Gale Warning 40, NWS Fairbanks, AK

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
1131 AM AKST THU MAR 7 2013

.DISCUSSION...

MODELS...GOOD AGREEMENT INTO THE MIDTERM CONTINUES SO WILL USE
A BLEND THROUGH THAT POINT. LEANING TOWARD THE ECMWF SOLUTION
FURTHER OUT.

ALOFT...AT 850 HPA...504 DAM CLOSED LOW OVER COLD BAY WILL
CONTINUE NORTH TONIGHT TO OVER ST LAWRENCE ISLAND BY FRIDAY
MORNING...THEN AS IT IS ABSORBED INTO THE LONG WAVE TROUGH.
A CLOSED LOW WILL DEVELOP OVER EASTERN RUSSIA SATURDAY MORNING
AND MOVE TO ST LAWRENCE ISLAND BY SATURDAY EVENING. THIS MARKS
THE BEGINNING OF THE PATTERN CHANGE OVER THE AREA AS THE LONG
WAVE TROUGH STARTS TO WEAKEN AND MOVES EAST WITH A LOW AMPLITUDE
RIDGE BUILDING OVER THE EASTERN BERING SEA AND WEST COAST. AS THE
RIDGE BUILDS THE AMPLITUDE INCREASES AND THE TROUGH DIGS IN OVER
THE WESTERN CANADIAN PROVINCES CREATING STRONG NORTH FLOW OVER
THE EASTERN TWO THIRDS OF THE STATE.
AT 700 HPA...STRONG WINDS CONTINUE INTO FRIDAY ACROSS THE ALASKA
RANGE DIMINISHING BY AFTERNOON FROM 50 TO 70 KT TO AROUND 50 KT.
AT 850 HPA...WARM AIR ADVECTION CONTINUES TONIGHT FOR THE
INTERIOR WITH WARMEST TEMPERATURES OF 2 ABOVE CELSIUS. COLD AIR
ADVECTION BEGINS THIS EVENING ON THE WEST COAST AND THEN MOVES
INTO THE INTERIOR FRIDAY. WITH THE PATTERN CHANGE OVER THE WEEKEND
WILL COME STRONG COLD AIR ADVECTION THAT WILL CONTINUE INTO NEXT
WEEK WITH MODELS CURRENTLY PUSHING TEMPERATURES TO AROUND 25 BELOW
CELSIUS BY MID WEEK.

SURFACE...955 MB LOW NEAR COLD BAY WILL CONTINUE TO MOVE NORTH TO
NEAR NUNIVAK ISLAND BY FRIDAY MORNING AT 977 MB...THEN CONTINUE
TO NEAR THE BERING STRAIT BY FRIDAY EVENING...AND INTO THE
CHUKCHI SEA BY SATURDAY AFTERNOON AT 996 MB. BROAD AREA OF LOW
PRESSURE WILL CONTINUE OVER THE MAINLAND. 1040 MB HIGH NEAR
83 N 150 W WILL SLIP NORTH BUT INTERACTION WITH THE LOW ON THE
WEST COAST WILL TIGHTEN GRADIENT OVER THE ARCTIC COAST TONIGHT
WITH IT REMAINING THAT WAY AT LEAST UNTIL SATURDAY NIGHT FOR THE
COASTAL AREAS. FRONTAL SYSTEM WITH THE LOW ON THE WEST COAST WILL
DRAG NORTH TODAY THEN SLOWLY WORK EAST AS IT FALLS APART. REMNANTS
OF THE FRONT WILL PRODUCE SOME PERIODS OF SNOW OR FLURRIES ACROSS
MUSH OF THE INTERIOR INTO SATURDAY. A 994 MB LOW MOVING FROM THE
WESTERN BERING SEA ON FRIDAY NIGHT WILL APPROACH THE SOUTHWEST
ZONES BY SATURDAY EVENING AS A 1002 MB LOW...IT THEN MOVES
SOUTHEAST TO KODIAK ISLAND BY SUNDAY AFTERNOON.

ARCTIC COAST...A SLIGHT REPRIEVE IN THE WINDS TODAY FOR MOST
AREAS...BUT THEY WILL RETURN WITH A VENGEANCE THIS EVENING
BRINGING BLIZZARD CONDITIONS TO THE COASTAL AND PLAINS AREAS
THAT WILL CONTINUE INTO LATE FRIDAY EVENING. ANY SIGNIFICANT
SNOWFALL WILL BE LIMITED TO THE NORTHWEST COAST THROUGH SATURDAY.

WEST COAST...WINDY CONDITIONS WILL CONTINUE THROUGH THE NIGHT FOR
MOST AREAS. SNOW WILL TAPER OFF FROM THE SOUTH THROUGH THE NIGHT.
A CHANCE FOR SOME FREEZING RAIN WILL CONTINUE THROUGH THE EVENING
FOR THE COASTAL AREAS AND NEAR THE NULATO HILLS. HEAVIEST SNOW
WILL BE NEAR THE COAST...IN THE NULATO HILLS...AND OVER THE
SOUTHERN HALF OF THE SEWARD PENINSULA. TEMPERATURES WILL BE
SLIGHTLY COOLER TONIGHT AND TOMORROW THEN DROP 10 TO 15 F
SATURDAY.

INTERIOR...PRECIPITATION WILL BE SHADOWED OUT WITH THE STRONG
CHINOOK FLOW ACROSS THE ALASKA RANGE. WITH THE WARM AIR ADVECTION
COMES WARMER TEMPERATURES...THEY WILL FALL SLOWLY BEGINNING FRIDAY
AFTERNOON WITH SIGNIFICANT COOLING BEGINNING SATURDAY THAT WILL
CONTINUE INTO NEXT WEEK. LIGHT SNOW OR FLURRIES WILL OCCUR
SATURDAY NIGHT INTO SUNDAY AS THE DISSIPATING FRONTAL SYSTEM
SLIDES EAST. WE WILL ALSO SEE SOME SNOW FALL AS THE STRONGER
COLD AIR ADVECTION PUSHES SOUTH ON MONDAY NIGHT.

MID RANGE...MUCH COLDER NEXT WEEK WITH CLEAR CONDITIONS IN THE
INTERIOR. ALONG THE WEST COAST THEY WILL BE CLOUDY WITH SHOWERS
AND SLIGHTLY ABOVE NORMAL TEMPERATURES.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FOR AKZ223.

HIGH WIND WARNING FOR AKZ225-AKZ226-AKZ227.

BLIZZARD WARNING FOR AKZ201-AKZ202-AKZ203-AKZ204.

WINTER WEATHER ADVISORY FOR AKZ205-AKZ206-AKZ212-AKZ214-AKZ215-
AKZ216.

GALE WARNING FOR PKZ200-PKZ210-PKZ215-PKZ220-PKZ230-PKZ235-
PKZ240-PKZ245.

BRISK WIND ADVISORY FOR PKZ225.
&&

SDB MAR 13