Small Craft Advisory 47, NWS Juneau, AK

SOUTHEAST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JUNEAU AK
400 PM AKST SAT JAN 15 2011

.SHORT TERM... SATELLITE IMAGERY SHOWS THE AREA OF CLOUDS AND
SNOW HAS ADVANCED AS FAR NORTH AS JUNEAU HOWEVER THE HIGHER
CLOUDS ARE MORE BANDED THAN SOLID AND AS A RESULT THE SNOWFALL IS
QUITE VARIABLE. SURFACE OBSERVATIONS SHOW LIGHT SNOW IS FALLING
OVER MOST OF THE SOUTHERN TWO THIRDS OF THE PANHANDLE BUT
TEMPERATURES HAVE WARMED ABOVE FREEZING IN THE EXTREME SOUTH AND
A SLOW WARMING IS EXPECTED TO CONTINUE THROUGH SUNDAY. BECAUSE OF
THE STRONGER THAN EXPECTED WARM UP A WINTER STORM WARNING FOR
HEAVY SNOW IS CURRENTLY ONLY IN EFFECT FOR ZONE 29 AND A WINTER
WEATHER ADVISORY FOR SNOW IS CONTINUED FOR ZONE 26. LITTLE CHANGE
IS EXPECTED TO THE THE GENERAL WARM MOIST OVERRUNING CONDITION
THROUGH SUNDAY OTHER THAN A VERY GRADUAL MODIFICATION OF THE
ARCTIC OUTFLOW AIRMASS BELOW.

 MODELS ARE FAIRLY CONSISTENT WITH THE SYNOPTIC PATTERN. STRONG
HIGH PRESSURE WILL CONTINUE IN THE YUKON THROUGH EARLY SUNDAY
WHICH WILL MAINTAIN THE INTENSE NORTH TO NORTHEAST WINDS IN THE
NORTHERN AND INTERIOR ZONES WHILE KEEPING TEMPERATURES COLD. A
WINTER STORM WARNING FOR DANGEROUS WIND CHILLS WAS ISSUED FOR
ZONE 18 WHICH INCLUDES SKAGWAY AND THE KONDIKE HIGHWAY. THESE
CONDITIONS ARE EXPECTED TO CONTINUE THROUGH EARLY SUNDAY.
&&

.LONG TERM...WE WILL BE IN A SLOW WARM UP THROUGH THE LONG TERM.
ONE LAST BURST OF ARCTIC AIR SUNDAY NIGHT BEFORE RIDGE BUILDS INTO
GULF AND GO TO ONSHORE FLOW. DO HAVE A SHORT WAVE IN WESTERLY FLOW
THAT MOVES ACROSS PANHANDLE MONDAY AND A WEAK SYSTEM THAT APPROACHES
FROM SW ON TUESDAY. THESE SYSTEMS WILL BRING SNOW TO THE INNER
CHANNELS WITH A MIX OF RAIN AND SNOW ALONG THE IMMEDIATE COAST.

A STRONGER FRONTAL SYSTEMS MOVES INTO THE EASTERN GULF WEDNESDAY
WITH GALES. PRECIP WILL INCREASE ACROSS PANHANDLE AND COULD SEE
ADVISORY LEVEL SNOWS FOR INNER CHANNELS WED-THU. HAVE PRECIP GOING
TO ALL RAIN EXCEPT FOR PAHN-PAGY THU NIGHT AND FRI.

MODELS IN GOOD SYNOPTIC AGREEMENT. USED NAM FOR PRES-WIND THROUGH
DAY 3.5 BUT IT IS WAY TOO COLD (HAD A -12C COLD BIAS AT PAKT THIS
MORNING) IN THE BOUNDARY LEVEL. PRIMARILY USED GFS FOR TEMPS AND
OTHER FIELDS THROUGH DAY 4 AND HPC GRIDS DAYS 4-8.

.AJK WATCHES/WARNINGS/ADVISORIES...
PUBLIC...WINTER WEATHER ADVISORY UNTIL 3 AM AKST SUNDAY FOR AKZ026.
         WIND ADVISORY UNTIL NOON AKST SUNDAY FOR AKZ017-019-020-022-025.
         WINTER STORM WARNING UNTIL 3 PM AKST SUNDAY FOR AKZ018-029.
MARINE...HEAVY FREEZING SPRAY WARNING FOR PKZ011>013-021-022-031-032-043.
         STORM WARNING FOR PKZ011>013.
         GALE WARNING FOR PKZ021-022-031-032-034-035-042.
         SMALL CRAFT ADVISORY FOR PKZ033-036-041-043-051.
         SMALL CRAFT ADVISORY DUE TO SEAS FOR PKZ052.

&&

CFD/MM

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE JUNEAU AK
217 PM AKST SAT JAN 15 2011

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

0730 AM     EXTR WIND CHILL  WHITE PASS              59.62N 135.14W
01/15/2011  E-51 F                              AK   LAW ENFORCEMENT

            THE SUMMIT/BORDER RECORDING FROM THE KLONDIKE HIGHWAY
            REPORTED A SUMMIT TEMPERATURE OF -22 DEGREES FARENHEIT
            WITH A NORTH WIND 20 TO 30 MPH. THIS PRODUCES A WIND
            CHILL TO AT LEAST -51 DEGREES FARENHEIT.

0524 PM     NON-TSTM WND GST DOUGLAS                 58.27N 134.39W
01/14/2011  M79 MPH                             AK   MESONET

            THE SOUTH DOUGLAS WIND SENSOR REPORTED A PEAK WIND OF 79
            MPH.

0836 PM     NON-TSTM WND GST DOUGLAS                 58.27N 134.39W
01/14/2011  M71 MPH                             AK   MESONET

            THE MAY FLOWER ISLAND WIND SENSOR RECORDED FREQUENT GUSTS
            TO 64 MPH WITH A PEAK WIND OF 71 MPH.

0800 AM     SNOW             9 N PETERSBURG          56.94N 132.96W
01/15/2011  M2.0 INCH        PKZ034             AK   CO-OP OBSERVER

            PETERSBURG WEATHER OBSERVER REPORTED 2 INCHES OF NEW SNOW
            FROM START OF SNOW UNTIL 8 AM. WAS STILL LIGHTLY SNOWING
            AT TIME OF CALL.

0815 AM     SNOW             THORNE BAY              55.67N 132.50W
01/15/2011  M1.8 INCH                           AK   CO-OP OBSERVER

            1.8 INCHES OF SNOW FOR A 24 HOUR TOTAL.

0815 AM     SNOW             THORNE BAY              55.67N 132.50W
01/15/2011  E0.0 INCH                           AK   CO-OP OBSERVER

            VISIBILITY OF LESS THEN A QUARTER MILE DUE TO DRIFTING
            AND BLOWING SNOW.

0830 AM     NON-TSTM WND DMG HAINES                  59.24N 135.44W
01/15/2011                                      AK   CO-OP OBSERVER

            HAINES CO-OP REPORTED WIND DAMAGE NEAR THE FERRY TERMINAL
            6 MILES NORTH OF HAINES. A TREE HAD BEEN BLOWN ACROSS THE
            ROAD.

0900 AM     SNOW             KETCHIKAN               55.34N 131.65W
01/15/2011  E2.0 INCH                           AK   LAW ENFORCEMENT

            KETCHIKAN FIRE DEPARTMENT REPORTED 2 INCHES OF SNOW ON
            THE GROUND SINCE SNOW BEGAN. RAIN WAS BEGINNING TO MIX
            WITH SNOW.

0930 AM     SNOW             EDNA BAY                55.95N 133.66W
01/15/2011  E2.0 INCH                           AK   TRAINED SPOTTER

            2 INCHES OF SNOW HAD FALLEN SINCE THE SNOW BEGAN. STILL
            SNOWING LIGHTLY AND RAIN HAD NOT BEGUN TO MIX WITH SNOW.

0930 AM     SNOW             KETCHIKAN               55.34N 131.65W
01/15/2011  E3.0 INCH                           AK   TRAINED SPOTTER

            3 INCHES OF SNOW HAD FALLEN SINCE SNOW BEGAN. WAS
            CURRENTLY 30 DEGREES FARENHEIT WITH NO PRECIP FALLING AT
            TIME OF OBSERVATION.

0945 AM     SNOW             ANNETTE                 55.04N 131.59W
01/15/2011  M2.0 INCH                           AK   NWS EMPLOYEE

            2 INCHES OF SNOW HAD FALLEN SINCE SNOW BEGAN. WAS
            CURRENTLY 33 DEGREES FARENHEIT WITH LIGHT SNOW FALLING.

0945 AM     SNOW             HYDER                   55.91N 130.02W
01/15/2011  E4.0 INCH                           AK   TRAINED SPOTTER

            3 TO 4 INCHES OF SNOW HAD FALLEN SINCE SNOW BEGAN. WAS
            SNOWING STEADILY BUT LIGHTLY AT TIME OF OBSERVATION.

1000 AM     NON-TSTM WND GST 3 WNW AUKE BAY          58.40N 134.73W
01/15/2011  E0 MPH                              AK   TRAINED SPOTTER

            LOOKING ACROSS THE WATER COULD NOT SEE ADMIRALTY ISLAND.
            VISIBILITY WAS REDUCED TO LESS THEN 2 MILES DUE TO SEA
            SPRAY FROM LYNN CANAL.

1120 AM     ICE STORM        KLAWOCK                 55.55N 133.09W
01/15/2011                                      AK   TRAINED SPOTTER

            A QUARTER INCH OF ICE ACCUMULATION WAS REPORTED BY A
            KLAWOCK TRAINED SPOTTER. ICE WAS ACCUMULATING ON TREES
            AND OBJECTS.

1120 AM     SNOW             WRANGELL                56.47N 132.40W
01/15/2011  M3.5 INCH                           AK   OFFICIAL NWS OBS

            3.5 INCHES OF SNOW HAD FALLEN SINCE SNOW BEGAN THE NIGHT
            BEFORE TO THE CURRENT TIME.

1200 PM     SNOW             9 N PETERSBURG          56.94N 132.96W
01/15/2011  M1.5 INCH        PKZ034             AK   CO-OP OBSERVER

            1.5 INCHES OF NEW SNOW HAD FALLEN SINCE THIS MORNINGS
            OBSERVATION OF 2 INCHES OF NEW SNOW.

0922 AM     ICE STORM        KLAWOCK                 55.55N 133.09W
01/15/2011                                      AK   ASOS

            FREEZING RAIN WAS REPORTED BEGINNING AT THE KLAWOCK ASOS
            AT 1822Z AND ENDED AT 1918Z.

&&

CJL