Gale Warning 619, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
120 PM AKDT THU OCT 9 2008

.ANALYSIS AND UPPER LEVELS...
THIS AFTERNOON...A STRONG 963 MB LOW WITH STORM FORCE WINDS IS
POSITIONED IN THE SOUTHERN BERING SOUTHWEST OF SAINT PAUL. A WARM
FRONT STRETCHES OUT EAST AND AHEAD OF THE LOW FROM THE KILBUCK
MOUNTAINS TO ILIAMNA TO COASTAL SOUTHCENTRAL. SOME SNOW IS OCCURRING
OUT AHEAD OF THE FRONT WITH MUCH WARMER TEMPERATURES BEHIND IT. THE
MORE SIGNIFICANT FEATURE IS A SECONDARY STRENGTHENING FRONT IN THE
WESTERN GULF WITH A TRIPLE POINT LOW DEVELOPING AROUND KAMISHAK BAY
TONIGHT. THIS FRONT WILL BRING THE STRONGEST WINDS TO SOUTHCENTRAL.

.MODEL DISCUSSION...
MODELS ARE IN GOOD AGREEMENT OVERALL THROUGH THE SHORT TERM. SOME
DISAGREEMENTS ARISE IN THE LONG TERM...BUT ALL MODELS AGREE ON
CONTINUING THE VERY ACTIVE PATTERN.

.SHORT TERM FORECAST...
SOUTHCENTRAL...
AN INITIAL WARM FRONT WELL AHEAD OF THE BERING LOW IS BRINGING MORE
OVERRUNNING SNOW THAN ORIGINALLY EXPECTED TO PORTIONS OF
SOUTHCENTRAL. AS THE WARM FRONT MOVES THROUGH THE REST OF
SOUTHCENTRAL EARLY THIS EVENING...TEMPERATURES WILL WARM VERY
QUICKLY ALOFT WITH MOST PLACES CHANGING TO RAIN. THE BIGGER CONCERN
IS THE NEXT FRONT THAT THE MASSIVE BERING LOW WILL THROW AT US
TONIGHT. THE FRONT IS INTENSIFYING THIS AFTERNOON AS IT MOVES NORTH
THROUGH THE WESTERN GULF. GALE TO STORM FORCE WINDS ACCOMPANY THE
FRONT AND WINDS WILL ONLY INTENSIFY TONIGHT AS THE FRONT REACHES THE
NORTH GULF COAST. A TRIPLE POINT LOW MAY ALSO DEVELOP IN KAMISHAK
BAY AND MOVE UP COOK INLET...POSSIBLY FURTHER ENHANCING THE PRESSURE
GRADIENT. A HIGH WIND WARNING IS IN EFFECT FOR TURNAGAIN
ARM...PORTAGE VALLEY...AND THE HIGHER ELEVATIONS OF ANCHORAGE FOR
TONIGHT. RAIN FROM THIS SYSTEM WILL BE HEAVY ESPECIALLY ALONG THE
COAST...AND A SMALL STREAM FLOOD ADVISORY IS IN EFFECT FOR THE ZONES
AROUND PRINCE WILLIAM SOUND. THE FRONT MOVES INLAND FRIDAY MORNING
WITH WINDS SUBSIDING AND PRECIP TAPERING OFF OVER SOME AREAS FRIDAY
AFTERNOON. HOWEVER...THE LOW OUT IN THE BERING WILL WEAKEN AND MOVE
TO NEAR KODIAK SATURDAY...KEEPING SHOWER ACTIVITY AROUND THROUGH THE
WEEKEND OVER MOST OF SOUTHCENTRAL. THE WARMER AIRMASS SHOULD REMAIN
OVER SOUTHCENTRAL UNTIL SUNDAY...WHEN COLDER TEMPERATURES RETURN.

SOUTHWEST MAINLAND...
STRONG FRONT MOVING ONSHORE THE SOUTHWEST MAINLAND. SNOW HAS MOSTLY
CHANGED TO RAIN OVER BRISTOL BAY. THE FRONT WILL PUSH INTO THE
KUSKOKWIM VALLEY TONIGHT WITH A DECENT SHOT OF SNOW AHEAD OF THE
FRONT BEFORE THE FRONT MOVES THROUGH LATE TONIGHT AND TOMORROW
MORNING AND CHANGES THINGS OVER TO A RAIN SNOW MIX. THINGS ARE
TRICKER FOR THE KUSKOKWIM DELTA...AS THE FRONT DOES NOT LOOK LIKE IT
WILL PUSH MUCH FURTHER NORTH AND WEST MEANING THAT THEY MAY NOT
CHANGE OVER TO RAIN AND WILL SEE SOME DECENT SNOWFALL ACCUMULATIONS.
STRONGER NORTHEAST WINDS WILL PERSIST OVER THE KUSKOKWIM DELTA...BUT
BELIEVE THE SNOW WILL BE TOO WET AND TEMPS TOO WARM FOR SNOW TO BLOW
AROUND ENOUGH TO CREATE BLIZZARD CONDITIONS. WILL HAVE TO WATCH THIS
CLOSELY THOUGH THROUGH TOMORROW MORNING. AS THE BERING LOW MOVES
INTO THE WESTERN GULF OF ALASKA...A COLDER AIRMASS WILL MOVE INTO
ALL OF THE SOUTHWEST MAINLAND ON SATURDAY. WILL HAVE TO WATCH FOR
SNOWFALL ACCUMULATIONS IN THE EASTERN HALF OF THE SOUTHWEST MAINLAND
SATURDAY ON THE NORTHWEST SIDE OF THE GULF LOW.

BERING SEA/ALEUTIANS...
A MONSTER 963 MB LOW OUT IN THE ALEUTIANS NEAR BUOY 46073 SOUTHWEST
OF THE PRIBILOFS WILL MOVE SOUTHEAST INTO THE NORTH PACIFIC AND THEN
EAST TOWARD KODIAK...WEAKENING ALL ALONG. THE STRONGEST WINDS WITH
THE LOW AS WELL AS MOST OF THE PRECIP WILL CONTINUE TO BE ON ITS
WEST SIDE. AS THE LOW MOVES INTO THE WESTERN GULF...LOOK FOR STRONG
COLD ADVECTION AND SHOWERS IN THE EASTERN BERING/ALEUTIANS FRIDAY
AFTERNOON THROUGH SATURDAY. A STRONG FRONT MOVES INTO THE WESTERN
ALEUTIANS SATURDAY NIGHT...KEEPING THE ACTIVE PATTERN ALIVE.

.LONG TERM FORECAST...
MODELS DISAGREE ON DETAILS...BUT GENERALLY SPEAKING IT LOOKS LIKE AN
ACTIVE PROGRESSIVE FALL WEATHER PATTERN WILL CONTINUE THROUGH NEXT
WEEK.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...HIGH WIND WARNING 101 125.
MARINE...STORM WARNING 120 125 172 175 185.
         GALE WARNING 125 129 130 132 155 160 165 170 171 176 179
         180.
FIRE WEATHER...NONE.

FOISY OCT 08