Small Craft Advisory 429, NWS Anchorage, AK

AREA FORECAST DISCUSSION
SOUTHCENTRAL AND SOUTHWEST ALASKA
500 PM ADT THU MAY 10 2007

.ANALYSIS AND UPPER LEVELS...
THERE IS A BROAD TROUGH AND UPPER LOW MOVING OVER THE GULF OF ALASKA.
SECOND LARGE UPPER LOW WILL DROP INTO THE WESTERN BERING SEA FROM
EASTERN RUSSIA. A GOOD HIGH PRESSURE RIDGE WILL BUILD INTO THE
CENTRAL BERING SEA BETWEEN THE TWO LOWS. AT THE SURFACE AN AREA OF
LOW PRESSURE SOUTH OF THE GULF WILL DRIFT EASTWARD AND DISSIPATE
SATURDAY MORNING. THE LOW OVER THE BERING WILL DROP IN THE
SOUTHWESTERN GULF BY SATURDAY. THE ASSOCIATED FRONT IN MOVING ALONG
THE CENTRAL ALEUTIANS TODAY. WARM ADVECTION OUT AHEAD OF THIS FRONT
IS BRINGING RAIN AND FOG TO THE PRIBILOFS AND ALASKA PENINSULA. AS
THE LOW ENTERS THE SOUTHWEST GULF ON SATURDAY A STRONG HIGH PRESSURE
RIDGE WILL FORM ALONG THE SOUTHCENTRAL GULF.

.MODEL DISCUSSION...
THE MODEL ARE IN GOOD AGREEMENT THROUGH SATURDAY. THEN THERE IS SOME
DIFFERENCE ON THE HANDLING OF THE LOW MOVING SOUTHEAST OF THE ALASKA
PENINSULA SATURDAY. GFS IS A BIT DEEPER AND AND NOT AS FAST AS THE
NAM AND MORE IN LINE WITH THE UKMET. THE PREFERRED MODEL IT THE GFS
TODAY WHICH ALSO BRINGS IN THE STRONGER RIDGING ALONG THE COAST ON
SATURDAY.  PLUS THE FACT THAT THE LOW IN THE WESTERN GULF HAS A JET
STREAK DOWNSTREAM WHICH WILL ALLOW IT TO DIG IN.

.SHORT TERM FORECAST...
CONVECTIVE SHOWERS WILL CONTINUE THIS EVENING FOR MUCH OF
SOUTHCENTRAL THIS EVENING UNDER WEAK FLOW ALOFT. ISOLATED
THUNDERSTORMS ARE ALSO POSSIBLE THIS EVENING ALONG TALKEETNA
MOUNTAINS AND ALASKA RANGE AND DOWN INTO THE MATSU VALLEY.  SHOWERS
WILL ALSO CONTINUE ACROSS THE KUSKOKWIM DELTA AND BRISTOL BAY BY
TONIGHT AS A THE REMANENTS OF A SHORTWAVE PASSES THROUGH SOUTHWEST.
OUT WEST RAIN AND FOG WILL CONTINUE AHEAD OF THE FRONT WITH SHOWERS
BEHIND IT.

.LONG TERM FORECAST...
FRIDAY HAS THE THERMAL TROUHGH SHIFTING TO THE EAST OVER THE COPPER
RIVER EASTWARD. THUNDERSTORM ACTIVITY SHOULD BE ISOLATED MAINLY ALONG
THE NORTHERN PART OF THE COPPER RIVER ZONE. THE REST OF SOUTHCENTRAL
SHOULD SEE MOSTLY CLOUDY SKIES WITH ISOLATED SHOWERS INTO  THE
WEEKEND. WITH THE RIDGED DEVELOPING ALONG THE COAST SATURDAY WE CAN
EXPECT SOME STRONG TURNAGAIN WINDS. THE CONVECTION ACROSS THE
KUSKOKWIM VALLEY AND BRISTOL BAY SHOULD BE MUCH DROP OFF FRIDAY BUT
PICK UP AGAIN SATURDAY AS A GOOD SHORT WAVE DROPS DOWN FROM THE
NORTHWEST.  WITH THE HIGH PRESSURE OVER MUCH OF THE BERING THE
CONDITIONS THERE WILL CONTINUE TO CLOUDY AND PROBABLY ON THE DRY
SIDE.

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

MAY 07