Gale Warning 393, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
614 AM AKST WED NOV 18 2015

.SHORT TERM...A GENERAL TROUGH ALOFT EXTENDS ROUGHLY FROM
MIDDLETON ISLAND TO JUST NORTH OF CROSS SOUTH TO NORTH OF POINT
RETREAT. MODERATE TO STRONG SHOWER ACTIVITY ON THE SOUTH SIDE OF
THIS TROUGH IS STREAMING INTO THE PANHANDLE. THE MAIN AXIS OF THE
SHOWERS IS ROUGHLY FROM THE TROUGH TO CAPE DECISION. THE
ATMOSPHERE IS COOL ENOUGH THAT SHOWER ACTIVITY IS SNOW EXCEPT FOR
THE FAR SOUTH WHERE THERE IS SOME RAIN MIXING IN THE MORNING. WILL
LIKELY SEE THIS MIX SPREAD NORTH TO SUMNER STRAIT.

ADVISORIES AND WARNING STILL IN EFFECT FOR CHICHAGOF ISLAND ...
NORTHERN ADMIRALTY...AND THE JUNEAU ZONE. REPORTS SPARSE SO FAR HOWEVER
JUNEAU HAS PICKED UP 6 TO 8 INCHES THUS FAR WITH ANOTHER 3 TO 5
EXPECTED THROUGH THE AFTERNOON. HAVE SOME MINOR CONCERN ORIGINAL
SNOW AMOUNTS WERE LOW FOR PRINCE OF WALES ISLAND...BARANOF AND
KUIU ISLANDS AS THERE WAS A REPORT OF 3.5 INCHES NEAR PETERSBURG.
SHOULD SEE ROUGHLY 1 TO 4 INCHES DEPENDING ON LOCATION AGAIN
TODAY. THE SHOWERS SHOULD CONTINUE THROUGH THE AFTERNOON AND THEN
START DIMINISHING OVERNIGHT. A NEW SURFACE LOW IS EXPECTED TO
REDEVELOP IN THE WESTERN GULF NEAR KODIAK ISLAND WEDNESDAY NIGHT
THEN START TRACKING EAST ACROSS THE NORTHERN GULF. FURTHER WEST A
A STRONG 970 MB LOW WILL BE MOVING NORTHEAST ACROSS THE WESTERN
BERING SEA WITH A WELL DEVELOPED FRONTAL FEATURE.

SMALL CRAFT LEVEL WINDS WITH A LOCAL BARRIER TIP JET NEAR CAPE
DECISION RESULTING A LOCAL WESTERLY GALE FORCE WIND. SEAS ON THE
OUTER WATERS IN THE MID TEENS FOR HEIGHT AND THEY ARE EXPECTED TO
SUBSIDE THROUGH TONIGHT. FORECAST CONFIDENCE IS AVERAGE THROUGH
TONIGHT.

.LONG TERM...AN UPPER LEVEL RIDGE BUILDS SOME OVER THE GULF ON
THURSDAY MORNING KEEPING FLOW OVER THE PANHANDLE NWLY AND COLD
ENOUGH FOR SNOW. THE RIDGE WILL CAUSE SOME BREAKS IN THE PRECIP
EARLY THURSDAY MORNING...ESPECIALLY OVER THE SOUTH. BUT A LOW
(MENTIONED ABOVE) MOVES ACROSS THE NORTHERN GULF AND OVER THE
CENTRAL PANHANDLE THROUGH THE DAY THURSDAY (THIS FOLLOWS A SIMILAR
PATH TO THE ONE FOR THIS MORNING BUT NOT A STRONG). GREATEST
SNOWFALL AMOUNTS WITH THIS LOW LOOK TO BE ALONG THE ICY STRAIT
CORRIDOR THROUGH TO JUNEAU. SOME PLACES WILL BE CLOSE TO ADVISORY
LEVEL AMOUNTS WITH 2 TO 5 INCHES OF SNOW EXPECTED.

ON THE NORTH SIDE OF THIS LOW NORTH WINDS WILL CONTINUE THROUGH
LYNN CANAL. OVERNIGHT THURSDAY THE UPPER LEVEL RIDGE PASSES AND
FLOW BECOMES MORE W-SWLY AND ONSHORE. AS A RESULT WILL SEE
TEMPERATURES RISING THROUGH THURSDAY NIGHT WITH SNOW CHANGING TO
RAIN. BY FRIDAY MORNING SURFACE WINDS WILL HAVE SHIFTED SW WITH
SOUTHERLIES INCREASING THROUGH THE NORTHERN INNER CHANNELS. A
FRONT WILL MOVE INTO THE AREA FROM THE WEST WITH RAIN STARTING IN
YAKUTAT BY FRIDAY MORNING AND OVER THE REST OF THE PANHANDLE
FRIDAY AFTERNOON. PRECIP WITH THIS FRONT SHOULD FALL AS RAIN AS IT
HAS A LONG FETCH OF MOISTURE FROM THE CENTRAL PACIFIC AND 850MB
TEMPERATURES WARMING ABOVE 0C FRIDAY NIGHT. HOWEVER...ONCE THE MAIN
PART OF THE FRONT PASSES ON SATURDAY TEMPERATURES WILL FALL AND
WE'LL SEE A TRANSITION BACK TO SNOW.

AN UPPER LEVEL RIDGE LOOKS TO BUILD AND EXTEND NORTHWARD FROM THE
GULF ACROSS THE STATE WITH N-NWLY FLOW OVER THE PANHANDLE COMING
FROM THE ARCTIC. THE RIDGE REMAINS OVER THE GULF THROUGH MID
WEEK. AT THE SURFACE AN INVERTED TROUGH SETS UP OVER THE
PANHANDLE/EASTERN GULF MONDAY WITH HIGH PRESSURE OVER THE YUKON
AND NORTHERN B.C. THIS CAUSES A TRANSITION BACK TO NORTHERLIES AND
A COLD AND CLEAR PATTERN FOR NEXT WEEK. HAVE DECREASED
TEMPERATURES DURING THIS TIMEFRAME BY SEVERAL DEGREES.

OVERALL MODELS SEEM TO BE IN GOOD AGREEMENT THROUGH THE EXTENDED
FORECAST. FOR THIS REASON HAVE NOT MADE MANY CHANGES TO THE
INHERITED FORECAST FOR PRESSURE/WIND.

&&

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WINTER STORM WARNING UNTIL 4 PM AKST THIS AFTERNOON FOR AKZ025.
         WINTER WEATHER ADVISORY UNTIL 4 PM AKST THIS AFTERNOON FOR
     AKZ021-022.
MARINE...SMALL CRAFT ADVISORY FOR PKZ012-022-041>043-051-052.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ053.

&&

BEZENEK/FERRIN

VISIT US AT HTTP://WWW.WEATHER.GOV/JUNEAU

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE JUNEAU AK
1102 AM AKST WED NOV 18 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0300 PM     HEAVY SNOW       YAKUTAT                 59.54N 139.73W
11/17/2015  M10.6 INCH                          AK   OFFICIAL NWS OBS

0800 AM     HEAVY SNOW       ELFIN COVE              58.19N 136.34W
11/18/2015  E9.0 INCH                           AK   CO-OP OBSERVER

            ESTIMATED AT 8 AM WEDNESDAY BASED ON OBSERVED SNOW DEPTH.

0900 AM     HEAVY SNOW       10 NW JUNEAU            58.40N 134.61W
11/18/2015  M10.0 INCH                          AK   NWS EMPLOYEE

            MEASURED AT FORECAST OFFICE IN MENDENHALL VALLEY.

1030 AM     HEAVY SNOW       8 NW JUNEAU             58.38N 134.57W
11/18/2015  M10.9 INCH                          AK   OFFICIAL NWS OBS

            JUNEAU AIRPORT MEASURED 7.6 INCHES SINCE MIDNIGHT. IN
            ADDITION TO 3.3 INCHES THAT FELL YESTERDAY, STORM TOTAL
            NOW STANDS AT 10.9 INCHES.

&&

RCL