High Wind in Alaska, September 18, 2006

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
230 PM ADT MON SEP 18 2006

.DISCUSSION...
MODELS INITIALIZED FAIRLY WELL. IT SEEMS THE NAM INITIALIZED THE
UPPER LEVELS A BIT BETTER OVER THE MAINLAND. HOWEVER...THE SURFACE
LOW IS HANDLED GOOD BY BOTH. 18Z NAM AND 12Z GFS IN GOOD AGREEMENT ON
PROGRESSION OF SURFACE FEATURES.

UPPER LEVELS...TROUGH OVER THE EASTERN BERING WITH CLOSED LOW JUST
SOUTH OF THE EASTERN ALEUTIAN ISLANDS. IN ADDITION...A SHORT WAVE
RIDGE IS OVER THE GULF WITH AN EXITING LOW APPROACHING VANCOUVER
ISLAND. RIDGE PUSHED EAST TONIGHT OVER THE GULF AS SHORT WAVE AND JET
ROUND THE CLOSED LOW NOW OVER THE ALASKA PENINSULA. THIS WILL PUSH
THE FRONT IN THE WESTERN GULF TOWARD THE NORTHERN GULF COAST BY LATE
TUESDAY MORNING. JET PUSHES TO THE PANHANDLE WITH UPPER LOW REMAINING
OVER THE ALASKA PENINSULA TUESDAY. THIS ALLOWS THE LOW TO FILL AND
SLOWLY MOVE EAST THROUGH THE DAY TO THE NORTHERN GULF. IT WILL BE
PUSHED INLAND AS A RESULT OF ANOTHER WAVE DIGGING SOUTH IN THE
WESTERN BERING. THIS IS DUE TO THE FACT IT WILL CHANGE THE
ORIENTATION OF THE JET. THE NEW TROUGH OVER THE BERING TO MERGE WITH
THE MAINLAND LOW WITH AN AXIS NEAR 150W. RIDGE MOVES INTO THE WESTERN
BERING THURSDAY AND PROGRESSES SLOWLY ACROSS THE BERING INTO
SATURDAY. THE LOW EAST OF THE ALASKA RANGE REMAINS BUT JUST PUSHED
EAST OUT OF SOUTHWEST ALASKA. A NEW LOW MOVES PAST KAMCHATKA TO
SHEMYA FRIDAY INTO SATURDAY.

SURFACE WEST OF THE ALASKA RANGE...VIGOROUS LOW JUST EAST OF DUTCH
HARBOR THIS AFTERNOON. STRONG BAROCLINIC ZONE ON THE NORTH SIDE AND
BACKSIDE OF THE LOW. THIS IS PRODUCING VERY STRONG WINDS ESPECIALLY
IN THE AREA OF COLD ADVECTION IMMEDIATELY BEHIND THE LOW. THIS AREA
IS MODERATING QUICKLY AS THE LOW WRAPS AROUND ITSELF. LOW FILLS 8 MB
OVERNIGHT...SO EXPECT WINDS TO DIMINISH. GOOD AMOUNTS OF
PRECIPITATION ACCOMPANYING THIS LOW. LOW IS STACKED AT THIS TIME AS
WELL AND SLOWLY MOVES FROM THE ALASKA PENINSULA TUESDAY INTO THE
WESTERN GULF. NORTHERLY WINDS BEHIND THE LOW WILL SLOWLY WEAKEN INTO
TUESDAY AS WELL OVER THE EASTERN BERING. HOWEVER...GOOD GRADIENT OVER
THE WATER AREAS SOUTH OF THE ALASKA PENINSULA AND BRISTOL BAY FOR
MODERATE WINDS INTO WEDNESDAY BEFORE IT LIFTS INLAND. ANOTHER LOW
MOVING SOUTH OUT OF THE WESTERN BERING TO BRING MODERATE WINDS THERE
ALONG WITH SOME PRECIPITATION. THIS LOW TO WORK EAST WEDNESDAY AND
THURSDAY ALONG THE ALEUTIAN CHAIN AS HIGH PRESSURE MOVES INTO THE
WESTERN BERING. THE LOW WILL MERGE WITH THE BROAD AREA OF LOW
PRESSURE OVER THE GULF AND SOUTH CENTRAL THURSDAY. MODERATE NORTHERLY
WINDS WILL REMAIN OVER THE BERING SEA. HIGH PRESSURE MOVES EAST
THROUGH THE BERING INTO SATURDAY. THIS WILL MOVE THE LOW OVER SOUTH
CENTRAL AND THE GULF EAST. IN THE MEANTIME...A LOW AND ASSOCIATED
FRONT MOVE TO THE WESTERN ALEUTIAN ISLANDS.

SURFACE EAST OF THE ALASKA RANGE...STRONG FRONT MOVING NORTH IN THE
GULF THIS AFTERNOON AND TO THE NORTHERN GULF COAST TONIGHT. THE
ASSOCIATED LOW WILL BE OVER THE ALASKA PENINSULA LATE TONIGHT. STRONG
WINDS AND MODERATE TO HEAVY AMOUNTS OF PRECIPITATION ALONG THE COAST
AND IN THE GULF. THIS WILL MOST LIKELY RESEMBLE OUR TYPICAL DOWNSLOPE
PRECIPITATION PATTERN. ORIENTATION OF THE FRONT...COMBINED WITH
MODERATE TO STRONG SOUTHEAST FLOW ALOFT WILL CREATE STRONG WINDS
THROUGH SOUTH TO NORTH ORIENTED GAPS. THIS PATTERN WILL REMAIN
THROUGH TOMORROW BEFORE THE LOW AND FRONT BEGIN TO WEAKEN TUESDAY
EVENING AND MOVES OVER SOUTH CENTRAL ALASKA BY WEDNESDAY MORNING.
WILL SEE THEN AN INCREASE IN PRECIPITATION INLAND AS A RESULT. AN
AREA OF BROAD LOW PRESSURE WILL REMAIN OVER SOUTH CENTRAL AND THE
GULF THROUGH THURSDAY. A STRONG LOW TO MOVE ACROSS JUST SOUTH OF THE
GULF AND HEAD TOWARD THE PANHANDLE THURSDAY INTO FRIDAY. RESIDUAL LOW
PRESSURE TO REMAIN OVER THE GULF INTO SATURDAY WITH ISOLATED TO
SCATTERED SHOWERS. MOST PRECIPITATION WILL BE ALONG THE NORTHERN GULF
COAST WITH SOME ISOLATED SHOWERS ELSEWHERE. MAY ALSO SEE SOME
MODERATE WESTERLY WINDS THROUGH WEST TO EAST GAPS AS A RESULT AT THIS
TIME.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...HIGH WIND WARNING ZONE 185
MARINE...STORM 170 172
         GALE 138 150 155 160 165 171 179 180 185
FIRE WEATHER...NONE

JN SEP 06