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000
FXAK68 PAFC 092300
AFDAFC

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
200 PM AKDT SUN MAR 9 2014

.ANALYSIS AND UPPER LEVELS...
A WEAKENING LOW OVER THE NORTH GULF WAS PRODUCING SNOW SHOWERS OVER
THE CENTRAL AND EASTERN GULF AND OVER THE SE COPPER RIVER BASIN.
STRONG GAP FLOWS OVER THE EASTERN KENAI AND OVER NORTH PRINCE WILLIAM
SOUND WERE SLOWLY DIMINISHING THIS AFTERNOON. A WEAK LOW NEAR KODIAK
ISLAND BROUGHT AS LITTLE STRATUS OVER THE WESTERN GULF. BROAD AND
BRISK NE FLOW CAUSED BY THE PINCHED PRESSURE GRADIENT BETWEEN THE
EASTERN RUSSIA HIGH AND A PACIFIC LOW CONTINUED ACROSS MUCH OF THE
BERING SEA. A STRONG LOW CENTER SOUTH OF THE EASTERN ALEUTIANS WAS
STACKED UNDER A UPPER CENTER AND MOVING NE. THE ASSOCIATED WEATHER
FRONT WAS ELONGATING EAST/NE.

.MODEL DISCUSSION...
MODELS OVERALL DID A FAIR JOB INITIALIZING THE SYNOPTIC FIELDS.
FORECAST TRENDS ARE FAIRLY CLOSE BETWEEN AND GFS/ECMWF. THE ECMWF 12Z
RUN WAS A LITTLE FASTER AND BROUGHT IT MORE IN LINE WITH THE
CONSISTENTLY FASTER GFS RUN. SO OVERALL THE TIMING OF THE GFS/ECMWF
LOOK REASONABLE AS LOW AND FRONT HEAD TOWARD THE GULF.

.SHORT TERM FORECAST...

.SOUTHCENTRAL...
A 950S NORTH PACIFIC LOW HEADS TOWARD KODIAK TONIGHT AND ENDS UP OVER
THE BARREN ISLANDS TUE AS IT WEAKENS TO THE 970S. THE ASSOCIATED
FRONTAL TROUGH MOVES TO THE NORTH GULF MON AFTERNOON THEN INLAND AND
WEAKENS MON NIGHT AND TUE. SNOW SHOULD DEVELOP AROUND MIDNIGHT NEAR
KODIAK AND SPREAD TO THE KENAI PEN AND NORTH GULF MON MORNING/MON
AFTERNOON. SNOW SHOULD SHIFT OVER TO RAIN AT KODIAK MON MORNING THEN
BECOME MIXED OVER THE EASTERN KENAI AND PORTIONS OF THE NORTH GULF
MON AFTERNOON. SNOW WILL LIKELY BE HEAVY AT TIMES OVER THE EASTERN
KENAI MON...BECOMING MIXED WITH RAIN ALONG THE COASTS MON AFTERNOON.
SNOW WILL DIMINISH AT LOWER ELEVATIONS OF THE EASTERN KENAI MON NIGHT
AS TEMPS CONTINUE TO WARM AND SNOW MIXES WITH RAIN. SNOW WILL LIKELY
BE HEAVY AT TIMES IN THE VALDEZ AREA MON NIGHT...PROB EVEN MARGINAL
WINDS FOR BLIZZARD POTENTIAL FOR THOMPSON PASS. UPSLOPE CONDITIONS
OVER THE WESTERN SUSITNA VALLEY WILL PROVIDE OF SNOWS AROUND ADVISORY
LEVELS BEGINNING MON AFTERNOON AND CONTINUING THROUGH MONDAY NIGHT.
THE REMAINDER OF INLAND AREAS WILL GENERALLY BE INITIALLY DOWN-SLOPED
MON...BUT SNOW OR MIX SHOULD BECOME MORE WIDESPREAD TUE AS DOWN-SLOPE
WEAKENS.

STRONG WINDS WILL ACCOMPANY FRONT AND LOW WITH BARRIER JET
DEVELOPMENT AND RESULTANT STORMS IN ADVANCE OF THE FRONT ALONG THE
NORTH GULF MON AFTERNOON...THEN WEAKENING MON NIGHT. STORM FORCE NE
WINDS ARE ALSO LIKELY IN ADVANCE OF THE FRONT WEST OF THE BARREN
ISLANDS MON

SOUTHWEST ALASKA...
HIGH PRESSURE AND BRISK OFFSHORE FLOW CONTINUES TO DOMINATE OVER THE
SOUTHWEST MAINLAND THROUGH TONIGHT. AS THE LOW SOUTH OF THE
CENTRAL ALEUTIANS BEGINS TO TRACK TO THE NORTHEAST...AN ASSOCIATED
FRONTAL SYSTEM WILL BEGIN MOVE OVER THE AKPEN EARLY MONDAY MORNING.
THIS FRONTAL SYSTEM WILL PRODUCE GUSTY WINDS...ALONG WITH GENERALLY
LIGHT SNOW ACROSS THE SOUTHWEST MAINLAND INTO TUE. SNOW MAY BECOME
BRIEFLY MIXED OVER SOUTHERN BRISTOL BAY MON.

ALEUTIANS/AK PEPN/BERING SEA...BLOWING SNOW WILL BECOME A CONCERN
OVER THE BERING SEA SIDE OF THE AK PEN LATE TONIGHT AS THE FRONT
ASSOCIATED WITH THE NORTH PACIFIC LOW HEADS NORTH. TEMPS WILL LIKELY
BE A LITTLE TOO WARM AND LOW SNOW TOTALS PROBABLY SHOULD BE ENOUGH TO
KEEP CONDITIONS JUST ABOVE BLIZZARD. SO FOR NOW WILL CONVERT THE
BLIZZARD WATCH FOR THE AK PEN TO A BLOWING SNOW ADVISORY.
ELSEWHERE...BROAD NORTH TO NORTHEAST FLOW WILL CONTINUE ACROSS THE
BERING SEA INTO TUE.

.LONG TERM FORECAST...
A MORE ACTIVE PATTERN WILL COMMENCE WITH THE NORTH PACIFIC LOW MOVING
INTO THE WESTERN GULF OF ALASKA ON TUESDAY AND CONTINUE THROUGH THE
REMAINDER OF THE WEEK AS A SERIES OF LOWS FOLLOW CLOSELY ON THE HEELS
OF THE FIRST SYSTEM WHILE TAKING A VERY SIMILAR TRACK. THIS WILL
GENERALLY RESULT IN A MUCH WETTER PERIOD ACROSS THE SOUTHERN
MAINLAND...WITH STRONG WINDS AT TIMES AS VARIOUS ASSOCIATED FRONTS
ARRIVE ALONG THE NORTHERN GULF COAST. PRECIPITATION TYPE IS EXPECTED
TO REMAIN MOSTLY SNOW ALTHOUGH RAIN COULD MIX IN AT TIMES AS
TEMPERATURES TREND UPWARD...PARTICULARLY ALONG THE COAST.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...WINTER STORM WARNING 125
         SNOW ADVISORY 145
         BLOWING SNOW ADVISORY 181
MARINE...STORM WARNING 119 130
         GALE WARNING 120 125 131 132 138 139 150 155 160 165 170
                      172 174 179 180 181 351 352 412 414
         HEAVY FREEZING SPRAY WARNING 160 179 411 412 413 414
FIRE WEATHER...NONE

RMC MAR 14