Small Craft Advisory 243, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 PM AST TUE MAR 14 2006

.DISCUSSION...

A STRONG WIND EVENT IS ONGOING OVER PORTIONS OF SOUTHCENTRAL ALASKA.
THE REGION LIES BETWEEN A HIGH AMPLITUDE UPPER LEVEL RIDGE OVER THE
CENTRAL TO EASTERN BERING SEA AND A CLOSED LOW OVER SOUTHEAST ALASKA.
AN UPPER LEVEL JET EXTENDING FROM THE YUKON TO PRINCE WILLIAM SOUND
IS PROVIDING LOTS OF UPPER SUPPORT FOR THIS EVENT WITH HIGHER WINDS
ALOFT MIXING DOWNWARD. AT 1400 UTC THE GLENNALLEN WIND PROFILER
SHOWED 125 KT AT 350 MB. IN THE LOW LEVELS THERE IS A TIGHT
NORTH-SOUTH PRESSURE GRADIENT AND STRONG COLD ADVECTION FROM CANADA
INTO SOUTHCENTRAL. HIGH WIND WARNINGS REMAIN UP FOR VALDEZ AND THE
COPPER RIVER DELTA WHERE WIND INSTRUMENTS HAVE REPORTED GUSTS AS
HIGH AS 92 MPH. WIND DAMAGE HAS ALSO BEEN REPORTED IN VALDEZ. STRONG
WINDS ARE ALSO BEING FELT ACROSS THE COPPER RIVER BASIN AND THE
MATSU VALLEY. THE UPPER LEVEL JET WILL MOVE SOUTHWARD ACROSS THE
GULF TONIGHT AND WEAKEN IN RESPONSE TO THE WEAKENING OF THE BERING
SEA RIDGE. THE LOSS OF THIS UPPER SUPPORT WILL CAUSE WINDS TO
DECREASE OVERNIGHT. THE SURFACE PRESSURE GRADIENT WILL REMAIN TIGHT
OVER SOUTHCENTRAL THROUGH THE END OF THE WEEK SO THAT GUSTY WINDS
WILL CONTINUE IN THE NORMAL PLACES...BUT NOWHERE NEAR AS STRONG AS
TODAY. A WEAK SURFACE LOW OVER THE GULF WILL PERSIST THROUGH THE END
OF THE WEEK WITH MOST IF NOT ALL OF PRECIP REMAINING OFFSHORE.
OTHERWISE...EXPECT CLEAR SKIES AND COLD NIGHT-TIME TEMPS TO CONTINUE
ACROSS SOUTHCENTRAL FOR AT LEAST ANOTHER WEEK.

OUT WEST AN OCCLUDED FRONT IS PUSHING EASTWARD ACROSS THE CENTRAL
BERING SEA. IT WILL SLOW DOWN AS IT PUSHES UP AGAINST THE RIDGE TO
THE EAST TONIGHT AND THEN WILL DISSIPATE OVER THE EASTERN BERING ON
WEDNESDAY. THERE MAY BE A BRIEF PERIOD OF SNOW ALONG THE SOUTHWEST
COAST WEDNESDAY EVENING. OTHERWISE EXPECT MOST OF SOUTHWEST TO
REMAIN DRY. THE NEXT MAJOR SYSTEM TO AFFECT THE BERING SEA REGION IS
CURRENTLY FORMING OVER THE NORTHWEST PACIFIC. DEVELOPMENT IS BEING
DRIVEN BY A 160 KT UPPER LEVEL JET HEADING STRAIGHT FOR THE
ALEUTIANS. THE NAM/GFS/UKMET ALL AGREE ON A TRIPLE POINT LOW
DEVELOPING TONIGHT AND DEEPENING INTO THE LOW TO MID 960S AS IT
MOVES TO THE WESTERN ALEUTIANS WEDNESDAY EVENING. THERE IS SOME
DISAGREEMENT ON THE TRACK OF THE LOW. HAVE TRENDED TOWARD THE
NAM/UKMET SOLUTION FOR THIS AFTERNOONS FORECAST PACKAGE DUE TO
CONSENSUS. HIGH WIND WATCHES ARE IN EFFECT FOR THE CENTRAL AND
WESTERN ALEUTIANS WEDNESDAY EVENING THROUGH THURSDAY MORNING. THERE
IS SOME DECENT COLD ADVECTION ON THE BACK SIDE OF THE SYSTEM SO
MAY HAVE TO EXTEND THE WATCHES FURTHER OUT IN TIME. THERE IS STILL
PLENTY OF TIME TO EVALUATE THIS STORM SO WILL STICK WITH WATCHES
FOR NOW AND FINE TUNE THE FORECAST WITH THE NEXT COUPLE MODEL RUNS.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...HIGH WIND WARNING 131 AND 135.
         HIGH WIND WATCH 187 AND 191.
MARINE...GALE WARNING 120 121 172 175 176 185.

SEB MAR 06