Small Craft Advisory 468, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
200 PM ADT SUN MAY 21 2006

.DISCUSSION...

UPPER LEVELS...RIDGE OVER THE CENTRAL BERING SEA WITH A LOW JUST
SOUTH OF THE GULF AND ANOTHER LOW OVER THE KAMCHATKA PENINSULA. WEAK
TROUGH OVER EASTERN ALASKA. THE WEAK TROUGH IS PUSHED OUT BY THE
RIDGE BUILDING INTO THE INTERIOR TONIGHT. RIDGE TO REMAIN OVER THE
BERING SEA THROUGH FRIDAY. HOWEVER...A SHORT WAVE TROUGH WILL KNOCK
DOWN THE HIGH A BIT BEGINNING THURSDAY AND MOVE THE AXIS OVER WESTERN
ALASKA. THIS WAVE IN COMBINATION WITH AN APPROACHING TROUGH FROM
CENTRAL ASIA WILL LIFT THE KAMCHATKA LOW INTO EASTERN SIBERIA. IN THE
MEANTIME...THE LOW IN THE GULF SLOWLY WEAKENS THROUGH THURSDAY THEN
MOVES TOWARD THE PACIFIC NORTHWEST.

MODEL ANALYSIS...MODELS INITIALIZED WELL AND SHOW GOOD CONSISTENCY.
THE ONLY DIFFERENCES NOTED ARE THE EXACTNESS OF A LOW TRACKING NORTH
OVER THE WESTERN ALEUTIAN CHAIN TUESDAY AND THE EXACT CENTER OF THE
LOW IN THE GULF ON WEDNESDAY. WILL GO WITH THE GFS SOLUTION FOR NOW.

EAST OF THE ALASKA RANGE...WEAK UPPER LEVEL TROUGH MOVING SOUTH OVER
SOUTH CENTRAL. EXPECT CLEARING THIS AFTERNOON AND EVENING. HIGH TO
BUILD OVER LAND TONIGHT AS WELL. HIGH PRESSURE TO DOMINATE INTO
FRIDAY WITH DRIER AND WARMER CONDITIONS. AS THE FRONT SIDE OF THE
RIDGE MOVES INLAND TONIGHT...FLOW ALOFT FROM THE NORTH WILL PICK UP.
COMBINED WITH THE SURFACE LOW IN THE SOUTHERN GULF...MODERATE TO
STRONG NORTHERLY WINDS AT THE SURFACE WILL BE PRESENT MONDAY OVER
SOUTHCENTRAL AND SURROUNDING WATERS. AS THE LOW WEAKENS IN THE
GULF...SO TOO WILL THE POTENTIAL OF THE WIND SPEEDS. DRY CONDITIONS
WILL PERSIST.

WEST OF THE ALASKA RANGE...TIGHT PRESSURE GRADIENT OVER WESTERN
ALASKA AND ALASKA PENINSULA FROM A LOW IN THE GULF AND HIGH PRESSURE
OVER THE CENTRAL ALEUTIAN ISLANDS. WITH SUPPORT ALOFT...WINDS HAVE
MAINTAINED 40-50 MPH WITH GUSTS AROUND 60 MPH. GRADIENT AND JET
SUPPORT TO DECREASE QUICKLY TUESDAY. UNTIL THEN...EXPECT MODERATE TO
STRONG NORTHWEST WINDS ACROSS THIS AREA. HIGH PRESSURE TO REMAIN OVER
THE CENTRAL ALEUTIAN CHAIN THROUGH THE WEEK. A LOW IS ANTICIPATED TO
MOVE NORTH OVER THE WESTERN ALEUTIAN CHAIN MONDAY AND TO THE
KAMCHATKA LOW BY TUESDAY NIGHT. RAIN AND GALE FORCE WINDS TO CROSS
THIS AREA AS A RESULT MONDAY AND TUESDAY. STRATUS TO REMAIN OVER THE
BERING SEA WITH HIGH PRESSURE THE DOMINANT FEATURE. SOME SUNNY BREAKS
ARE POSSIBLE THOUGH. IN ADDITION...SHORT WAVE TROUGH MOVING SOUTH
ALONG THE ALEUTIAN RANGE TODAY...WILL KEEP SHOWER ACTIVITY ALONG
THERE TODAY. DRY CONDITIONS TO PERSIST OVER SOUTHWEST ALASKA TO THE
CENTRAL ALEUTIANS THROUGH FRIDAY.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...GALE 130 132 150 155 165 176
FIRE WEATHER...FIRE WEATHER WATCH ZONE 111 141 AND 145 MON AFTN AND
EVE.

JN MAY 06