Dense Fog Advisory 2, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
100 PM AKDT WED AUG 8 2012

.MODEL DISCUSSION...MODELS IN REASONABLE AGREEMENT ON SURFACE
SOLUTIONS IN THE SHORT-TERM.  IN THE GULF GFS RUNS 3 TO 5 MB DEEPER
THAN NAM BUT BOTH MODELS SHOW SIMILAR PRESSURE GRADIENTS. EAST
FORECASTER LEANING TOWARDS GFS SOLUTION.  IN THE WEST THERE THE MODEL
SOLUTIONS ARE MORE DIVERGENT ON FRI ONWARDS.  THE GENERAL SOLUTION IS

FOR THE HIGH PRESSURE CURRENTLY OVER THE CENTRAL AND EASTERN BERING
TO DISSIPATE ALLOWING A SIBERIAN LOW TO MOVE INTO THE CENTRAL BERING
THU NIGHT. THE RESULT IS AN ELONGATED N-S TROUGH OVER THE CENTRAL
BERING EXTENDING WELL SOUTH OF THE CENTRAL AL.  THE GFS DOES GENERATE
STRONGER WINDS WITH THIS SYSTEM BY ABOUT 10 KTS.  THE WEST FORECAST
WILL REFLECT MORE GFS THAN NAM IN NEW PACKAGE.

.ANALYSIS AND UPPER LEVELS...CURRENTLY GULF LOW MOVES A LITTLE
FURTHER WEST THIS EVENING AND THEN DISSIPATES OVER NIGHT.  SHOWERS
AND CLOUDS MOVED A LITTLE FURTHER INLAND AND WEST FROM WHAT WE
EXPECTED YESTERDAY BUT SHOULD WEAKEN OVER NIGHT.  HIGH PRESSURE IN
THE CENTRAL BERING HOLDS FOR ANOTHER 30 HOURS BEFORE GIVING WAY TO
SYSTEM FROM THE NORTHWEST.

.SHORT TERM FORECAST...
BERING REGION...CONTINUED STRATUS AND FOG THROUGH FRI MORNING EAST OF
THE LINE ALONG 175W. SHOWERS MOVING INTO THE WESTERN PORTION OF THE
CENTRAL AL THIS AFTERNOON WEAKENING THU. FRONT ASSOCIATED WITH THIS
SYSTEM INTENSIFYING ON FRI AFTERNOON OVER CENTRAL AND EASTERN AL.

SOUTHWEST...AREA IS UNDER INFLUENCE OF HIGH PRESSURE...LITTLE ACTIVE
WEATHER WITH EXCEPTION OF STRATUS AND FOG IN VALLEYS AND ALONG THE
COAST.

SOUTHCENTRAL...RAIN AND SHOWERS ALONG THE NORTHERN GULF COAST
CONTINUING THIS EVENING...GENERALLY CLOUDY INLAND WITH STRATUS ACROSS
MUCH OF COOK INLET TONIGHT.  EXPECTING GENERALLY SUNNY CONDITIONS
INLAND THU AND FRI WITH AREAS OF STRATUS ALONG THE COAST INCLUDING
COOK INLET.

.LONG TERM FORECAST...BY SAT NIGHT BERING LOW IS EXPECTED TO MOVE
INTO THE CENTRAL AL AND CONTINUE INTO THE NORTH PACIFIC.  MOST OF THE
SHOWERS SHOULD BE IN THE EASTERN AL AND SOUTHERN AK PEN SAT NIGHT
THROUGH SUN. WEAK GULF ON SAT LOW SHOULD HAVE LITTLE IMPACT ON
WEATHER OVER MAINLAND AND DISSIPATES ON SUN.  THERMAL TROUGH DOES
APPEAR TO FORM OVER AK RANGE ON THE WEEKEND AND EARLY NEXT WEEK SO
POTENTIAL FOR AFTERNOON AND EVENING CONVECTION OVER SUSITNA AND
COPPER BASINS.

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

JMP AUG 12