Blizzard Watch 9, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
200 PM AKST TUE MAR 2 2010

.MODEL DISCUSSION...MODEL MSLP INITIALIZATIONS ARE IN GOOD. FORECAST
TREND WITH CURRENT GULF COMPLEX AND CENTER MOVING ACROSS THE
ALEUTIANS ARE SIMILAR AND REASONABLE. MODELS HAVE SHOW SIGNIFICANT
CHANGE IN TIMING OF NEXT STORM CENTER TO IMPACT THE ALEUTIANS. NEW
TREND MOVES CENTER ABOUT 6 HRS AHEAD OF PREVIOUS FORECASTS. WILL
TREND FORECASTS TOWARD FASTER SPEED OF MOVEMENT...BUT NOT GO FULLY
WITH NEW SOLUTIONS UNTIL WE GET A LOOK AT THE NEXT MODEL CYCLE.
APPEARS THAT THE GFS PRESSURES ON THIS CENTER ARE TOO LOW. ENSEMBLE
FORECAST SHOWS SEVERAL MEMBERS WITH PRESSURE MUCH HIGHER THAN THE
OPERATIONAL RUN. SO WILL BUMP UP PRESSURES SOME ON THE GFS...BUT NOT
AS HIGH AS THE EUROPEAN MODELS. MODELS WILL LIKELY CONTINUE TO MAKE
TIMING AND INTENSITY ADJUSTMENTS BEFORE SETTLING DOWN.

.ANALYSIS AND UPPER LEVELS...
.500 MB...WEAK TROUGH OVER THE GULF LIFTS NORTH AS WEAKENING LOW
CENTER OVER THE EASTERN BERING SEA SHIFTS EAST AND BROADENS. THIS
CENTER WILL SPREAD COOLER TEMPERATURES ALOFT OVER MUCH OF THE GULF
AND SOUTHERN MAINLAND WED. SHORT WAVE MOVING OFF JAPAN INTENSIFIES AS
MOVES ACROSS THE NORTH PACIFIC AS COLD AIR SURGES SOUTH FROM THE
KAMCHATKA PEN/WESTERN BERING SEA. CENTER DEVELOPS AND INTENSIFIES AS
IT MOVES TOWARD BRISTOL BAY FRI AFTERNOON. RIDGE IN ADVANCE OF THIS
CENTER AMPLIFIES AND SPREADS WARMER AIR ALOFT TO THE AK PEN/SW AK THU
AND THE GULF/SOUTHCENTRAL FRI.

.SURFACE FEATURES...
WEAKENING LOW OVER THE GULF MOVES DRIFTS NORTH AND DISSIPATES
TONIGHT. TROUGH EXTENDING SE ACROSS THE GULF OF ALASKA MOVES TO THE
NORTH GULF COAST BY THIS EVENING THEN WEAKENS INLAND TONIGHT. STORM
CENTER OVER THE EASTERN ALEUTIANS MOVES SOUTH OF THE KENAI PEN WED
AFTERNOON AND THEN MOVES INTO WESTERN PRINCE WILLIAM SOUND THU.
ASSOCIATED FRONTAL TROUGH EXTENDING ACROSS THE EASTERN BERING
SEA...SW AK...AND KODIAK ISLAND MOVES NORTH AND EAST. TRIPLE POINT
FEATURE DEVELOPS ALONG THE FRONT NEAR KODIAK THIS EVENING THEN MOVES
TO SOUTHERN COOK INLET WED MORNING. TRAILING FRONT ELONGATES SE AND
MOVES TO THE NORTHERN GULF COAST EARLY WED MORNING THEN INLAND WED
AFTERNOON.

DEVELOPING STORM CENTER OVER THE NORTH PACIFIC INTENSIFIES AND MOVES
TO THE CENTRAL ALEUTIANS WITH A PRESSURE IN THE LOWER 950S THU
AFTERNOON. AS MENTIONED ABOVE THERE HAS BEEN A SIGNIFICANT SPEEDING
UP OF THIS CENTER ON THE 12Z MODEL RUNS. CENTER MOVES TO INTO BRISTOL
BAY IN THE 950S FRI AFTERNOON. ASSOCIATED OCCLUDED FRONT MOVES TO THE
WESTERN/CENTRAL ALEUTIANS LATE WED NIGHT THEN TO THE PRIBILOFS AND
WESTERN AK PEN THU AFTERNOON. FRONT CONTINUES TO SW ALASKA/WESTERN
GULF THU.

.SHORT TERM FORECAST...
.SOUTHCENTRAL...STRONG WINDS ARE EXPECTED TO CONTINUE ALONG THE
NORTHERN GULF TONIGHT AS FRONT MOVES NORTH. PRESSURE GRADIENTS WILL
CONTINUE STRONG ACROSS SOUTHCENTRAL TONIGHT...SO GAP WINDS CAN BE
EXPECTED ACROSS THE KENAI PEN/ANCHORAGE BOWL/MAT VALLEY. GRADIENTS
DIMINISH WED. STRONG SE FLOW IN THE LOW/MID LEVELS TONIGHT LIKELY TO
KEEP MAJORITY OF PRECIPITATION ALONG THE GULF AND SE EXPOSURES OF
SOUTHCENTRAL AS DOWN-SLOPING TONIGHT WILL MINIMIZE PRECIPITATION
INLAND. MAY SEE A LITTLE MORE SNOW SHOWERS INLAND AREAS WED WITH
RELAXING GRADIENTS AND WITH WEAKENING FRONT MOVING INLAND. PROMISING
SNOWFALL POTENTIAL TO SOUTHCENTRAL AS WEAKENING STORM FROM THE
ALEUTIANS HEADS TOWARD PRINCE WILLIAM SOUND THU AND COLD AIR SPREADS
ACROSS THE WESTERN GULF/KENAI PEN.

.WEST...STRONGEST WINDS ARE ON THE ON SOUTH AND WEST QUADS OF STORM
CURRENTLY OVER THE EASTERN ALEUTIANS. STRONG WINDS WITH SOME BLOWING
SNOW LIKELY OF THE EAST ALEUTIANS/AK PEN TONIGHT. BLIZZARD CONDITIONS
WILL MAY LAST INTO THE EVENING HOURS OVER THE PRIBILOFS AS SNOW
BLOWING OFF THE ICE PACK MAY PROLONG CONDITIONS AFTER FRONT MOVES BY.
NEXT STORM APPROACHING TO ALEUTIANS STILL HAS TIMING ISSUES SO WILL
WAIT ANOTHER RUN BEFORE ISSUING NECESSARY WATCHES WHICH WITH CURRENT
FORECAST MOVEMENT WOULD SUGGEST. FOR NOW STILL LOOKS LIKE VERY STRONG
WINDS TO THE ALEUTIANS WITH BLOWING SNOW CONCERNS ON THE BACKSIDE OF
CENTER. WARM ADVECTION EAST OF CENTER WILL BE FAIRLY PRONOUNCED SO
BLIZZARD CONDITIONS ARE NOT MUCH OF A CONCERN FOR THE AK PEN/EAST
ALEUTIANS EARLY ON. HOWEVER...MAY SEE ANOTHER ROUND OF BLIZZARDS FOR
THE PRIBILOFS LATE THU AFTERNOON AND INTO SW AK COAST THU NIGHT.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...BLIZZARD WARNING 191.
MARINE...GALE 120 125 129 130 132 155 165 170 171.
         STORM 172 175 176
MARINE...
FIRE WEATHER...NONE.

RMC MAR 10