Blizzard in Alaska, December 30, 2007

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 AM AST SUN DEC 30 2007

.MODEL DISCUSSION...
FAIRLY GOOD CONSISTENCY AND AGREEMENT AMONGST THE MAJOR MODELS. GFS
MAINLY PREFERRED...WITH NAM FOR DETAILS ON AND/OR NEAR LAND.

.ANALYSIS AND UPPER LEVELS...
UPPER LOW SOUTH OF THE PENINSULA WITH A RIDGE BUILDING OVER THE GULF
OF ALASKA. MAIN (SUBTROPICAL) JET TRANSITIONING FROM ZONAL TO HIGHER
AMPLITUDE OVER THE NORTHERN PACIFIC. WEAKER LOWS OVER THE BERING
STRAIT AND THE YUKON AND A WEAK HIGH OVER EASTERN ALASKA ASSOCIATED
WITH THE (NOT SURPRISINGLY WEAKER) ARCTIC JET.

.SHORT TERM FORECAST...
LOW SOUTH OF THE PENINSULA CURRENTLY PRODUCING BLIZZARD CONDITIONS
AS ARCTIC AIR FROM SIBERIA WRAPS INTO THE SYSTEM. THIS LOW IS
SHARPENING AND BEGINNING TO TAP SUBTROPICAL AIR. AS THE WARM MOIST
AIR MEETS THE ARCTIC AIR TONIGHT AND MONDAY...A LOW WILL BOMB OUT
IN THE CENTRAL GULF. STORM FORCE WINDS WILL MOVE THROUGH THE
NORTHERN GULF BUT WEAKEN WHEN THEY APPROACH THE COAST ON TUESDAY AS
THE LOW STALLS AND BEGINS TO FILL. RIDGING TO THE NORTH OF THIS LOW
WILL PUSH INTO SOUTHERN ALASKA MONDAY NIGHT THROUGH TUESDAY.

.LONG TERM FORECAST...
THE SOUTHERN ALASKA RIDGE WILL WEAKEN BY LATER IN THE WEEK AS THE
LOW RESPONSIBLE FOR IT WEAKENS AND DRIFTS EAST. SEASONABLE
TEMPERATURES AND PRECIPITATION WILL BE THE RESULT OVER SOUTH CENTRAL
AND SOUTHWEST ALASKA. MODELS BEGIN TO DIVERGE BY THE WEEKEND...BUT
IT LOOKS LIKE THE MEAN UPPER LEVEL TROUGH POSITION WILL STRENGTHEN
OVER THE STATE...LEADING TO A COOLING TREND.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...BLIZZARD WARNING 181 185.
MARINE...STORM WARNING 175 176.
         GALE WARNING 120 130 132 138 150 155 160 165 170 171 172.
         HVY FRZ SPRAY 121 129 130 140 155 160 165 180 185.
FIRE WEATHER...NONE.

LUDWIG DEC 07