Heavy Snow in Alaska, January 16 to 17, 2008

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
244 PM AST WED JAN 16 2008

.DISCUSSION...ACTIVE WEATHER PATTERN MORE TYPICAL OF OCTOBER OR
NOVEMBER REMAINS IN PLACE. 500MB RIDGE IS CENTERED OFFSHORE OF THE
CONUS AND BRITISH COLUMBIA. A BROAD BAG OF LOW HEIGHTS AT 500MB
COVERS THE NORTHWEST PACIFIC. THIS ARRANGEMENT MEANS ALASKAS WEST
COAST IS SET TO GET HIT BY A SUCCESSION OF SHORT WAVE TROUGHS
MOVING IN FROM THE SOUTH. MOST RECENT EVENT HAS NOW WOUND
DOWN...AND A COMPARATIVELY QUIET REGIME WILL HOLD FOR ANOTHER 48
HOURS OR SO. THEN OVER THE WEEKEND A SIGNIFICANT BERING SEA CYCLONE IS
PROGGED TO DEVELOP. THERE IS SOME MODEL UNCERTAINTY REGARDING THE
DETAILS THIS FAR OUT...BOTH DIFFERENCES BETWEEN THE VARIOUS MODELS
BUT ALSO DIFFERENCES IN THE SAME MODELS FROM RUN TO RUN. WE HAVE
NOT ISSUED ANY WATCHES YET...BUT THAT WILL LIKELY CHANGE OVER THE
NEXT 24 HOURS.

WEST COAST...REMNANT SNOW TONIGHT FROM DYING LOW NOW CENTERED
BETWEEN NOME AND KOTZEBUE. THIS LOW LOOKED GREAT ON THE PAEC 88D
RADAR THIS MORNING...BUT IT HAS SINCE MOVED INLAND AND CONTINUED
TO WEAKEN. EXPECT SNOW AMOUNTS AND WIND SPEEDS WILL REMAIN BELOW
ADVISORY CRITERIA TONIGHT. NEXT BLAST OF HAZARDOUS WEATHER BEGINS
FRIDAY NIGHT. THIS EVENT WILL BE WARMER...AS THE MOST RECENT EVENT
HAS DONE MUCH TO SCOUR OUT THE ARCTIC AIR IN PLACE OVER MUCH OF
THE WESTERN INTERIOR. POSSIBLE THREATS INCLUDE BLOWING SNOW...EVEN
POSSIBLE BLIZZARD OVER COASTAL LOCATIONS...ON LEADING EDGE OF THIS
STORM. THEN POSSIBLE HEAVY SNOW IN UPSLOPE AREAS FURTHER INLAND.
ALSO A CHANCE FOR MIXED RAIN AND SNOW...OR EVEN FREEZING RAIN...IN
THE SOUTHWEST INTERIOR AND YUKON DELTA. MUST REPEAT THAT THERE IS
STILL MUCH UNCERTAINTY THIS FAR OUT IN TIME...BUT THIS WILL BE THE
EVENT TO KEEP AN EYE ON FOR THE NEXT COUPLE DAYS AS IT TAKES
SHAPE.

NORTH SLOPE...WIND CHILL ADVISORIES FOR ZONES 201 AND 202 WILL
CONTINUE THROUGH THIS EVENING DUE TO THE REFUSAL OF THE WIND
SPEEDS TO COME DOWN. DO EXPECT WINDS TO DROP BELOW CRITERIA LATER
TONIGHT. SOME LEFT-OVER MOISTURE FROM THE WEST COAST WILL PRODUCE
MOSTLY CLOUDS AND MAYBE A LITTLE SNOW OVER THE NORTH SLOPE. THE
NORTH SLOPE WILL BE HIT BY THE NEXT EVENT 24-36 LATER THAN THE
WEST COAST...SO THAT IS WAY TOO FAR OUT TO OFFER ANY SPECIFICS
WITH YET.

INTERIOR...SNOW OVER THE SOUTHEASTERN INTERIOR WILL END THIS
EVENING AS THE PARENT FEATURE MOVES FROM THE NORTH GULF COAST INTO
THE YUKON TERRITORY AND DISINTEGRATES. A MORE CONVECTIVE SNOW REGIME
IS TAKING OVER THE INTERIOR TONIGHT...AS EVIDENCED BY QUASI-
CELLULAR LOOK TO SNOW ON PAPD 88D RADAR THIS AFTERNOON. STEERING
FLOW IS PUSHING THESE SNOW SHOWERS ALONG AT A GOOD CLIP...SO EVEN
THOUGH THEY CAN PROVIDE IMPRESSIVE BURSTS OF SNOW THEY CANT DROP
THIS SNOW OVER ANY ONE GIVEN LOCATION FOR MORE THAN A FEW MINUTES.
THUS DO NOT EXPECT SIGNIFICANT ACCUMULATIONS OUTSIDE OF THE
SOUTHEAST INTERIOR. GUSTY SOUTHERLY WINDS AND WARM ADVECTION ARE
POSSIBLE THIS WEEKEND WITH THE APPROACHING STORM. STRONG
MERIDIONAL FLOW SUGGESTS IT WILL BE TOUGH FOR PRECIPITATION TO
MAKE IT EAST OF A LINE FROM ABOUT NENANA TO ATIGUN PASS DUE TO
TERRAIN BLOCKAGE.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...NONE. BERING SEA STORM
THIS WEEKEND WOULD BE MORE WORRISOME FOR AREAS SOUTH OF THE BERING
STRAIT IF THERE WERE NO SEA ICE COVERAGE THERE...BUT SINCE IT IS
MID-JANUARY THE SEA ICE MAKES COASTAL FLOODING AND EROSION
UNLIKELY.

THANKS VERY MUCH WSOS NOME KOTZEBUE AND BARROW FOR YOUR HELP WITH
COORDINATING THE VARIOUS HAZARDS TODAY.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
WIND CHILL ADVISORY FOR AKZ201-AKZ202.

SNOW ADVISORY FOR AKZ224.

BRISK WIND ADVISORY FOR PKZ210.
&&

ES JAN 08