Small Craft Advisory 833, NWS Anchorage, AK

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
200 PM AKDT THU OCT 24 2013

.ANALYSIS AND UPPER LEVELS...
THERE IS A STRONG LOW IN THE EASTERN BERING SEA WITH A FRONT
STRETCHING ACROSS THE SOUTHERN ALASKA MAINLAND THEN SOUTH ACROSS THE
GULF OF ALASKA. THERE IS ANOTHER LOW SOUTH OF THE WESTERN ALEUTIANS
THAT IS MOVING EAST. A RIDGE OF HIGH PRESSURE IS ALONG THE BRITISH
COLUMBIA WEST COAST.

.MODEL DISCUSSION...
THE NUMERICAL MODELS ARE IN FAIRLY GOOD AGREEMENT THROUGH ABOUT 60
HOURS (SATURDAY AFTERNOON). AFTER THAT THERE ARE TIMING/STRENGTH
DIFFERENCES WITH FEATURES ASSOCIATED WITH A LOW OVER THE ALEUTIANS
AND ITS ASSOCIATED FRONTS AND SHORT-WAVE TROUGHS. THE DIFFERENCES
FOR THE MOST PART ARE NOT LARGE...BUT WOULD HAVE SOME CONSEQUENCES
FOR SENSIBLE WEATHER OVER THE EASTERN BERING/ALEUTIANS AND THE
SOUTHERN MAINLAND. THEREFORE CONFIDENCE IS HIGHER THAN NORMAL
THROUGH SATURDAY...THEN NEAR TO BELOW NORMAL AFTER THAT.

.SHORT TERM FORECAST...
FOR SOUTH CENTRAL ALASKA...SHOWERS AND LOCAL WINDS WILL CONTINUE
TONIGHT AS THE FRONT CROSSES SOUTH CENTRAL ALASKA AND WEAKENS. A
SHORT-WAVE TROUGH WILL CROSS THE AREA FRIDAY AND FRIDAY NIGHT
KEEPING SOME SHOWERS IN THE AREA...MAINLY OVER THE COPPER RIVER
BASIN WHICH WILL BE IN THE SOUTHERLY FLOW AHEAD OF THE TROUGH
LONGER. AN EXTENSION OF THE BRITISH COLUMBIA RIDGE WILL PUSH INTO
SOUTHERN ALASKA SATURDAY FOR A BRIEF BREAK IN THE WEATHER. THE NEXT
SYSTEM WILL PUSH INTO SOUTH CENTRAL ALASKA SUNDAY AS THE RIDGE MOVES
EAST AND SOUTHERLY FLOW ALOFT RETURNS. DETAILS WITH THIS SYSTEM ARE
STILL A LITTLE DIFFICULT TO HASH OUT DUE TO THE MODEL DIFFERENCES
MENTIONED ABOVE.

FOR SOUTHWEST ALASKA...RAIN AND STRONG WINDS WILL CONTINUE TO
DIMINISH OVER THE SOUTHWEST MAINLAND TONIGHT AS THE LOW IN THE
EASTERN BERING BEGINS TO TRACK NORTHWARD. SHOWERY WEATHER AND GUSTY
WINDS WILL PERSIST INTO THE DAY ON FRIDAY WITH THE LOW GRADUALLY
WEAKENING AND MOVING INTO THE NORTHERN BERING...WITH THE STRONGEST
WINDS GENERALLY ALONG THE COAST. UPPER LEVEL RIDGING WILL LEAD TO
TEMPORARILY IMPROVING CONDITIONS LATE FRIDAY EVENING INTO SATURDAY
AFTERNOON...AS A LEADING FRONT ASSOCIATED WITH AN APPROACHING NORTH
PACIFIC LOW WILL BEGIN TO MAKE ITS WAY INTO THE ALASKA PENINSULA
SATURDAY AFTERNOON.

ALEUTIANS/BERING SEA...STORM FORCE WINDS AND HEAVY RAIN WILL REMAIN
OVER MUCH OF THE EASTERN BERING TONIGHT AS THE POWERFUL LOW
CONTINUES TO MOVE NORTHWARD JUST EAST OF THE PRIBILOF ISLANDS. ON
THE BACK END OF THE LOW NORTHERLY GALE FORCE WINDS AND NUMEROUS
SHOWERS CAN BE EXPECTED OVER THE WESTERN ALEUTIANS INTO LATE FRIDAY
MORNING...THEN CONTINUE INTO SUNDAY AFTERNOON AS A WEAKER NORTH
PACIFIC LOW APPROACHES THE CENTRAL ALEUTIANS FROM THE SOUTH. A
WEATHER FRONT ASSOCIATED WITH THE NORTH PACIFIC LOW WILL MAKE ITS
WAY INTO THE CENTRAL AND EASTERN ALEUTIANS FRIDAY NIGHT...BRINGING
RAIN AND GUSTY WINDS TO THE AREA INTO SATURDAY AFTERNOON.

.AER/ALU...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...STORM WARNING 165 170 180 185.
         GALE WARNING 119 120  125 150 155 160 171 172 173 174
                     175 177 178 179 181.
FIRE WEATHER...NONE.

LUDWIG/PEPE OCT 13