Heavy Freezing Spray Warning 49, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
200 PM AKST SUN FEB 6 2011

.MODEL DISCUSSION...MODELS INITIALIZED WELL. SYNOPTIC SCALE FORECAST
TRENDS ARE IN GENERALLY GOOD AGREEMENT THROUGH THE SHORT TERM. THE
GFS/EC APPEAR TO BE HANDLING THE DEVELOPING LOW PRESSURE CENTER OVER
THE NORTH PACIFIC. THE NAM TENDS TO LAG BEHIND GFS/EC POSITIONS.

.UPPER LEVELS...THE PERSISTENT RIDGE OVER THE MAINLAND INTERIOR
SLOWLY MOVES EAST AS THE BROAD TROUGH OVER THE BERING SEA/ALEUTIANS
IS PUSHED NORTH BY BUILDING NORTH PACIFIC RIDGE. A LARGE LOW CENTER
OVER THE NORTH PACIFIC WEAKENS IT IT MOVES TO JUST SOUTH OF THE AK
PEN TUE MORNING. THIS CENTER FURTHER WEAKENS AND MOVES EAST ACROSS
THE MAINLAND AS A WAVE WED.

ANALYSIS...
A COMPACT LOW PRESSURE CENTER NEAR KODIAK ISLAND YESTERDAY AFTERNOON
WEAKENED AND MOVED INTO BRISTOL BAY OVERNIGHT. ITS ASSOCIATED FRONT
MOVED INTO BRISTOL BAY AND SATELLITE IMAGERY THIS MORNING SHOWS THE
WEAKENING FRONTAL BOUNDARY EXTENDING FROM SW ALASKA...THROUGH THE
KENAI PEN TO OVER THE SE GULF OF ALASKA. THE FRONT AND LOW CENTER
GENERALLY BROUGHT WIDESPREAD CLOUDS BUT LITTLE PRECIPITATION.
SATELLITE IMAGERY SHOWS SEVERAL SHORT WAVES WITH SHOWERS EXTENDING
FROM SOUTH OF THE ALEUTIANS TO OVER THE WESTERN GULF THIS MORNING.
THE LOW COMPLEX OVER THE BERING SEA/EAST ALEUTIANS IS SLOWLY
WEAKENING AND DRIFTING NORTH. HIGH PRESSURE CONTINUES IT HOLD OVER
THE INTERIOR MAINLAND CREATING RELATIVELY STRONG TEMPERATURE
INVERSIONS THIS MORNING...WHICH RESULTED IN WIDESPREAD LOW CLOUDS AND
PATCHY FOG OVER THE COPPER RIVER BASIN.

.SHORT TERM...GENERALLY WINDY...WET...AND WARMER WEATHER ON THE WAY
FOR MUCH OF THE MAINLAND.
THE WEAKENING FRONTAL ZONE EXTENDING ACROSS SOUTHCENTRAL WILL SHEAR
APART OVER THE NEXT 24 HRS OR SO. A LARGE LOW PRESSURE CENTER OVER
THE NORTH PACIFIC WEAKENS AS IT MOVES TO NEAR CHIGNIK TUE AFTERNOON.
THIS CENTER CONTINUES TO WEAKEN AS IT MOVES INTO THE WESTERN INTERIOR
WED. THE ASSOCIATED FRONTAL TROUGH BRINGS MOISTURE TO THE AK
PEN/EASTERN ALEUTIANS MON. MOISTURE SPREADS TO THE EASTERN BERING/SW
MAINLAND...AND SOUTHCENTRAL MON NIGHT AND TUE. MOST AREAS WILL SEE
RISING TEMPS WITH WARM ADVECTION AHEAD OF AND WITH THE APPROACHING
FRONTAL TROUGH. PRECIPITATION LIKELY WILL BE RAIN OR A MIX ALONG THE
GULF COAST AND MIXED PRECIPITATION OVER BRISTOL BAY....THOUGH SOME
LOCATIONS WITH TRAPPED COLD AIR MAY SEE A CHANCE OF LIGHT FREEZING
RAIN. COOLER AIR WILL PROGRESS EAST ACROSS THE EAST ALEUTIANS/EASTERN
BERING SEA AS THE LOW CENTER MOVES INTO THE SW INTERIOR EARLY WED.
PRESSURE GRADIENTS WILL INCREASE WITH THE APPROACH OF THE LOW
PRESSURE/FRONT AND BRING VERY WINDY CONDITIONS TO THE AK PEN AND
EAST/CENTRAL ALEUTIANS/WESTERN GULF MON EVENING. GRADIENTS TIGHTEN
ACROSS SOUTHCENTRAL AND THE REMAINDER OF THE GULF TUE.

.SOUTHCENTRAL ALASKA...
RIDGING OVER THE COPPER RIVER WILL HOLD THROUGH MON NIGHT...SO EXPECT
LOW COLDS AND FOG TO CONTINUE INTO TUE MORNING. MIXING OF THE AIR
WITH INCREASING PRESSURE GRADIENTS WILL TEND TO BREAK UP LOW
CONDITIONS OVER THE COPPER RIVER BASIN TUE AFTERNOON. SOME ISOLATED
SNOW SHOWERS ARE POSSIBLE OVER PORTIONS OF SOUTHCENTRAL ALASKA
THROUGH MON AS WEAK UPPER SHORT WAVES LIFT NORTH AND EAST.
WARM...WINDY...AND WET WEATHER CAN BE EXPECTED ON TUE AND WED.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...GALE 130 132 138 150 155 160 165 170 172.
FIRE WEATHER...NONE.

RMC FEB 11