High Wind in Alaska, November 21 to 22, 2013

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
240 PM AKST THU NOV 21 2013

.DISCUSSION...

MODELS...BIG PICTURE REMAINS CONSISTENT ACROSS THE MODELS. BUT THE
DETAILS AS YOU GET TO THE SURFACE ARE CONFUSED AT BEST. NAM HAS
A 12Z POP OF 68 PERCENT WHILE THE GFS AT THE SAME TIME HAS A 1
PERCENT POP. NAM HAS A HIGH FRIDAY OF 30 ABOVE...WHILE THE GFS
HAS A HIGH OF 4 ABOVE. WINDS IN THE MODELS ARE ALSO CONFUSING AS
GFS HAS STRONGER WINDS WITH THE COLDER TEMPERATURES. LEANED ON THE
NAM YESTERDAY SO WILL DO THE SAME TODAY FOR THE DETAILS IN THE
SHORT TERM. FOR THE MID AND EXTENDED PERIODS MODELS CONTINUE TO BE
PRETTY DIVERGENT IN SOLUTIONS SO THE WPC APPROACH WITH USE OF THE
ECMWF ENSEMBLE MEAN SEEMS THE BEST APPROACH AT THIS TIME.

ALOFT...AT 500 HPA...528 DAM HIGH CENTER OVER POINT HOPE WILL
WEAKEN AND DISSIPATE TONIGHT. A 507 DAM CLOSED LOW OVER NUNIVAK
ISLAND WILL STRENGTHEN TO 498 DAM OVER CAPE NEWENHAM BY FRI
MORNING THEN DRIFT NORTHEAST OVER THE KUSKOKWIM DELTA BY SAT
MORNING AS IT WEAKENS TO 503 DAM...THEN MOVES TO OVER BARTER
ISLAND AS IT WEAKENS TO 515 DAM BY SUN MORNING. A BRANCH OF THE
RIDGE IN THE PACIFIC IS BUILDING OVER SOUTHEAST ALASKA NOW AND
WILL BUILD NORTH THROUGH FRI MORNING AS IT ROTATES INTO THE YUKON
TERRITORY...THEN IS SLOWLY PUSHED TO THE EAST AS THE LOW OUT WEST
PUSHES UP THE BACK SIDE OF IT. A RIDGE WILL BUILD IN BEHIND THE
THE LOW OVER THE MAINLAND WHILE A BROAD AREA OF LOWER HEIGHT
DEVELOPS OVER THE CENTRAL BERING SEA.

SURFACE...RIDGING OVER THE NORTHEAST INTERIOR WILL BE PUSHED OUT
TODAY AS THE FRONT MOVES TO THE COAST THIS AFTERNOON PUSHING
NORTH ACROSS THE ALASKA RANGE IN OVER THE CENTRAL INTERIOR BY FRI
MORNING. THE FRONT WILL CONTINUE TO ROTATE TO THE NORTHWEST AND
EXTEND FROM THE LOWER YUKON DELTA TO MACKENZIE BAY BY LATE FRI
NIGHT. STILL EXPECT THE HIGHEST QPF VALUES WILL BE OVER THE
SOUTHWEST INTERIOR AND THE ALASKA RANGE THROUGH MID DAY TOMORROW
AND THEN OVER THE EASTERN INTERIOR ZONES NEAR THE BROOKS
RANGE...THEY CONTINUE TO SHOW A QUARTER TO HALF INCH ON THE NAM
WHICH WILL BE THE MODEL OF CHOICE AGAIN TODAY. WEAK HIGH PRESSURE
WILL DEVELOP OVER THE AREA IN THE LEE OF THE LOW AND PERSIST INTO
EARLY NEXT WEEK.

ARCTIC COAST...MOSTLY CLEAR THROUGH THE NIGHT...THEN WINDS PICK
UP ALONG THE EASTERN COAST AND WITH THAT BLIZZARD CONDITIONS WILL
DEVELOP EAST OF BARROW. BLOWING SNOW WILL REDUCE VISIBILITY TO
NEAR ZERO FOR EXTENDED PERIODS OF TIME SO WILL ISSUE BLIZZARD
WARNINGS FOR ZONES 203 AND 204 THAT WILL LAST INTO SAT MORNING.
NORTHEAST TO SOUTHEAST WINDS WILL PERSIST ACROSS THE REMAINDER OF
THE AREA INTO SAT.

WEST COAST AND WESTERN INTERIOR...INCREASING CLOUDS OVER THE
SOUTHERN HALF OF THE AREA WITH SNOW DEVELOPING OVERNIGHT. HIGH
SNOW AMOUNTS STILL EXPECTED IN THE MIDDLE YUKON VALLEY MAY CREEP
INTO THE EASTERN NULATO HILLS. STRONG WINDS ALOFT WILL MAKE IT
INTO THE ALASKA RANGE WITH SOUTHEAST WINDS GUSTING TO 45 MPH NEAR
THE RANGE. MODELS DO SHOW SOME POTENTIAL FOR A LOW LEVEL JET ALONG
THE KUSKOKWIM MOUNTAINS THIS EVENING SO EXPECT SOME GUSTY WINDS IN
ZONES 214...215...227 THIS EVENING...THEN IN THE MIDDLE YUKON
VALLEY OVERNIGHT AS THE SYSTEM PROGRESSES NORTH. TEMPERATURES
WILL BE ON THE RISE TODAY WITH NOT MUCH DIURNAL SWING TONIGHT AS
WARM AIR ADVECTION CONTINUES.

INTERIOR...TEMPERATURES ON THE RISE AS LOW AND ASSOCIATED FRONT
PUSH NORTH TO THE ALASKA RANGE TONIGHT. WITH GAP WINDS DEVELOPING
THROUGH THE ALASKA RANGE TEMPERATURES WILL JUMP 40 TO 60 DEGREES
IN SOME LOCATIONS WITH HIGHS REACHING THE TEENS IN SOME AREAS FRI
AFTERNOON. EXPECT A SHOT OF SNOW OVER THE INTERIOR IN THE MORNING
WITH HEAVY SNOW DEVELOPING TONIGHT IN THE ALASKA RANGE. AS THE
SYSTEM MOVES NORTH HEAVY SNOW MAY BE A PROBLEM IN THE ZONES ALONG
THE SOUTH SLOPE OF THE BROOKS RANGE...ESPECIALLY AROUND COLDFOOT
AND WISEMAN. WINDS STILL ON SCHEDULE TO CREATE ISSUES AROUND IN
THE INTERIOR AS THEY COME UP OVER THE HILLS TONIGHT AND WORK INTO
THE VALLEYS TOMORROW. TANANA VALLEY JET IS IN FULL VOICE TODAY AS
WINDS AROUND DELTA ARE GUSTING TO AROUND 50 MPH...THEY WILL REMAIN
STRONG THROUGH AT LEAST MID DAY FRIDAY.

&&

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...NONE.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
BLIZZARD WATCH FOR AKZ203-AKZ204.

BLIZZARD WARNING FOR AKZ225-AKZ226.

HIGH SURF ADVISORY FOR AKZ213.

WIND ADVISORY FOR AKZ223.

WINTER STORM WATCH FOR AKZ215-AKZ216.

WIND CHILL ADVISORY FOR AKZ223-AKZ224.

WINTER WEATHER ADVISORY FOR AKZ219-AKZ220-AKZ221-AKZ222.

HEAVY FREEZING SPRAY WARNING FOR PKZ200-PKZ210-PKZ220-PKZ225.

GALE WARNING FOR PKZ200-PKZ210-PKZ235-PKZ240-PKZ245.

SMALL CRAFT ADVISORY FOR PKZ220.

BRISK WIND ADVISORY FOR PKZ215-PKZ225-PKZ230-PKZ235-PKZ240-
PKZ245.
&&

SDB NOV 13