Flood in Alaska, October 1, 2012

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
145 PM AKDT SUN SEP 30 2012

HIGH PRESSURE HAS BUILT ACRS INTR AK NICELY AND WILL SLOWLY DRIFT EAST
SUN EVENING. THIS WILL MAKE FOR A COLDER NIGHT MOST AREAS EAST OF THE
ALASKA RANGE. LIGHT WINDS WILL ALLOW THE AREAS OF LOW STRATUS/FOG TO BE
MORE WDSPRD THAN WAS SEEN SUNDAY MORNING. TEMPS WILL DROP INTO THE TEENS
IN THE USUAL COLD AREAS OF SCNTRL AK AND EASILY DROP BELOW 20F IN ZONE
141, DEPENDING ON HOW FAST THE SKIES CLEAR. SEPTEMBER RECORD FOR
ANCHORAGE IS 19 SET IN 1992. SCIENCE CENTER WAS 21 SUN MORNING. WITH THE
CURRENT LOCATION OF THE PAFC SITE, THAT RECORD IS SAFE.

PRECIPITATION FROM THE BERING SEA FRONTAL SYSTEM HAS MADE LANDFALL ALONG
THE SOUTHWEST COAST SUN MORNING. BOTH THE GFS AND NAM LOOK ON THE MARK
BY SLIDING PRECIP INTO BRISTOL BAY AND THE SOUTHWESTERN KUSKOKWIM VALLEY
SUNDAY NIGHT. I DON'T XPECT ANY SIG SNOW AMOUNTS SINCE MILD SOUTH AND
SOUTHWEST WIND WILL RAPIDLY CHANGE SNOW TO RAIN BEGINNING AS EARLY AS
THIS AFTERNOON.

COLD UPPER LOW IN THE GULF WILL KICK EASTWARD TO NEAR YAKUTAT BY AROUND
MID NIGHT TAKING THE SNOW SHOWERS WITH IT. PLACES LIKE NEBESNA MAY KEEP
CLOUDS AND LIGHT SNOW SHOWERS UNTIL EARLY MONDAY MORNING.

UPPER TROF DROPPING SOUTHEAST ACROSS THE WESTERN BERING WILL HOOK UP
WITH THE NORTHERN PORTION OF THE TROPICAL MOISTURE CURRENTLY SOUTH AND
SOUTHWEST OF THE WESTERN ALEUTIANS. THIS WILL STRENGTHEN WHAT IS NOW A
COMPLEX BUT WEAK SURFACE LOW BETWEEN 42N AND 48N NEAR 170W. THE LACK OF
COLD AIR WILL KEEP THIS SYSTEM FROM DEEPENING INTO TOO BIG OF A STORM.
THE GFS MOVES A 991 MB CENTER TO 80 NM WEST OF NIKOLSKI MON AFTERNOON.
35 TO 45 KT WINDS OVER THE FOX ISLANDS WILL ACCOMPANY THIS STORM.  LOW
THEN WEAKENS AS IT MOVES TOWARD BRISTOL BAY TUESDAY AFTERNOON.

990 MB TROPICAL STORM NEAR 44N 150E MOVES TO 495 NM SOUTHWEST OF SHEMYA
MONDAY AFTERNOON AND STILL POSSES TROPICAL CHARACTERISTICS. FROM THIS
POINT ON IT GRADUALLY BECOMES EXTRA TROPICAL, AND STRENGTHENS AS IT
TRACKS EAST JUST SOUTH OF 50N. AS THE 977 MB CENTER CLOSES IN ON 174W IT
BEGINS TO TAKE A TURN TO THE NORTHEAST AND ALSO MOVES TO 80 NM WEST OF
NIKOLSKI WEDNESDAY MORNING. AT THIS POINT IN TIME ONLY MINIMUM GALES FOR
THE EASTERN ALEUTIANS SINCE THE BULK OF THE COLD AIR REMAINS BACK IN THE
WESTERN BEING SEA AND RUSSIA. BUT THAT COULD CHANGE.

WEDNESDAY AND BEYOND AREAS EAST OF 152W WILL BE MOSTLY DRY WITH SUNSHINE
UNDER UPPER HIGH PRESSURE. WEST OF 152W CONDITIONS WILL BECOME CLOUDIER,
WETTER AND WINDIER ESPECIALLY WEST OF THE ALASKA RANGE.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...FLOOD WARNG TO BECOME ADVISORY FOR KENAI LAKE.
MARINE...SEE MARINE FORECASTS.
FIRE WEATHER...NOTHING.

DPERCY SEP 12