Small Craft Advisory 493, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
200 PM AKDT SUN JUL 17 2011

.MODEL DISCUSSION...MODELS ARE IN GOOD AGREEMENT FOR THE SHORT TERM.
GOING WITH THE NAM FOR ITS BETTER DETAIL. AS WE TRANSITION INTO THE
MID TERM...WE ARE TRENDING TOWARDS THE EC OUT EAST AS IT IS MOVING
THINGS SLIGHTLY FASTER THAN THE NAM. CONSISTENCY IS STILL POOR IN THE
LONG RANGE SO WE ARE TRENDING MORE TOWARD HPC GUIDANCE.

.ANALYSIS AND UPPER LEVELS...THE MAIN FEATURE OVER THE STATE IS THE
UPPER LEVEL LOW JUST SOUTH OF THE SEWARD PENINSULA. IT REMAINS ON ITS
SLOW TRACK TO THE SOUTHEAST AND WILL MAKE IT OVER THE GULF BY TUESDAY
MORNING. THIS LOW WILL ALSO PUSH A TROUGH OVER THE SOUTHCENTRAL
TONIGHT. TO THE WEST RIDGING IS BUILDING IN OVER THE CENTRAL
ALEUTIANS OUT OF A NORTH PACIFIC HIGH. BUT BY TUESDAY MORNING THIS
RIDGE WILL BE GONE AND A NEW LOW WILL MOVE INTO THE SOUTHERN BERING
FROM THE WEST.

.SHORT TERM FORECAST...FOR THE EAST...AS THE TROUGH MOVES OVER THE
SOUTHCENTRAL WE WILL SEE RAIN DEVELOP ACROSS THE AREA THIS
EVENING AND CONTINUE INTO TOMORROW MORNING. BEHIND THIS SYSTEM...
ISOLATED SHOWERS WILL LINGER FOR THE NEXT SEVERAL DAYS. SIMILAR TO
YESTERDAY...THERE IS A CHANCE FOR ISOLATED THUNDERSTORMS IN THE
SUSITNA AND MATANUSKA VALLEYS AND THE COPPER RIVER BASIN TODAY AND
TOMORROW.

.FOR THE WEST...WITH THE CONTINUED PATTERN OF SHORTWAVES MOVING
ACROSS THE BERING AND INTO THE WESTERN PART OF THE STATE...RAIN
SHOWERS WILL BE A CONSTANT FACTOR FOR MOST OF THE WEEK. THE RIDGE
BUILDING OVER THE CENTRAL ALEUTIANS WILL REDUCE THE CHANCE FOR RAIN
BUT WILL BRING FOG TO THE CENTRAL AND EASTERN ALEUTIANS AND PORTIONS
OF SOUTHWEST ALASKA AS IT PROGRESSES EASTWARD.

.LONG TERM FORECAST...THE NORTH PACIFIC HIGH WILL KEEP FLOW OVER THE
STATE ZONAL FOR THE MAJORITY OF THE WEEK KEEPING OUR WEATHER PATTERN
ACTIVE WITH MULTIPLE SHORTWAVES MOVING ACROSS THE AREA.

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

DWK JUL 11