High Wind Warning 24, NWS Anchorage, AK

000 
WWAK71 PAFC 300008
NPWAER

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE ANCHORAGE AK
408 PM ADT THU OCT 29 2009


AKZ131-300115-
/X.EXP.PAFC.HW.W.0024.000000T0000Z-091030T0000Z/
NORTHEAST PRINCE WILLIAM SOUND-
INCLUDING THE CITIES OF...VALDEZ...THOMPSON PASS
408 PM ADT THU OCT 29 2009

...HIGH WIND WARNING HAS EXPIRED...

WINDS HAVE DIMINISHED IN THE VALDEZ AREA THIS AFTERNOON. WINDY
CONDITIONS ARE EXPECTED TO CONTINUE FOR THE NEXT COUPLE OF DAYS.
CHANNELED AREAS CAN EXPECT WIND GUSTS OF 55 TO 65 MPH THROUGH
SATURDAY NIGHT.


$$

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
545 AM AKDT THU OCT 29 2009

.ANALYSIS AND UPPER LEVELS...

A RATHER AMPLIFIED AND QUASI-STATIONARY WEATHER PATTERN CONTINUES FOR
THE NEXT SEVERAL DAYS. A STRONG UPPER RIDGE REMAINS OVER THE BERING
STRAIT EXTENDING DOWN THE WEST COAST OF ALASKA AND INTO THE EASTERN
BERING SEA AND ALEUTIANS. A CUT-OFF UPPER LOW CONTINUES TO RESIDE IN
THE GULF SUPPORTING A TROUGH OF LOW PRESSURE IN THE NORTHERN GULF. A
STRONG NORTHERLY JET RESIDES ALONG AND JUST WEST OF THE ALASKA RANGE
AND WILL REMAIN THERE INTO A GOOD PORTION OF THE WEEKEND. OUT
WEST...A STRONG UPPER LOW OVER NORTHEASTERN ASIA WILL CONTINUE TO SIT
AND SPIN...WITH A SERIES OF DISTURBANCES MOVING WEST TO EAST ACROSS
THE WESTERN BERING SEA BUT WEAKENING AND SLOWING AS THEY ENCOUNTER
THE DOWNSTREAM RIDGE.

.MODEL DISCUSSION...

ALL MODELS ARE IN GOOD AGREEMENT THROUGH SATURDAY WITH CURRENT
GRIDS...BASICALLY DEPICTING A TROUGH OF LOW PRESSURE IN THE NORTHERN
GULF AND HIGH PRESSURE OVER THE NORTHERN INTERIOR OF THE STATE
INDUCING A TIGHT NORTH-SOUTH PRESSURE GRADIENT...THUS INITIATING
STRONG NORTHERLY FLOW ACROSS MOST OF THE MAINLAND IN OUR AREA OF
RESPONSIBILITY. THE MAJORITY OF THE TIME SPENT ON THIS FORECAST
PACKAGE WAS SPENT UPDATING THE STRONG WINDS EXPECTED THROUGH
NORTH-SOUTH TERRAIN GAPS THROUGH SATURDAY.

.SHORT TERM FORECAST...

SOUTH AND EAST OF THE ALASKA RANGE...NORTH TO NORTHEASTERLY FLOW IN
THE MID LEVELS OF THE ATMOSPHERE COMBINED WITH COLD ADVECTION AND A
TIGHTENED NORTH-SOUTH PRESSURE GRADIENT AT THE SURFACE HAVE COMBINED
TO BRING STRONG WINDS WITH A NORTHERLY COMPONENT TO NEARLY ALL OF THE
REGION. WINDS THROUGH THOMPSON PASS OVERNIGHT EXCEEDED EXPECTATIONS
WITH GUSTS 50 TO 65 MPH...AS A SHORTWAVE HAS MOVED SOUTH AND WEST
OVER THE COPPER RIVER BASIN INTO SOUTHCENTRAL ALASKA THIS MORNING.
WINDS HAVE ALSO PICKED UP THROUGH THE MATANUSKA VALLEY THIS
MORNING...BREAKING THE DENSE FOG THAT WAS IN PLACE NEAR THE PALMER
AREA. WINDS IN ANCHORAGE SHOULD CONTINUE TO INCREASE TODAY AS THE
WINDS OUT OF THE MATANUSKA VALLEY BEND TOWARDS TOWN AS THE PRESSURE
GRADIENT BETWEEN TALKEETNA AND ANCHORAGE CONTINUES TO INCREASE TODAY.
AS THE PATTERN IS LOCKED IN PLACE THROUGH AT LEAST SATURDAY...WE
SHOULD CONTINUE TO SEE WINDS REMAIN STRONG ACROSS THE REGION WITH
PEAKS AND VALLEYS DEPENDING ON THE TIMING OF SHORTWAVES MOVING FROM
NORTHEAST TO SOUTHWEST IN THE NORTHEASTERLY FLOW ALOFT.

SOUTHWEST ALASKA...

CONTINUED COLD ADVECTION AND OCCASIONALLY GUSTY WINDS WILL BE THE
MAIN STORY THROUGH THE NEXT SEVERAL DAYS INTO THE WEEKEND. A
NORTH-NORTHEASTERLY JET WILL REMAIN ALONG AND JUST WEST OF THE ALASKA
RANGE...WHICH WILL MOVE MINOR DISTURBANCES QUICKLY ACROSS THE EASTERN
PART OF THIS REGION. THUS...PRECIPITATION WILL BE MINIMAL AND SKIES
MOSTLY ON THE CLEAR SIDE EXCEPT FOR THE OCCASIONAL FAST-MOVING
DISTURBANCE ALONG THE ALASKA RANGE. THE RIDGE APPEARS TO WEAKEN
SATURDAY AND THE JET MOVES SOUTH AND EAST INTO SUNDAY ACROSS THE
KENAI PENINSULA AND GULF OF ALASKA AS THE PATTERN BEGINS TO CHANGE
ONCE AGAIN.

BERING SEA/ALEUTIANS...

A SERIES OF LOWS WILL CONTINUE TO GRAZE THE WESTERN ALEUTIANS AND
BERING SEA AS THEY ROTATE AROUND A STRONG STATIONARY PARENT LOW OVER
NORTHEASTERN ASIA. ONE LOW WILL BRING A STRONGER FRONT INTO THE
WESTERN ALEUTIANS AND BERING SEA FRIDAY...BUT THIS WILL WEAKEN AND
SLOW AS IT ENCOUNTERS THE DOWNSTREAM RIDGE OVER THE EASTERN BERING
SEA. THERE WILL LIKELY TO CONTINUE TO BE STRONG WINDS AS A STRONG
PRESSURE GRADIENT CONTINUES BETWEEN APPROACHING FRONTS AND
DISTURBANCES FROM THE WEST AND THE QUASI-STATIONARY HIGH TO THE NORTH
AND EAST OVER THE MAINLAND THROUGH THE WEEKEND.

.LONG TERM FORECAST...

THERE ARE SIGNS THE HIGHLY AMPLIFIED AND QUASI-STATIONARY PATTERN
WILL TRY TO BECOME MORE PROGRESSIVE THE EARLY TO MIDDLE PARTS OF NEXT
WEEK. THIS WILL LIKELY RESULT IN A MUCH WEAKER RIDGE OVER THE
MAINLAND OF THE STATE...WITH THE STRONG UPPER LOW OVER EASTERN ASIA
MOVING INTO OR TOWARDS THE BERING SEA...AND APPROACHING DISTURBANCES
MOVING INTO THE GULF OF ALASKA AND TOWARDS SOUTHCENTRAL BY THE MIDDLE
OF NEXT WEEK.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...GALE WARNING...121 130 132 175 176 185
FIRE WEATHER...NONE.

CC OCT 09