Small Craft Advisory 1053, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
200 PM AST THU DEC 15 2005

.DISCUSSION...

PERSISTENT UPPER LEVEL RIDGE OVER THE CONTINENTAL WEST COAST AND
ALASKA RANGE THIS AFTERNOON...WITH A LARGE LOW OVER THE BERING AND A
TROUGH AXIS EXTENDING ACROSS THE AKPEN INTO THE GULF. AT THE
SURFACE...LOWS ARE NEAR SITKINAK AND SHEMYA.

MODELS ARE IN GOOD AGREEMENT FOR TWO DAYS BEFORE DIVERGING IN THEIR
SOLUTIONS. SINCE MOST OF THE DIFFERENCES ARE WELL SOUTH OF THE
GULF...THE NAM WAS USED FOR EARLY PERIODS AND THE GFS WAS USED FOR
THE REMAINDER OF THE FORECAST.

IN THE EAST...THE MAIN PLAYER TONIGHT IS THE SITKINAK LOW AS IT
CROSSES THE AKPEN INTO WESTERN ALASKA TONIGHT AND TOMORROW. IT WILL
INDUCE WARNING LEVEL WINDS ACROSS WESTERN TURNAGAIN ARM AND THE
ANCHORAGE HILLSIDE...MAINLY THROUGH THE EARLY EVENING BUT POSSIBLY
INTO THE EARLY MORNING HOURS. PRECIPITATION WILL BE PRIMARILY RAIN IN
FAVORED UPSLOPE REGIONS ALONG THE COAST AS DOWNSLOPING MINIMIZES
PRECIP IN THE ANCHORAGE BOWL. DESPITE THE WARM ADVECTION...SNOWFALL
SHOULD STILL AFFECT HIGHER ELEVATION OF THE ALASKA RANGE AND
TALKEETNA MOUNTAINS WEST OF SKWENTNA AND NORTH OF TALKEETNA.

IN THE SHORT TERM...WARM AIR OVERRUNNING ENTRENCHED COLD AIR WITH
SOME FREEZING RAIN WILL AFFECT WESTERN PORTIONS OF THE KUSKOKWIM
VALLEY AND EASTERN PORTIONS OF THE COPPER RIVER BASIN TONIGHT.

AS THE SITKINAK LOW PROGRESSES TOWARD THE BERING STRAIT...A TRAILING
OCCLUDED FRONT WILL SWEEP ACROSS THE GULF ON FRI..BRINGING THE LAST
SURGE OF RAIN TO THE COAST. RIDGE BUILDING IN THE GULF WILL BRING DRY
CONDITIONS TO AREAS SOUTH AND EAST OF THE ALASKA RANGE FOR THE
WEEKEND.

IN THE WEST...AS THE SITKINAK LOW MOVES NORTH IT WILL BRING COLDER
AIR ALOFT INTO SOUTHWESTERN ALASKA ON FRIDAY...ENDING ANY LINGERING
FREEZING RAIN. SOUTHWEST FLOW THAT SETS UP SHOULD BRING SNOW THAT
CUTS OFF FRI NIGHT INTO SAT. THE SECOND HALF OF THE WEEKEND SHOULD BE
DRY.

THE BERING LOW WILL MOVE SOUTH OF THE ALEUTIANS BY FRI NIGHT WITH
RAIN AND SNOW SHOWERS OVER MUCH OF THE AREA. LIGHT TO MODERATE WINDS
OVER THE BERING WILL BECOME NORTHEAST DURING THIS PERIOD. THE NEXT
NORTH PACIFIC LOW ARRIVES SAT AND BRINGS AT LEAST GALE FORCE WINDS TO
THE CENTRAL ALEUTIANS FOR THE WEEKEND...ALONG WITH RAIN.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...HIGH WIND WARNING 101
MARINE...HEAVY FREEZING SPRAY 185
         GALES 120 125 130 132 138 140 185
FIRE WEATHER...NONE

DS DEC 05