Gale Warning 653, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
200 PM AKDT MON SEP 13 2010

.MODEL DISCUSSION...MORNING MODELS REMAIN IN EXCELLENT AGREEMENT
THROUGH DAYS 5-7...AND SHOW GOOD CONTINUITY DEPICTING 500 MB
RIDGE/OMEGA-BLOCKING PATTERN REMAINING CENTERED DIRECTLY OVER
MAINLAND AK AND SOUTH THROUGH THE GULF THROUGH DAY 7. BOTH GFS AND
ECMWF SHOW WEAK SHORT-WAVES TEMPORARILY FLATTENING THE TOP OF
THE UPPER RIDGE OVER NORTHERN THIRD OF AK THIS THU/FRI...WITH RIDGE
REBOUNDING AGAIN OVER THE WEEKEND.

.ANALYSIS AND UPPER LEVELS...WITH STRONG UPPER/SURFACE RIDGING
IN PLACE OVER MAINLAND ALASKA...AND VERY LIGHT GENERAL WIND FLOW
OVER ALL MAINLAND COASTAL AREAS...FOG WAS WIDESPREAD THIS MORNING
BUT SHALLOW. ALL AREAS WERE ABLE TO BURN OFF TODAY BY 1PM WITH THE
STILL EFFECTIVE MID-SEPT. SUN...WITH THE EXCEPTION OF BETHEL AND
KODIAK. AREAS AROUND THE YUKON-KUSKOKWIM DELTA ARE SLOWER TO BURN
OFF TODAY AS SOME STRATUS IS ADVECTING N FROM BRISTOL BAY AND ERN
BERING IN SOUTHERLY FLOW AHEAD OF WEAKENING N-S ORIENTED FRONT THAT
STRETCHES S FROM ST LAWRENCE ISLAND TO COLD BAY.

.SHORT TERM FORECAST...CLEAR AND COOL NIGHT AGAIN ALL INLAND AREAS
UNDER VERY DRY...STILL AIRMASS WITH ONLY PATCHY GROUND FOG EXPECTED
USUAL LOW-LYING MOIST POCKETS. WITH VERY LITTLE CHANGE IN SURFACE
PRESSURE PATTERNS TONIGHT...EXPECT FOG...LOCALLY DENSE IN ALL COASTAL
AREAS TO RE-FORM BETWEEN MIDNIGHT AND 4AM...AND PERSIST UNTIL EARLY
AFTERNOON TOMORROW. INLAND AREAS WILL EXPERIENCE ANOTHER SUMMER-LIKE
DAY TOMORROW AND WED. WITH TEMPS. REACHING INTO THE 60SF. FREE-AIR
FREEZING LEVELS WILL BE UP TO 10-12 THOUSAND FEET BY WED...BUT WEAKER
SUN AND SHORTER DAYS WILL KEEP TEMPS. FROM EXCEEDING 70F MOST AREAS.
WEAKENING ERN BERING FRONT WILL REMAIN STATIONARY TONIGHT AND EARLY
TUE FROM NUNIVAK ISLAND S TO COLD BAY...AND WILL DISSIPATE...AS IT
MOVES INTO BLOCKING RIDGE. SO AREAS OF LIGHT RAIN BETWEEN COLD BAY
AND SAND POINT WILL GRADUALLY DIMINISH TONIGHT...AS WELL AS THE MINIMUM
GALE AND SMALL CRAFT ADVISORY-LEVEL WINDS.

.LONG TERM FORECAST...WITH UPPER RIDGE REMAINING IN PLACE THROUGH
THE WEEK OVER THE MAINLAND...DRY AND CLEAR WEATHER WITH ABOVE-AVERAGE
DAYTIME HIGHS EXPECTED INTO THE WEEKEND. WITH NO SIGNIFICANT LOWS
IN THE GULF OF AK...LIGHT WIND FLOW OVER THE MAINLAND AND GULF COASTAL
AREAS ALSO TO CONTINUE. AREAS OF MORNING FOG WILL ALSO CONTINUE NEXT
SEVERAL DAYS AS WELL ON BERING AND GULF COASTS. WITH SUCH GOOD MODEL
AGREEMENT AND CONTINUITY...HIGH CONFIDENCE THAT A 1000 MB NORTH PACIFIC
LOW CURRENTLY NEAR 160E/40N WILL DEEPEN TO AROUND 977 MB 18Z THU NEAR
48N/178E...THEN FILL RAPIDLY FRI AS IT WOBBLES JUST A LITTLE FURTHER E
TO NEAR 48N/177W. FRONT AHEAD OF THIS LOW WILL BRING SMALL CRAFT ADVISORY
TO MINIMUM GALE FORCE WINDS TO WESTERN AND CENTRAL ALEUTIANS...AND
RAIN...LATE TOMORROW THROUGH THU...DISSIPATING FRI OVER EASTERN ALEUTIANS.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...GALE WARNING 170 180 TONIGHT
FIRE WEATHER...NONE

MAR SEP 10