Small Craft Advisory 584, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
100 PM AKDT FRI AUG 19 2011

.MODEL DISCUSSION...NAM AS WELL AS GFS AND EC IN REASONABLE AGREEMENT
IN SYNOPTIC FEATURES OVER THE NEXT SEVERAL DAYS.  MAIN PATTERN IS A
PARENT LOW IN THE CENTRAL BERING WITH A DEVELOPING LOW TODAY OVER
KODIAK ISLAND.  THE SURFACE LOW MOVES OVER NORTHERN KODIAK ISLAND
THIS EVENING AND INTO SOUTHERN COOK INLET BEFORE MOVING ONSHORE IN
KAMISHAK BAY. THE UPPER LOW CENTER MOVES OVER THE NORTHERN GULF SAT
EVENING WHERE IT SLOWLY DISSIPATES ON SUN.  FORECASTERS TENDING TO
LEAN TOWARDS NAM SOLUTION FOR NEXT 36 HOURS DUE TO ITS HIGHER
RESOLUTION.

.ANALYSIS AND UPPER LEVELS...CURRENTLY A WARM FRONT OVER THE NORTHERN
GULF IS GENERATING MODERATE TO HEAVY RAIN FROM SOUTHERN KENAI
PENINSULA OVER TO ICY BAY. STRONG SOUTH WINDS OVER THE GULF  WILL
HELP TO TRANSPORT GULF MOISTURE ONSHORE THROUGH FRI EVENING. SSMI
IMAGERY INDICATES COPIOUS MOISTURE OVER THE GULF HOWEVER THE
PROGRESSIVE EASTWARD MOVEMENT OF THIS PATTERN WILL ALLEVIATE ANY
SERIOUS FLOODING IN ANCHORAGE AOR.

.SHORT TERM FORECAST...
BERING REGION..LOW CLOUDS WITH PATCHY FOG THROUGH THE WEEKEND. A WEAK
LOW MOVING JUST SOUTH OF THE WESTERN AND CENTRAL ALEUTIANS MAY
GENERATE SOME LIGHT RAIN BUT OTHERWISE MINIMAL IMPACT.

SOUTHWEST...CONTINUED CLOUDY WITH RAIN THROUGH SATURDAY EVENING. RAIN
TURNING TO SHOWERS ON SUNDAY FROM WEST TO EAST. AREAS OF FOG ALONG
THE COAST SAT. MODERATE NORTHWEST WINDS DEVELOPING ON SAT WITH COOLER
AIR MOVING IN MON MORNING FROM THE NORTHERN BERING.

SOUTHCENTRAL...RAIN OR SHOWERS OVER MOST OF THE REGION.  RAIN HEAVY
ALONG THE COAST AT TIMES THROUGH MIDNIGHT.  NOT EXPECTING ANY
FLOODING WITH CURRENT MODEL RAINFALL AMOUNTS AND LOW RIVER LEVELS.
MAIN AREA OF RAIN MOVES EASTWARD OVERNIGHT. WOULD EXPECT LIGHT RAIN
SAT MORNING BUT MODERATE AMOUNTS AGAIN SAT AFTERNOON AND NIGHT.

.LONG TERM FORECAST...
RESIDUAL LOW IN THE GULF SLOWLY DISSIPATES TUE AND WED...WOULD EXPECT
SOME SHOWERS OVER SOUTHCENTRAL ZONES. MODELS INDICATING A TROUGH FROM
SIBERIA MOVES INTO THE NORTHERN BERING TUE MORNING BRINGING A FRONT
AND CHANCE OF RAIN TO WESTERN ZONES AND EASTERN HALF OF BERING TUE
EVENING THROUGH WED. NEXT LOW IN THE WESTERN ALEUTIANS MOVES THROUGH
WED EVENING.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...GALES 120 125 129
FIRE WEATHER...DONE FOR SEASON

JMP AUG 11