Heavy Snow in Alaska, March 30 to 31, 2008

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
338 PM ADT SUN MAR 30 2008

.DISCUSSION...
MODELS SIMILAR THROUGH 36 HOURS AND EVEN WITH ONLY SMALL
DIFFERENCES OUT TO 60 HOURS. GOING WITH GFS SINCE IT HANDLED THE
CURRENT SITUATION VERY WELL AS OPPOSED TO THE NAM WHICH WAS
COMPLETELY OUT TO LUNCH.

ROUND TOP UPPER LEVEL RIDGE OVER CENTRAL PORTION OF THE STATE
USHERING IN COPIOUS AMOUNTS OF MOISTURE IN A GENERALLY WSW FLOW. AS
EXPECTED...PRECIPITATION BEGINNING TO CHANGE OVER TO LIQUID FORM
IN ZONE 215. THIS PRECIPITATION WILL LIKELY CONTINUE THROUGH THE
EVENING AND THEN BECOME FREEZING RAIN BEFORE CHANGING BACK TO SNOW
LATER THIS EVENING.

NOT MUCH COLD AIR LEFT SOUTH OF THE BROOKS RANGE...THEREFORE THE
NEXT IN A SERIES OF LOWS THAT IS APPROACHING THE SOUTHWEST COAST
WILL LIKELY DEPOSIT MUCH MORE LIQUID PRECIPITATION THAN THE
CURRENT LOW DID. THE UPPER LEVEL TROUGH OVER THE WEST COAST WILL
DIG DEEPER AND THE UPPER LEVEL TROUGH OVER THE CENTRAL INTERIOR
WILL SHARPEN THROUGH MONDAY. THIS WILL BRING THE TRAJECTORY OF
THIS NEXT LOW MORE IN LINE WITH WHAT THE NAM WAS INDICATING FOR THE
PRESENT SYSTEM. MOST OF THE PRECIPITATION WILL BE CONFINED THE
WEST COAST ZONES AND THE FARTHEST WESTERN INTERIOR ZONES. EXPECT A
GREAT DEAL OF FREEZING RAIN WITH THIS SYSTEM IN THE CHANGEOVER
PERIODS BETWEEN RAIN AND SNOW. HAVE ISSUED A SLUG OF WATCHES FOR
THE WEST COAST DUE TO THE DECENT PROBABILITY OF FREEZING RAIN AND
DECENT SNOWFALL POTENTIAL.

AMAZINGLY ENOUGH...NO MARINE ADVISORIES HAVE BEEN ISSUED SINCE THE
LOW TRACKS RIGHT THROUGH THE BERING SEA TO THE SEWARD PENINSULA
AND LESSENS THE GRADIENT OVER THAT AREA WHILE THE HIGH OVER THE
ARCTIC WEAKENS AND MOVES AWAY.

MID RANGE SOLUTIONS ARE REMARKABLY SIMILAR EVEN OUT TO 240 HOURS.
THEY ALL INDICATE THAT A DEEP LONG WAVE TROUGH WILL DROP OUT OF
FAR EAST RUSSIA TO BE OVER THE WEST COAST BY FRIDAY AND THEN
SPREAD MUCH COLDER AIR EASTWARD AND THE STATE WILL REMAIN IN A
LONG WAVE TROUGH PATTERN THROUGH THE REMAINDER OF 240 HOURS WHILE
A HIGH AMPLITUDE RIDGE BUILDS IN OVER FAR EAST RUSSIA. THE MODELS
DO NOT CASUALLY FORM THE TROUGH...THEY JUST SORT OF DROP IT IN
WHICH LEADS TO LESS CREDIBILITY. HAVE TO WAIT AND SEE IF SPRING IS
ARRIVING OR ON HOLD AGAIN.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
SNOW ADVISORY FOR AKZ219-AKZ221.

WIND ADVISORY FOR AKZ225-AKZ226.

WINTER WEATHER ADVISORY FOR AKZ216.

WINTER STORM WARNING FOR AKZ215.

WINTER STORM WATCH FOR AKZ207-AKZ208-AKZ209-AKZ210-AKZ211-AKZ212-
AKZ213.
&&

CF MAR 08