Small Craft Advisory 415, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
600 AM ADT THU MAY 04 2006

.DISCUSSION...
PROGRESSIVE PATTERN CONTINUES. BROAD LOW OVER THE NORTHERN GULF EARLY
THIS MORNING WITH STRONGEST WINDS ALONG THE BACKSIDE OF THE OCCLUDED
FRONT THAT MOVED OVER SOUTHCENTRAL OVERNIGHT. SECOND LOW AT 976 MB IS
LOCATED SOUTH OF THE WESTERN ALEUTIANS WITH A FRONT EXTENDING EAST
ACROSS THE SOUTHERN BERING SEA TOWARD DUTCH HARBOR. MODELS INITIALIZE
WELL WITH PRIMARY FEATURES AND ARE IN REMARKABLE AGREEMENT THROUGH 60
HOURS. SOME OF THE DETAILS SURROUNDING A DEVELOPING TRIPLE POINT LOW
ALONG THE CENTRAL ALEUTIANS SEEM TO BE BETTER REPRESENTED WITH THE
ETA...ESPECIALLY ONCE THE LOW NEARS BRISTOL BAY AND SOME OF THE
COMPLEX TERRAIN BEGIN TO INTERACT WITH THE SYSTEM.

UPPER AIR...ANCHOR UPPER LOW ENTRENCHED OVER THE EASTERN BERING SEA.
TWO CUTOFF LOWS ROTATING AROUND ITS PERIPHERY. BOTH LOWS WILL BE
ABSORBED OVER THE NEXT 24 HOURS HELPING SOLIDIFY ITS DOMINANCE OVER
BRISTOL BAY. 180 KNOT JET MAX NEAR THE 47TH PARALLEL SOUTH OF THE
ANCHOR LOW WILL SHIFT EASTWARD INTO THE SOUTHERN GULF BY THE WEEKEND
AND BE REPLACED BY ANOTHER JET MAX BY EARLY NEXT WEEK.

SOUTHCENTRAL SURFACE...IMPRESSIVE FROPA OVERNIGHT WITH WETTING RAIN
OVER MUCH OF SOUTHCENTRAL. STILL ABUNDANT MOISTURE BEHIND THE MAIN
FRONT WITH BROAD LOW PRESSURE OVER THE NORTHERN GULF SO COASTAL AREAS
WILL REMAIN UNDER THE GUN TODAY. WINDS WILL RELAX DURING THE DAY ONLY
TO RETURN AGAIN OVER NIGHT WITH A TIGHTENING PRESSURE GRADIENT
ASSOCIATED WITH THE NEXT OCCLUSION. TODAY...THE WEAKENING PRESSURE
GRADIENT AND ABUNDANT LOW LEVEL MOISTURE WILL KEEP AT LEAST A CHANCE
OF RAIN OVER NORMALLY DOWNSLOPED AREAS LIKE THE ANCHORAGE BOWL AND
THE WESTERN KENAI. THE NEXT SYSTEM APPROACHES TONIGHT WITH MORE WINDS
WHICH SHOULD BRING AN END TO THE RAIN IN ANCHORAGE UNTIL SATURDAY
EVENING WHEN A SHORTWAVE TROF AXIS ROTATES THROUGH AND SHIFTS THE LOW
LEVEL WINDS TO THE SOUTH.

SOUTHWEST SURFACE...WET THEME CONTINUES TO THE WEST OF THE ALASKA
RANGE WHERE UPPER LOW DOMINATES THE REGION. THE REMNANTS OF THE
SOUTHCENTRAL FRONT WILL MOVE ACCROSS THE ALASKA RANGE AND BRING A
DECENT CHANCE OF RAIN TO THE KUSKOKWIM VALLEY TODAY. RAIN AND SNOW
ALREADY FALLING THIS MORNING OVER ZONE 161 IN SOUTHWEST ALASKA. THERE
WILL BE A BRIEF BREAK BETWEEN THE TWO SYSTEMS THIS EVENING BEFORE THE
NEXT LOW APPROACHES FROM THE SOUTHWEST WHICH IS A MUCH MORE FAVORABLE
SCENARIO FOR PRECIPITATION. THE DEVELOPING TRIPLE POINT LOW OVER THE
CENTRAL ALEUTIANS WILL MOVE TOWARD BRISTOL BAY AND EVENTUALLY OVER
THE SOUTHERN KUSKOKWIM VALLEY BY FRIDAY NIGHT. COLD AIR ADVECTION IS
ESTABLISHED BEHIND THE LOW OVER MOST OF THE BERING SEA BY THURSDAY
EVENING AND IS SUSTAINED THROUGH SUNDAY MORNING BEFORE THE NEXT
SYSTEM APPROACHES THE WESTERN AND CENTRAL ALEUTIANS.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...STORMS 175 176. GALES 172.
FIRE WEATHER...NONE.

AB MAY 06