Brisk Wind Advisory 16, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
515 PM AKST TUE FEB 12 2013

.ANALYSIS AND UPPER LEVELS...
AN UPPER LEVEL LOW REMAINS OVER THE NORTHERN BERING...AND IS SLOWLY
MOVING EAST TOWARDS THE WEST COAST. BELOW THIS A SURFACE LOW IS JUST
OFF THE WEST COAST...BRINGING SNOW SHOWERS TO THE SOUTHWEST MAINLAND.
SOUTH OF THE ALEUTIAN CHAIN...A DEVELOPING LOW IS APPROACHING KODIAK
ISLAND. THIS LOW WILL CONTINUE DEVELOPING TODAY...AND BE THE NEXT
WEATHER MAKER FOR THE GULF COAST AND SOUTHCENTRAL STARTING THIS
EVENING. YET ANOTHER DEVELOPING LOW IS CURRENTLY WELL SOUTH OF THE
ALEUTIANS AND IS MOVING TO THE NORTHEAST. THIS SYSTEM WILL BEGIN
AFFECTING THE EASTERN ALEUTIANS ON WEDNESDAY MORNING.

.MODEL DISCUSSION...
THE MODELS ARE IN AGREEMENT WITH REGARDS TO THE TIMING OF THE
DEVELOPING SURFACE LOW CURRENTLY NEAR KODIAK ISLAND THROUGH TOMORROW
MORNING. DIFFERENCES DO EXIST WITH REGARDS TO THE TIMING OF THE
PRECIPITATION INTO SOUTHCENTRAL IN THE NEAR TERM. THE LOCAL WRF IS
CERTAINLY THE MOST AGGRESSIVE WITH BRINGING THE SNOW INTO THE
ANCHORAGE BOWL AND MAT VALLEY THIS MORNING...HOWEVER THE SNOW IS
CURRENTLY MAINLY OVER COOK INLET WITH ONLY WEAK SNOW SHOWERS PASSING
OVER TOWN SO THIS MAY BE A LITTLE OVERDONE. THE MODELS (EXCEPT FOR
THE GFS) ARE THEN IN MUCH BETTER AGREEMENT WITH THE TIMING OF THE
NEXT WAVE OF SNOW FOR THIS EVENING AND OVERNIGHT TONIGHT.

THE MODELS ARE IN GOOD AGREEMENT THE LOCATION OF THE NEXT ALEUTIAN
LOW THROUGH WEDNESDAY EVENING...BUT STILL HAVE DIFFERENCES WITH ITS
INTENSITY. THE MORNING PACKAGE MOSTLY USED THE GFS SOLUTION FOR THIS
LOW WHICH IS SLIGHTLY DEEPER THAN THE NAM/EC THROUGHOUT THE EVENT.

.SHORT TERM FORECAST...
.SOUTHCENTRAL...THE MAIN CONCERN IN THE NEAR TERM IS WITH THE SNOW
CURRENTLY MOVING UP COOK INLET. WIDESPREAD SNOW IS CURRENTLY MOVING
UP COOK INLET...WITH ONLY SCATTERED SHOWERS MAKING IT FAR ENOUGH EAST
TO IMPACT THE POPULATION CENTERS. THIS WILL MOST LIKELY BE THE CASE
FOR THE REST OF TODAY...AS WEAK DOWN SLOPING SHOULD PREVENT ANY
SIGNIFICANT SNOW BANDS TO DEVELOP OVER ANCHORAGE. THE NEXT WAVE OF
SNOW WILL QUICKLY FOLLOW THE CURRENT ONE AS ACCUMULATING SNOWFALL  IS
ONCE AGAIN EXPECTED STARTING LATE TONIGHT. THIS SNOWFALL WILL BE
PRODUCED DUE TO A WEAK SURFACE LOW THAT WILL MOVE INTO THE GULF THIS
EVENING...THEN DISSIPATE NEAR PRINCE WILLIAM SOUND TOMORROW MORNING.
THIS SYSTEM WILL ALSO KEEP MOST OF THE COASTAL AREAS IN THE RAIN AND
SNOW THROUGH TOMORROW MORNING.

.SOUTHWEST...WEAK LOWS IN THE EASTERN ALEUTIANS AND NEAR KODIAK
ISLAND WILL CONTINUE TO PRODUCE SCATTERED SNOW SHOWERS THROUGH THIS
EVENING. THE ALEUTIAN LOW WILL THEN QUICKLY FOLLOW THE DEPARTING
LOWS...AND WILL BRING THE NEXT CHANCE OF SNOW TO THE AREA BEGINNING
TOMORROW AFTERNOON.

.BERING SEA AND ALEUTIANS...WITH THE EXCEPTION OF SNOW FOR THE
PRIBILOFS...QUIET WEATHER WILL REMAIN OVER THE BERING SEA UNTIL
TOMORROW MORNING...WHEN THE ALEUTIAN LOW WILL BEGIN IMPACTING THE
AREA WITH SNOW AND GALE FORCE WINDS.

.LONG TERM FORECAST...
THE ALEUTIAN LOW TRACK THAT IS SETTING UP FOR THE SHORT TERM WILL
CONTINUE THROUGH THE WEEKEND. THIS PATTERN WILL BRING A SERIES OF
EASTERLY MOVING ALEUTIAN LOWS INTO THE GULF...WITH RELATIVELY SHORT
BREAKS IN BETWEEN LOWS. IT DOES APPEAR THAT THIS SETUP WILL BREAK
DOWN EARLY NEXT WEEK HOWEVER...AS THERE IS GOOD MODEL AGREEMENT THAT
A STRENGTHENING SIBERIAN RIDGE WILL MOVE IN THE
ALEUTIANS...PREVENTING THE EASTWARD PROGRESSION OF FURTHER LOWS.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...GALE 132 170 172 175 352
         HEAVY FREEZING SPRAY 179 411 412
FIRE WEATHER...NONE

DEK FEB 13