Gale Warning 703, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
415 PM AKDT FRI OCT 18 2013

.ANALYSIS AND UPPER LEVELS...
THE MAIN FEATURE OF INTEREST THIS AFTERNOON REMAINS THE BROAD UPPER
LEVEL TROUGH ENCOMPASSING THE BERING SEA...WITH A 968 MB SURFACE LOW
PUSHING EASTWARD BETWEEN THE EASTERN ALEUTIANS AND THE PRIBILOF
ISLANDS. THIS SYSTEM CONTINUES TO BRING GALE FORCE WINDS TO MUCH OF
THE BERING...WITH AN AREA OF STORM FORCE WINDS OVER THE CENTRAL AND
EASTERN ALEUTIANS ON THE SOUTH SIDE OF THE LOW. AN ASSOCIATED FRONT
IS BEGINNING TO MOVE INLAND OVER SOUTHWEST ALASKA...ACCOMPANIED BY
STRONG SOUTHEASTERLY WINDS ALONG THE COAST AND CONTINUED RAIN FOR THE
SOUTHWEST MAINLAND. ANOTHER FRONT IS MAKING ITS WAY INLAND OVER THE
NORTHERN GULF COAST...WITH SCATTERED SHOWERS AND GUSTY WINDS
CONTINUING OVER MUCH OF SOUTHCENTRAL ALASKA.

.MODEL DISCUSSION...
MODELS REMAIN IN GOOD SYNOPTIC AGREEMENT THROUGH THE SHORT
TERM...SHOWING GOOD CONSISTENCY IN CURVING THE BERING LOW NORTHWARD
TONIGHT TO A POSITION NEAR NUNIVAK ISLAND BY SATURDAY AFTERNOON. THE
LOW WILL THEN CONTINUE TO GRADUALLY WEAKEN AS IT MOVES INTO THE
NORTHERN BERING IN THE VICINITY OF SAINT LAWRENCE ISLAND ON SUNDAY.
THIS WILL KEEP MUCH OF THE MAINLAND IN BROAD SOUTHERLY FLOW THROUGH
THE WEEKEND AS A STOUT DOWNSTREAM RIDGE REMAINS ENTRENCHED OVER THE
NORTHEAST PACIFIC AND WESTERN CANADA. THERE IS ALSO GOOD AGREEMENT ON
THE DEVELOPMENT OF A WEAK TRIPLE POINT FEATURE OVER THE WESTERN GULF
LATE TONIGHT THAT WILL THEN TRACK INLAND OVER SOUTHCENTRAL AK.
GENERALLY UTILIZED THE NAM FOR INCREASED DETAIL GIVEN THE GOOD
OVERALL AGREEMENT.

.SHORT TERM FORECAST...
SOUTHCENTRAL ALASKA...
MORE WIND AND RAIN IS IN STORE FOR THIS WEEKEND AS ANOTHER FRONT AND
A WEAK TRIPLE POINT FEATURE TRACK INLAND LATE TONIGHT AND EARLY
TOMORROW. WINDS WILL ONCE AGAIN INCREASE ALONG TURNAGAIN ARM AND
HIGHER ELEVATIONS TONIGHT AS THE PRESSURE GRADIENT STRENGTHENS WITH
THE BERING LOW TRACKING NORTHWARD AND THE FRONT MOVING THROUGH. THE
TRIPLE POINT LOOKS TO DEVELOP LATE TONIGHT EAST OF KODIAK ISLAND AND
TRACK QUICKLY TOWARDS PRINCE WILLIAM SOUND...WHICH WILL HELP TO
ENHANCE THE DOWN INLET GRADIENT AND THUS KEEP THE TURNAGAIN ARM WINDS
OUT OF THE REMAINDER OF THE ANCHORAGE BOWL. WINDS WILL GRADUALLY
TREND DOWNWARD THROUGH THE WEEKEND AS THE LOW MOVES INTO THE NORTHERN
BERING AND WEAKENS. THE FRONT AND TRIPLE POINT FEATURE WILL ALSO
BRING WIDESPREAD RAIN TO SOUTHCENTRAL THROUGH THE DAY ON SATURDAY.
ONSHORE FLOW WILL THEN KEEP RAIN IN THE FORECAST INTO EARLY NEXT
WEEK...WITH GENERALLY STEADIER RAIN ALONG THE GULF COAST AND SHOWERS
INLAND.

SOUTHWEST ALASKA...
RAINY AND WINDY CONDITIONS WILL CONTINUE OVER THE SOUTHWEST MAINLAND
THROUGH THE WEEKEND AS THE LOW IN THE EASTERN BERING NEARS NUNIVAK
ISLAND AND REMAINS JUST OFF THE COAST...KEEPING MOST OF THE AREA IN
ONSHORE FLOW FOR THE NEXT SEVERAL DAYS. STRONG SOUTHEASTERLY WINDS
ALONG THE IMMEDIATE COAST WILL BEGIN TO SUBSIDE SATURDAY AFTERNOON AS
THE LOW BEGINS TO WEAKEN AND MOVE FURTHER TO THE NORTH.

ALEUTIANS/BERING SEA...
RAIN AND GALE FORCE WINDS WILL CONTINUE TO IMPACT MUCH OF THE BERING
SEA THROUGH SATURDAY AS THE LOW PROGRESSES THROUGH THE EASTERN
BERING. CONDITIONS WILL BEGIN TO IMPROVE SOMEWHAT ON SUNDAY FROM WEST
TO EAST ACROSS THE ALEUTIANS AS THE LOW MOVES FURTHER TO THE NORTH
AND BEGINS TO WEAKEN...BUT RAIN AND GUSTY WINDS WILL GENERALLY REMAIN
IN THE FORECAST INTO THE BEGINNING OF THE WEEK.

.LONG TERM FORECAST...
MODELS SUGGEST AN AMPLIFIED PATTERN WILL CONTINUE INTO NEXT WEEK WITH
A BROAD UPPER LEVEL TROUGH OVER THE BERING AND A STRONG RIDGE
REMAINING OVER WESTERN CANADA. THIS WILL LEAD TO CONTINUED ONSHORE
FLOW OVER THE SOUTHERN MAINLAND...KEEPING A CHANCE OF RAIN IN THE
FORECAST INTO NEXT WEEK FOR MUCH OF THE AREA.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE
MARINE...GALE WARNING 119 130 131 150 155 160 165 170 172 173 174
                      175 176 177 180 185
FIRE WEATHER...NONE

CB OCT 13