Small Craft Advisory 545, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
200 PM AKDT SUN JUL 12 2009

.ANALYSIS AND UPPER LEVELS...
ALOFT...UPPER LEVEL RIDGE CENTERED OVER THE ALASKA MAINLAND THIS
AFTERNOON WITH AN UPPER LOW OVER THE NORTHWESTERN BERING. THIS
PATTERN WILL SLOWLY TRANSLATE EAST OVER THE NEXT SEVERAL DAYS.

AT THE SURFACE...THE THERMAL TROUGH REMAINS CENTERED ALONG THE ALASKA
RANGE. A LOW IS EVIDENT ON SATELLITE IMAGERY NORTH OF SHEMYA...WITH
AN ASSOCIATED FRONT DRAPED ACROSS THE CENTRAL BERING AND ALEUTIANS.
ELSEWHERE...HIGH PRESSURE PERSISTS ACROSS THE GULF OF ALASKA.

.MODEL DISCUSSION...
MODELS REMAIN IN GOOD AGREEMENT INTO THE UPCOMING WORK WEEK.
SOLUTIONS AGREE ON TAKING THE LOW NEAR SHEMYA INTO EASTERN RUSSIA
WHILE DISSIPATING...WITH THE ASSOCIATED FRONT WASHING OUT OVER THE
AKPEN AND SOUTHWESTERN MAINLAND ON TUESDAY. AFTERWARD...ANOTHER LOW
IS EXPECTED TO APPROACH THE WESTERN ISLANDS BY MIDWEEK. FARTHER
EAST...HIGH PRESSURE WILL REMAIN IN CONTROL THROUGH AT LEAST THE
MIDDLE OF THIS WEEK. LITTLE CHANGE WAS MADE TO THE EXISTING
FORECAST...WITH A FOCUS ON THE NAM AND GFS IN THE SHORT TERM.

.SHORT TERM FORECAST...
.SOUTHCENTRAL...
GENERALLY QUIET WEATHER WILL CONTINUE OVER THE NEXT SEVERAL DAYS AS
THE UPPER RIDGE REMAINS IN CONTROL. AS A RESULT...AFTERNOON
CONVECTION SHOULD BE MINIMAL OVER THE NEXT COUPLE OF AFTERNOONS WITH
THE BEST SHOT FOR ANY SHOWERS OCCURRING ALONG THE ALASKA RANGE.
OTHERWISE...NIGHTTIME AND EARLY MORNING FOG AND LOW CLOUDS WILL
IMPACT COASTAL AREAS AS THE MARINE LAYER PENETRATES INLAND OVERNIGHT.
HAZE AND SMOKE WILL CONTINUE TO HINDER VISIBILITIES ALTHOUGH
CONDITIONS WILL BE GRADUALLY IMPROVING OVER THE NEXT SEVERAL DAYS.

.SOUTHWEST...
GENERALLY QUIET WEATHER TODAY EXCEPT FOR ISOLATED SHOWERS AND
THUNDERSTORMS ALONG THE MOUNTAINS THIS AFTERNOON AND EVENING. CLOUDS
AND PRECIP WILL BE ON THE INCREASE MONDAY AND TUESDAY AS THE FRONT
OVER THE BERING MOVES INTO THE REGION AND DISSIPATES.

.BERING SEA AND ALEUTIANS...
RAIN AND GALE FORCE WINDS WILL CONTINUE TO IMPACT THE ISLANDS THROUGH
TONIGHT AS THE LOW AND ASSOCIATED FRONT MOVE ACROSS THE AREA. SHOWERS
WILL PERSIST MONDAY AND TUESDAY...BEFORE PRECIP BECOMES MORE
WIDESPREAD ONCE AGAIN TUESDAY NIGHT AND WEDNESDAY AS ANOTHER LOW
MOVES INTO THE BERING.

.LONG TERM FORECAST...
A BREAKDOWN OF THE CURRENT PATTERN STILL APPEARS LIKELY...WITH A
RETURN TO MORE SEASONABLE WEATHER OVER THE SOUTHERN MAINLAND BY LATE
WEEK. THE BERING AND ALEUTIANS WILL SEE PERIODS OF UNSETTLED
WEATHER...WITH MOIST SOUTHERLY FLOW SETTING UP OVER SOUTHWEST AK.
HIGH PRESSURE RIDGING OVER SOUTHCENTRAL WILL KEEP MOST SHOWER
ACTIVITY SUPPRESSED...ALTHOUGH MOISTURE WILL STILL BE ON THE
INCREASE.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...GALE 179 185
FIRE WEATHER...NONE

NRH JUL 09