High Wind Watch 1, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 PM AKST SAT JAN 9 2010

.ANALYSIS AND UPPER LEVELS...
AN WEAKENING UPPER LEVEL RIDGE WHICH CURVES WESTWARD OUT OF NORTHERN
BRITISH COLUMBIA CONTINUES TO WEAKEN AND MOVE EASTWARD. A BROAD
SECOND RIDGE AND ASSOCIATED HIGH PRESSURE SYSTEM REMAINS FIXED OVER
THE NORTH BERING SEA AND WESTERN ALASKA. A LARGE UPPER LEVEL TROUGH
ENCOMPASSES MUCH OF THE NORTHEASTERN PACIFIC WITH A SERIES OF WEAK
SHORTWAVES AND LOW PRESSURE SYSTEMS ROTATING AROUND A COMMON LOW
PRESSURE SYSTEM CENTERED ABOUT 700 MILES SOUTH OF DUTCH HARBOR. A 190
KT JET LOCATED SOUTHWEST OF THIS LOW WILL AID IN STRENGTHENING THIS
SYSTEM OVER THE WEEKEND.

AT THE SURFACE...A STRONG ARCTIC HIGH PRESSURE SYSTEM LOCATED 350
MILES NORTHWEST OF BARROW WILL CONTINUE TO BRING SUB-ZERO DAYTIME
TEMPERATURES TO THE NORTHERN HALF OF THE STATE. AN INVERTED RIDGE
EXTENDS SOUTHEASTWARD FROM THIS HIGH INTO THE NORTHWEST TERRITORY. AN
ELONGATED 963 MB LOW PRESSURE SYSTEM IS STACKED UNDER THE
AFOREMENTIONED UPPER LEVEL LOW SOUTH OF THE ALEUTIANS. A SERIES OF
WEAK SHORTWAVES ARE ROTATING AROUND THE NORTHEAST QUADRANT OF THIS
LOW...ONE OVER THE EASTERN GULF OF ALASKA AND ANOTHER OVER THE KENAI
PENINSULA. THESE SHORTWAVES ARE RESULTING IN ISOLATED SHOWERS OVER
THE GULF.

.MODEL DISCUSSION...
THE MODELS ARE IN GOOD AGREEMENT THROUGH MONDAY...THOUGH THE NAM
MODEL HANDLES THE INTENSIFYING PRESSURE GRADIENT ALONG THE CHUGACH
MOUNTAINS AND OVER THE NORTHERN SUSITNA VALLEY BETTER THAN THE GFS.

.SHORT TERM FORECAST...
UPPER LEVELS...THE HIGH OVER THE NORTHERN BERING SEA AND CONNECTING
RIDGE THROUGH THE MAINLAND ALASKA WILL PERSIST THROUGH MONDAY. AN
UPPER RIDGE OVER THE NORTHEAST PACIFIC WILL MOVE NORTH AND BECOME
NEARLY STATIONARY ABOUT 200 MILE SOUTHEAST OF KODIAK SUNDAY NIGHT.

SOUTH-CENTRAL ALASKA AND THE GULF...
A DRY ARCTIC AIRMASS MOVING INTO THE SOUTH-CENTRAL INTERIOR WILL
KEEP SKIES MOSTLY CLEAR BUT WILL ALSO DROP TEMPERATURES IN THE COPPER
RIVER BASIN AND THE NORTHERN SUSITNA VALLEY. THE INCREASING PRESSURE
GRADIENTS ALONG THE ALASKA RANGE AND THE CHUGACH MOUNTAINS WILL
PRODUCE VERY STRONG GAP WINDS THROUGH BROAD PASS...THOMPSON PASS AND
THE COPPER RIVER DELTA MONDAY. LOW WIND CHILL TEMPERATURES COULD ALSO
DEVELOP IN THESE AREAS.

A WEATHER FRONT OVER THE NORTHEAST PACIFIC WILL MOVE NORTH...BUT
STALL OVER THE CENTRAL GULF SUNDAY EVENING. AREAS OF SNOW WILL FALL
ALONG THE OUTER GULF COAST SUNDAY NIGHT AND MONDAY. KODIAK ISLAND
WILL REMAIN MOSTLY RAINY THROUGH MONDAY.

SOUTHWEST ALASKA...THE NORTHEAST FLOW ACROSS THE AREA WILL HELP
MAINTAIN THE CLEAR SKIES AND COLD TEMPERATURES OVER THE KUSKOKWIM
VALLEY AND KUSKOKWIM DELTA THROUGH MONDAY. SHORT WAVES IN THE
EASTERLY FLOW ACROSS BRISTOL BAY WILL BRING OCCASIONAL LIGHT SNOW
THROUGH THE SECTOR THROUGH MONDAY.

BERING SEA...NORTHEAST FLOW WILL CONTINUE OVER THE AREA THROUGH
MONDAY.

.LONG TERM FORECAST...
THE UPPER LOW SOUTH OF KODIAK ISLAND WILL REMAIN NEARLY STATIONARY
THROUGH WEDNESDAY. THE UPPER RIDGE OVER MAINLAND ALASKA WILL SLOWLY
WEAKEN FROM THE WEST THROUGH WEDNESDAY. A NEW STORM WILL BEGIN TO
MOVE INTO THE WESTERN ALEUTIANS WEDNESDAY.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...STORMS 130 132
         GALES 120 127 128 138 150 155

KS/NM JAN 10