Small Craft Advisory 305, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 AM ADT TUE APR 4 2006

.DISCUSSION...

00Z FORECAST SOLUTIONS OF NAM/GFS/UKMET ARE ALL IN REASONABLE
AGREEMENT THROUGH THE NEXT 24 HOURS IN DROPPING LOW NEAR COLD BAY
SOUTHEASTWARD INTO THE PACIFIC AND FORMING A NEW LOW EAST OF KODIAK
ISLAND THIS MORNING IN RESPONSE TO SHORT-WAVE ROUNDING UPPER TROUGH.
MODELS ALL PARK THIS NEW LOW OVER THE NORTHERN GULF TUESDAY NIGHT
THROUGH THURSDAY...WAITING FOR THE UPPER TROUGH TO SWING THROUGH AND
CLEAR EVERYTHING OUT. THERE ARE SLIGHT DIFFERENCES IN THE POSITION OF
THE LOW WHICH INTRODUCES UNCERTAINTIES ABOUT HOW MUCH MOISTURE WILL
MAKE IT OVER THE KENAI AND CHUGACH MOUNTAINS (IF ANY) INTO THE MAT
VALLEY-ANCHORAGE-WESTERN KENAI CORRIDOR. WILL STICK CLOSE TO THE
CURRENT FORECAST IN KEEPING A CHANCE OF SNOW IN THIS REGION UNTIL
THE UPPER TROUGH MOVES THROUGH ON THURSDAY.

IN THE MEANTIME...AREAS OF RAIN AND SNOW CONTINUE ACROSS SOUTHWEST
ALASKA AND SOUTHCENTRAL ALASKA THIS MORNING. THE KUSKOKWIM DELTA
COAST HAS BEEN EXPERIENCING BLIZZARD CONDITIONS ALL NIGHT JUST OUT
AHEAD OF OCCLUDED FRONT. EXPECT THESE CONDITIONS TO CONTINUE FOR
THE NEXT SEVERAL HOURS AND THEN BEGIN TO IMPROVE LATE MORNING AS
THE UPPER TROUGH SWINGS EASTWARD. THE SUSITNA VALLEY APPEARS TO BE
THE HARDEST HIT AS FAR AS SNOW TOTALS (10 INCHES YESTERDAY ALONG
PETERSVILLE ROAD). STEADY SNOW WILL CONTINUE TO FALL THROUGH THIS
MORNING AND DIMINISH IN INTENSITY THIS AFTERNOON AS LOW MOVES INTO
NORTHERN GULF AND FLOW BEGINS TO SHIFT AROUND TO THE NORTH. WINDS
THROUGH PORTAGE VALLEY AND TURNAGAIN ARM REMAIN STRONG (35 TO 55 KT)
BUT SHOULD DIMINISH FAIRLY QUICKLY LATE THIS MORNING AS EAST-WEST
SURFACE PRESSURE GRADIENT LOOSENS IN RESPONSE TO GULF LOW.

SOUTHWEST ALASKA WILL GRADUALLY CLEAR OUT TUESDAY NIGHT INTO
WEDNESDAY MORNING WHILE THE SOUTHERN MAINLAND WILL HAVE TO WAIT
UNTIL LATE IN THE WEEK. AS MENTIONED EARLY WILL NEED TO FINE TUNE
THE PRECIP FORECAST THE NEXT COUPLE DAYS AS MODELS KEY IN ON
POSITION OF SURFACE LOW OVER THE NORTHERN GULF.

OUT WEST...EXPECT GUSTY GALE FORCE WINDS TODAY ALONG EASTERN
ALEUTIANS/AKPENN IN COLD ADVECTION BEHIND DEPARTING LOW. RIDGE OF
HIGH PRESSURE OVER THE WESTERN TO CENTRAL BERING WILL PROGRESS
EASTWARD. THE FEW OBSERVATIONS OUT THERE SHOW A LOT OF LOW CLOUDS
UNDER THIS RIDGE. THE NEXT FRONTAL SYSTEM APPROACHES THE WESTERN
ALEUTIANS TUESDAY NIGHT AND TRACKS EASTWARD THROUGH THE WEEK.
MODELS INDICATE A STRONG LOW ARRIVING LATE THURSDAY INTO FRIDAY
AS THE PATTERN REMAINS PROGRESSIVE.

EXTENDED FORECAST...STILL LOOKS LIKE A PROGRESSIVE LOW AMPLITUDE
PATTERN WITH SURFACE LOWS GENERALLY MOVING WEST TO EAST ACROSS THE
BERING AND GULF OF ALASKA. THEREFORE...EXPECT CONDITIONS SIMILAR
TO WHAT WE HAVE BEEN EXPERIENCING THE PAST WEEK.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...BLIZZARD WARNING ZONE 155 ALONG THE COAST.
MARINE...GALES 120 130 155 165 170 172 175 176 179 180.
FIRE WEATHER...NONE.

SEB APR 06