Small Craft Advisory 765, NWS Anchorage, AK

AREA FORECAST DISCUSSION...CORRECTED
SOUTHCENTRAL AND SOUTHWEST ALASKA
400 AM ADT SUN AUG 27 2006

CORRECTED DATE.

.DISCUSSION...

...SUMMARY...
FOR TODAY...MAIN FEATURES OF INTEREST INCLUDE AN AREA OF LOW
PRESSURE OVER THE CENTRAL GULF OF ALASKA...ANOTHER LOW NEAR THE
COAST OF RUSSIA...AND A RIDGE IN BETWEEN OVER THE FAR EASTERN
ALEUTIANS EXTENDING INTO SOUTHWEST MAINLAND ALASKA. THESE THREE
FEATURES WILL MIGRATE EAST OVER THE NEXT FEW DAYS. THE LOW IN THE
GULF WILL MOVE INTO THE PANHANDLE ON MONDAY WITH THE RIDGE OF HIGH
PRESSURE MOVING INTO MAINLAND ALASKA. THE RIDGE AND DRY WEATHER OVER
THE MAINLAND WILL LAST UNTIL LATE TUESDAY OR WEDNESDAY. THE LOW NEAR
THE RUSSIAN COAST WILL MOVE SLOWLY EAST TO JUST WEST OF SAINT MATTHEW
ISLAND ON TUESDAY. MEANWHILE...A SHORTWAVE WILL INTERACT WITH A
STRONG BAROCLINIC ZONE OVER THE ALEUTIAN CHAIN TO FORM A LOW PRESSURE
OVER THE CENTRAL ALEUTIANS BY MONDAY NIGHT. THIS LOW WILL STRENGTHEN
AS IT MOVES ACROSS THE SOUTHERN BERING AND ALEUTIAN CHAIN...AND
BECOME THE NEW DOMINANT LOW OVER THE SAINT MATTHEW LOW BY LATE
TUESDAY. THIS LOW IS EXPECTED TO MOVE INTO THE GULF OF ALASKA FOR
THE MIDDLE TO LATTER PART OF THE WEEK...WITH A STRONG RIDGE OF HIGH
PRESSURE BUILDING OVER THE ALEUTIANS/BERING SEA.

...MODELS...
MODELS ARE IN GOOD AGREEMENT OVER THE EAST...WITH DISAGREEMENTS
SHOWING UP IN THE WEST OVER THE BERING AND ALEUTIANS. NONE OF THE
MODELS AGREE PERFECTLY REGARDING THE EVOLUTION AND STRENGTH OF THE
NORTHERN AND SOUTHERN BERING LOWS...THOUGH THEY ALL...WITH THE
EXCEPTION OF THE NAM/WRF...HAVE THE SAME GENERAL IDEA OF THE
NORTHERN BERING LOW WEAKENING TUESDAY WITH THE SOUTHERN BERING LOW
BECOMING DOMINANT AROUND LATE TUESDAY. GFS HAS BEEN FAIRLY
CONSISTENT...SO WILL FAVOR IT OVER THE WEST WITH THIS FORECAST
PACKAGE. NAM/WRF...AS MENTIONED ABOVE...SEEMS TO BE THE ODDBALL MODEL
AT THIS TIME ESPECIALLY OVER THE LATTER PERIODS...WITH IT HAVING THE
LOW MUCH FURTHER NORTH ON TUESDAY THAN THE OTHER MODELS...AND ALSO
MUCH DEEPER.

...SOUTHCENTRAL ALASKA/KODIAK ISLAND FORECAST...
SCREAMING MESSAGE FOR SOUTHCENTRAL ALASKA IS THE DRYING TREND...WITH
SEVERAL CONSECUTIVE DAYS OF DRY WEATHER AND PARTLY CLOUDY SKIES
EXPECTED FOR A CHANGE. THERE ARE STILL SOME SHOWERS THIS MORNING
ALONG THE NORTHERN GULF COAST AND NEAR KODIAK ISLAND.
HOWEVER...THESE ARE EXPECTED TO TAPER OFF BY LATE TODAY AS THE LOW
MOVES EAST AND CLOSER TO THE PANHANDLE. INTERIOR SOUTHCENTRAL ALASKA
IS EXPECTED TO BE GENERALLY DRY THROUGH TUESDAY NIGHT WITH AN UPPER
LEVEL RIDGE OVER THE AREA AND OFFSHORE FLOW. THERE MAY BE A FEW
AFTERNOON SHOWERS TODAY AND MONDAY WITH THE DAYTIME HEATING AND HELP
OF THE MOIST SOILS...BUT NO SIGNIFICANT RAINFALL IS EXPECTED. THE
RAINY PATTERN IS EXPECTED TO RETURN TUESDAY NIGHT FOR KODIAK...AND
FOR WEDNESDAY OVER MOST OTHER PARTS OF SOUTHCENTRAL ALASKA...AS A
LOW MOVES INTO THE GULF OF ALASKA. AT THIS POINT...IT IS STILL HARD
TO TELL IF THE WET WEATHER WILL LAST INTO NEXT WEEKEND.

...SOUTHWEST MAINLAND ALASKA FORECAST...
A RIDGE OF HIGH PRESSURE WILL AMPLIFY OVER SOUTHWEST MAINLAND ALASKA
TODAY WITH MOSTLY DRY CONDITIONS EXPECTED. A SHORTWAVE WILL MOVE OUT
WELL AHEAD OF THE LOW TONIGHT AND MONDAY...BRINGING SOME RAIN TO
COASTAL AREAS. HOWEVER...THIS SHORTWAVE WILL BE WEAKENING AS IT
MOVES INTO THE RIDGE...AND RAIN IS NOT EXPECTED TO BE TERRIBLY HEAVY
NOR IS IT EXPECTED TO MAKE IT FAR INLAND. QUIET WEATHER WILL RESUME
FOR LATE MONDAY THROUGH MIDDAY TUESDAY. THEN WET WEATHER WILL RETURN
IN EARNEST FOR THE SOUTHWEST MAINLAND LATE TUESDAY INTO WEDNESDAY
WITH AN AREA OF LOW PRESSURE MOVING EAST THROUGH BRISTOL BAY AND TO
THE ALASKA PENINSULA. CONDITIONS ARE EXPECTED TO DRY OUT BY LATE
THURSDAY AS THE LOW MOVES INTO THE GULF OF ALASKA AND AWAY FROM
SOUTHWEST ALASKA.

...ALEUTIAN ISLANDS/BERING SEA FORECAST...
A PERIOD OF RAINY WEATHER IS IN STORE WITH A SERIES OF SHORTWAVES IN
STRONG WESTERLY FLOW. EVENTUALLY A WELL DEFINED SURFACE LOW PRESSURE
WILL FORM BY MONDAY NIGHT OR TUESDAY AND WILL RIDE EAST ALONG THE
BERING SIDE OF THE ALEUTIANS. THERE IS THE LIKELIHOOD OF GALES NEAR
THIS LOW. AS THE LOW MOVES EAST...A STRONG RIDGE WILL FORM OVER THE
CENTRAL AND WESTERN ALEUTIANS AROUND THE MIDDLE OF THE WEEK. THIS
WILL MEAN AN END TO THE RAIN...BUT A RETURN TO ABUNDANT FOG...FOR
THE MIDDLE AND LATTER PART OF THE WEEK.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...NONE.
FIRE WEATHER...NONE.

FOISY AUG 06