Gale Warning 372, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
1203 PM AKST FRI NOV 21 2008

.ANALYSIS...
MAJOR UPR LOW COMPLEX OVR THE RUSSIAN FAR EAST HAS STARTED TO
MOVE EASTWARD. 12Z RAOB AT UHPP SHOWS -38C AT 500 HPA WITH A WEST
WIND INDICATING THE UPR LOW CENTER HAS REACHED THE NW PACIFIC
WITH THE COLDEST AIR ALF. VERY STG JET 250 HPA FROM CENTRAL ASIA
TO AN EXIT NEAR 45N 150W WHERE YOU CAN SEE THE END OF A
BAROCLINIC LEAF ON GOES-W. A 976 MB STORM CENTER SLAMMED INTO THE
CHARLOTTES THIS MORNING...BUT NOT TOO MUCH WIND YET ON OUR SIDE
OF DIXON. OLD MAIN GULF LOW S OF YAKUTAT AROUND 983 MB. SPOTTY
LIGHT SNOW NORTH THIS MORNING AND SPOTTY RAIN S.

.SHORT TERM...SATELLITE IMAGERY THIS MORNING SHOWS A WEAKENING
VERTICALLY STACKED LOW IN THE NORTHEASTERN GULF AND VERY STRONG
LOW CURRENTLY OVER THE QUEEN CHARLOTTE ISLANDS AND TRACKING
NORTHEAST. RADAR IS SHOWING A GENERAL DECREASE IN THE SHOWER
ACTIVITY TRACKING NNW ASSOCIATED WITH THE VERTICALLY STACKED LOW
AS MORE STRATIFORM PRECIPITATION ASSOCIATED WITH THE QUEEN
CHARLOTTES LOW SPREADS NORTH. HAVE BEEN SEEING STEADY MODERATE
RAIN RATES IN THE SOUTHERN ZONES NOW FOR ABOUT 3 HOURS. THE
NORTHERLY PRESSURE GRADIENT CREATED BY THIS LOW WILL KEEP WINDS
NORTHERLY...BACKING FROM NORTHEAST TO NORTHWEST THROUGHOUT THE
DAY...WITH STRONGEST WINDS AND GUSTS IN LOCATIONS CLOSEST TO THE
DIXON ENTRANCE. STILL...NO ADVISORY LEVEL GUSTS EXPECTED BASED ON
CURRENT TRACK OF THIS LOW. WINDS SHOULD WEAKEN LATER THIS
AFTERNOON IN THE SOUTHERN HALF OF THE PANHANDLE AS THE LOW TRACKS
NORTHEAST OVER MISTY FJORDS AND THEN INTO BRITISH COLUMBIA.
LIKEWISE OVER THE NORTHERN PANHANDLE LATER TONIGHT...WHERE A
NORTHEAST PRESSURE GRADIENT RESULTING FROM THE VERTICALLY STACKED
LOW WILL RELAX AS THIS LOW CONTINUES TO WEAKEN.

AN UPPER TROUGH AND ASSOCIATED COLDER UPPER AIR WILL BEGIN TO
MOVE OVER THE PANHANDLE LATER THIS AFTERNOON. LATE
TONIGHT...EXPECT
TO SEE A MUCH WEAKER LOW LEVEL TROUGH FOLLOW SUIT AND ADVECT SOME
COOLER AIR INTO THE PANHANDLE FROM THE WEST. IN SPITE OF
THIS...ONSHORE FLOW SHOULD PUSH THE RAIN/SNOW LINE NORTH TO JUST
SOUTH OF ICY STRAIT SO THE BEST CHANCE FOR ANY SIGNIFICANT A SNOW
ACCUMULATION TONIGHT WILL BE LIMITED TO THE THE HYDER
AREA WITH AROUND 4 INCHES...AND THE NORTHERN INNER CHANNELS TO
INCLUDE HOONAH AND JUNEAU...WHERE 1 TO 2 INCHES IS POSSIBLE.
MIXED PRECIP POSSIBLE DOWN TO ABOUT PETERSBURG WITH RAIN SOUTH OF
THERE.

.LONG TERM...
ALL 12Z OPS MODELS HAVE A STORM CENTER DEVELOPING SW OF THE
CHARLOTTES AGAIN ON SAT NITE. PREFER GFS-UKMET-NAM SOLN OF
KEEPING A RESIDUAL WELL-DEFINED SFC LOW IN THE WESTERN GULF AT
THAT TIME. THE TRACK ON THIS STORM BECOMES MORE TOWARD THE N THAN
THE LAST SYSTEMS DUE TO THE HUGE PLANETARY PATTERN CHANGE OF THE
MAJOR UPR LOW/TROF ESTABLISHING IN THE BERING STRAIT AND ALG 160W
OR SO. PREFER AK-GFS-40 MOVING THE CENTER INTO THE SOUTHERN
PANHANDLE BY 06Z MON RAPIDLY DYING. NOW THE FUN BEGINS. NEW STORM
HEADS FOR KODIAK ISL MON WITH A STRONG FRONT IN THE GULF ACCEPTED
AND SHOWN ON HPC PROGS YESTERDAY. SECOND STORM IN GULF ON WED
ACCEPTED. ALL MODELS AND ENSEMBLES FORECAST A MONSTER LOW JUST S
OF UNALASKA NEXT FRI WHICH...I KNOW...I KNOW...THATS WAY OUT
THERE BUT IT IS SUPPORTED ALF BY A PLANETARY SCALE LOW. AS PER
PREVIOUS FORECAST DISC WE GET WET WARM AND PERIODS OF WIND.

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...SMCR 11 12 13 21 22 33 34 35 36 41 42 43 51 52.

FRITSCH/JCC