHT.

WESTERN ALASKA...LINGERING SNOW OR FREEZING RAIN THIS AFTERNOON
ON THE CHUKCHI SEA COAST WILL TAPER OFF. SOUTH WINDS GENERALLY
10 TO 20 ON THE CHUKCHI SEA COAST...FROM THE SEWARD PENINSULA
SOUTH WINDS GENERALLY LESS THAN 15 MPH. AS THE COLD FRONT IN
THE ARCTIC DRIFTS SOUTH WEDNESDAY IT WILL BRING A CHANCE OF SNOW
FROM THE SEWARD PENINSULA NORTH. COOLING TREND LATER IN THE WEEK
WILL EXTEND INTO EARLY NEXT WEEK.

INTERIOR...TEMPERATURES NEAR NORMAL THROUGH WEDNESDAY THEN
COOLING TREND AS NORTHERLY FLOW DEVELOPS ALOFT. AT LEAST FLURRIES
EXPECTED WITH THE COLD FRONT AS IT MOVES INTO THE INTERIOR AND
DISSIPATES. SOME AREAS MAY SEE AROUND AND INCH OF SNOW BUT IT
WILL BE VERY LOCALIZED. AS THE COLD FRONT COMBINES WITH THE LOW
THAT DEVELOPS IN PRINCE WILLIAM SOUND THE EASTERN ALASKA RANGE
ZONES COULD SEE A FEW INCHES OF SNOW AND EVEN SOME RAIN DURING THE
DAY ON TUESDAY IN THE UPPER TANANA VALLEY. TEMPERATURES NEAR
NORMAL THROUGH TUESDAY AFTERNOON BUT COOLING TREND WILL PUSH THEM
SIGNIFICANTLY BELOW NORMAL FOR THE REMAINDER OF THE WEEK AND INTO
EARLY NEXT WEEK.

FIRE WEATHER...WITH COOLING TEMPERATURES SNOW COVER WILL STAY
INTACT FOR MOST AREAS. EVEN WITH THE SNOW COVER IN MANY AREAS
THE RELATIVE HUMIDITY VALUES HAVE DIPPED INTO THE TEENS IN SOME
AREAS...SO AREAS DEVOID OF SNOW WILL BE VERY DRY.

HYDROLOGY...BREAKUP WILL BE  SLOWED AS WE SEE COOLING TREND
BEGINNING WEDNESDAY. THIS COULD LEAD TO SIGNIFICANT ISSUES LATER
IF WE SEE A RAPID WARM UP AND OVERNIGHT TEMPERATURES DO NOT COOL
SIGNIFICANTLY ENOUGH TO SLOW THE MELTING OF THE SNOW PACK.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
BRISK WIND ADVISORY FOR PKZ210-PKZ220-PKZ225-PKZ230-PKZ235.
&&

SDB APR 13