Small Craft Advisory 609, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
217 PM AKDT TUE AUG 12 2014

.ANALYSIS AND UPPER LEVELS...
THE MAIN WEATHER PRODUCER FOR THE SOUTHERN HALF OF THE STATE AND
THE BERING IS A LOW OVER THE CENTRAL ALEUTIANS. THE FRONT
ASSOCIATED WITH THIS LOW IS PUSHING NORTH THROUGH THE GULF AND
WILL MAKE IT OVER THE SOUTHCENTRAL THIS EVENING. THE LOW IS ALSO
BRINGING UP MOISTURE FROM THE PACIFIC WHICH WILL LEAD TO
WIDESPREAD RAIN THROUGH MOST THE SOUTHWEST...SOUTHCENTRAL AND
NORTHERN GULF COAST.

&&

.MODEL DISCUSSION...
THE MODELS ARE IN DECENT AGREEMENT EARLY ON WITH THE MAJOR
FEATURES...HOWEVER AS THEY MOVE INTO THE MID TERM DISCREPANCIES
START TO FORM. THE 12Z GFS KEEPS THE LOW MOVING ACROSS THE
ALEUTIANS TO THE SOUTH WHILE THE 12Z NAM IS SLOWER THAN THE OTHER
MODELS WITH THE SAME LOW. THE 18Z RUNS OF THE NAM AND GFS ARE
MOVING CLOSER TO THE EC SOLUTION. THE EC AND GEM HAVE MORE OF A
MEDIAN POSITION AND ARE ALSO DOING BETTER WITH RUN TO RUN
CONSISTENCY.

&&

.SHORT TERM FORECAST...

SOUTHCENTRAL ALASKA...A FRONT WILL MOVE THROUGH THE SOUTHCENTRAL
THIS EVENING AND THROUGH MUCH OF THE NIGHT WHICH WILL BRING RAIN
AND STRONGER WINDS THROUGHOUT THE AREA INCLUDING THE NORTH GULF
COAST. THINGS WILL CALM DOWN SOME WEDNESDAY BUT INTERMITTENT RAIN
WILL REMAIN UNTIL ANOTHER TROUGH BRINGS STEADY RAIN AGAIN ON
THURSDAY.

SOUTHWEST ALASKA...THE FRONT IS MOVING THROUGH THE BRISTOL BAY
AREA AND IS BRINGING RAIN WITH IT. IT WILL CONTINUE TO PUSH NORTH
INTO THE EVENING SPREADING RAIN THROUGHOUT ALL OF THE SOUTHWEST.
BEHIND THE FRONT SOUTHERLY FLOW WILL BRING CONTINUED RAIN TO THE
AREA THROUGH THE REST OF THE WEEK.

BERING SEA/ALEUTIANS...THE MAIN SURFACE LOW IS MOVING ACROSS THE
ALEUTIANS AND INTO THE PACIFIC WHERE IT WILL TAKE A MORE EASTERLY
TRACK WEDNESDAY. BEHIND THE LOW NORTHERLY FLOW WILL DOMINATE THE
CENTRAL AND WESTERN ALEUTIANS CLEARING UP MOST OF THE
RAIN...EXCEPT FOR A FEW ISOLATED SHOWERS. FOR THE EASTERN
ALEUTIANS AND EASTERN PARTS OF THE BERING RAIN WILL REMAIN THROUGH
MUCH OF THE WEEK WITH WEAK FLOW OVER THE AREA.

&&

.LONG TERM FORECAST...
RAIN LOOKS TO REMAIN IN THE FORECAST FOR MUCH OF THE SOUTHERN
MAINLAND THROUGH EARLY NEXT WEEK AS MODELS HAVE COME INTO BETTER
AGREEMENT WITH RESPECT TO THE NEXT LOW PRESSURE SYSTEM APPROACHING
THE GULF OF ALASKA THIS WEEKEND. THE UPPER LOW WILL BE LOCATED IN
THE VICINITY OF THE ALASKA PENINSULA LATE FRIDAY AND THEN MOVE
NORTHEASTWARD ACROSS KODIAK ISLAND AND TOWARDS THE NORTHERN GULF
COAST BY SUNDAY AFTERNOON AS IT GRADUALLY WEAKENS INTO AN OPEN
TROUGH. THIS WILL GENERALLY RESULT IN STEADY RAIN ALONG THE GULF
COAST WITH SHOWERS FARTHER INLAND. MEANWHILE...THE BERING WILL SEE
A BIT OF A BREAK IN THE PRECIPITATION AS THE LOW DEPARTS AND IS
THEN REPLACED BY WEAK SURFACE RIDGING FOR THE WEEKEND. HOWEVER...
SHOWERS WILL REMAIN A POSSIBILITY INTO NEXT WEEK AS THE LONGWAVE
TROUGH CENTERED OVER THE EASTERN BERING IS REINFORCED BY ANOTHER
SHORTWAVE DROPPING OUT OF EASTERN RUSSIA.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALE WARNING...119 125.
FIRE WEATHER...NONE.

&&

AUG 14