Blizzard in Alaska, March 28 to 29, 2008

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
200 PM ADT FRI MAR 28 2008

.MODEL DISCUSSION...MODEL INITIALIZATIONS REASONABLE. FORECAST TRENDS
IN GOOD AGREEMENT AND ALSO REASONABLE. MORNING PACKAGE WAS BASED ON
THE 00Z GFS MODEL. AFTERNOON PACKAGE WILL TREND TOWARD THE 12Z GFS
THROUGH 60 HOURS...WITH LITTLE CHANGE BEYOND.

.UPPER LEVELS...
WEAK TROUGH OVER SOUTHCENTRAL MOVES INTO WESTERN CANADA TONIGHT.
RIDGE BUILDS OVER SOUTHCENTRAL AND THE GULF OF ALASKA TONIGHT. TROUGH
OVER OVER BERING SEA WEAKENS AS IT MOVES SLOWLY EAST. GENERAL
SOUTHWESTERLY FLOW WILL SET UP OVER WESTERN ALASKA TONIGHT AND SPREAD
EAST THROUGH THE WEEKEND. LOW CENTER SOUTH OF THE CENTRAL ALEUTIANS
MOVES SOUTH OF THE ALASKA PENINSULA SAT NIGHT AND WEAKENS. NEXT
DEVELOPING LOW CENTER INTENSIFIES AS IT MOVES TO NEAR THE WESTERN
ALEUTIANS SUN.

.SHORT TERM FORECAST...SWITCH TO A PROGRESSIVE UPPER FLOW PATTERN
WILL BRING UNSETTLED WEATHER TO MUCH OF ALASKA THROUGH EARLY NEXT
WEEK.

EAST...SNOW SHOWERS LIKELY TO CONTINUE OVER THE GULF OF ALASKA UNTIL
PASSAGE OF UPPER TROUGH TONIGHT. PROBABLY WILL SEE PATCHY FOG ACROSS
SOUTHCENTRAL TONIGHT WITH SUBSIDENCE IN ADVANCE OF UPPER RIDGE. WEAK
FRONTAL TROUGH SPREADS SNOW TO THE WESTERN GULF SAT MORNING. SOUTHERN
END OF THE FRONTAL TROUGH WILL SLOW AND WEAKEN. SW FLOW ALOFT WILL
ELONGATE FRONT NORTH INTO THE INTERIOR. MAY SEE A FAIR AMOUNT OF SNOW
INTO THE SUSITNA VALLEY WITH ONSET OF SW FLOW IN THE MID-LEVELS SAT
NIGHT AND SUNDAY. EXPECT WILL SNOW OR MIXED OVER
SOUTHCENTRAL/NORTHERN GULF THROUGH THE WEEKEND WITH SW FLOW ALOFT.
EAST-WEST PRESSURE GRADIENTS BUILD ACROSS SOUTHCENTRAL ALASKA SAT
WITH APPROACH OF WEAKENING FRONT. GRADIENTS WILL INCREASE FURTHER SAT
SAT NIGHT/SUN AS LOW CENTER MOVES INTO BRISTOL BAY. PRESSURE GRADIENT
MAY SLACKEN SOME SUN NIGHT BEFORE TIGHTENING AGAIN MON WITH APPROACH
OF YET ANOTHER LOW CENTER. SO...WINDY CONDITIONS LIKELY TO DEVELOP
OVER SOUTHCENTRAL SAT AND CONTINUE INTO EARLY NEXT WEEK.

.WEST...FRONTAL TROUGH APPROACHING THE PRIBILOFS ISLANDS IS PRODUCING
NEAR BLIZZARD CONDITIONS AS OF EARLY THIS AFTERNOON. EXPECT FRONT
SHOULD PUSH EAST THROUGH THIS EVENING AND TEMPS WITH WARM AND WINDS
SUBSIDE. MAY SEE BLIZZARD CONDITIONS DEVELOP ALONG THE DELTA COAST
AFTER MIDNIGHT TONIGHT WITH APPROACH OF FRONTAL TROUGH. FRONT LIKELY
TO BRING A COUPLE INCHES OF SNOWS AND GUSTY SOUTHEAST. IF CONDITIONS
DEVELOP...THEN THEY SHOULD SUBSIDE IN THE AFTERNOON AS FRONT MOVES
INLAND AND COASTAL WINDS DIMINISH. DEVELOPING 980S LOW CENTER MOVES
TO NEAR DUTCH HARBOR SAT EVENING AND WEAKENS AS IT MOVES INTO BRISTOL
BAY EARLY SUN. NEXT IN A SERIES OF CENTERS MOVES TO THE WESTERN
ALEUTIANS IN THE MID 980S SUN EVENING. THIS CENTER CONTINUES TO
INTENSIFY AS IT MOVES TO BRISTOL BAY MON EVENING. TEMPS IN GENERAL
WILL WARM OVER MUCH OF THE BERING SEA/SW ALASKA OVER THE NEXT COUPLE
OF DAYS.

.LONG TERM FORECAST...UNSETTLED WEATHER WILL CONTINUE OVER THE
MAINLAND THROUGH MID-NEXT WEEK AS UPPER TROUGH MOVES OVER THE WESTERN
AND CENTRAL MAINLAND. HIGH PRESSURE BUILDS OVER THE CENTRAL AND
EASTERN BERING SEA BY MIDWEEK..SO WILL SEE A MOVE BACK TOWARD MORE
STABLE CONDITIONS.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...BLIZZARD WARNING ZONE 195. BLIZZARD WATCH ZONE 155.
MARINE...GALE 130.
FIRE WEATHER...NONE.

RMC MAR 08