Storm Warning 106, NWS Anchorage, AK

733 
FZAK61 PAFC 120009
OFFAER

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
309 PM AKST WED NOV 11 2015

OFFSHORE WATERS FORECAST FOR THE GULF OF ALASKA WEST OF 144W

WIND FORECASTS REFLECT THE PREDOMINANT SPEED AND DIRECTION
EXPECTED. SEA FORECASTS REPRESENT AN AVERAGE OF THE HIGHEST
ONE-THIRD OF THE COMBINED WIND WAVE AND SWELL HEIGHT.

PKZ399-121430-
309 PM AKST WED NOV 11 2015
.SYNOPSIS FOR THE WESTERN GULF OF ALASKA...
A 964 MB LOW AT 56N 156W MOVES TO 58N 143W AT 992 MB THU MORNING...THEN
SLOWLY WEAKENS TO 979 MB AND MOVES TO 58N 141W FRI AFTERNOON.


$$

PKZ351-121430-
GULF OF ALASKA OFFSHORE NORTH OF 57N AND WEST OF 144W-
309 PM AKST WED NOV 11 2015

...GALE WARNING THROUGH THURSDAY NIGHT...

.TONIGHT...S WIND 30 TO 45 KT BECOMING SE 10 TO 25 KT AFTER
MIDNIGHT. SEAS 14 TO 22 FT. RAIN.
.THU...NW WIND 20 TO 35 KT. SEAS 16 TO 25 FT. RAIN SHOWERS.
.THU NIGHT...NW WIND 20 TO 35 KT. SEAS 13 TO 21 FT. RAIN SHOWERS.
.FRI...NW WIND 20 TO 35 KT. SEAS 11 TO 17 FT.
.FRI NIGHT...NW WIND 20 TO 35 KT. SEAS 9 TO 15 FT.
.SAT...W WIND 15 TO 30 KT. SEAS 8 TO 13 FT.
.SUN THROUGH MON...NW WIND 15 TO 30 KT. SEAS 5 TO 10 FT.

$$

PKZ352-121430-
GULF OF ALASKA OFFSHORE SOUTH OF 57N NORTH OF 55N AND WEST OF
144W-
309 PM AKST WED NOV 11 2015

...STORM WARNING TONIGHT...

.TONIGHT...W WIND 35 TO 50 KT. SEAS 18 TO 28 FT BUILDING 30 TO 40
FT AFTER MIDNIGHT. RAIN SHOWERS.
.THU...W WIND 30 TO 45 KT. SEAS 27 TO 39 FT. RAIN SHOWERS.
.THU NIGHT...W WIND 30 TO 40 KT. SEAS 18 TO 27 FT.
.FRI...NW WIND 30 TO 40 KT. SEAS 17 TO 20 FT.
.FRI NIGHT...NW WIND 35 KT. SEAS 15 TO 18 FT.
.SAT...W WIND 15 TO 30 KT. SEAS 10 TO 18 FT.
.SUN THROUGH MON...NW WIND 15 TO 30 KT. SEAS 6 TO 11 FT.

$$

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
449 PM AKST TUE NOV 10 2015

.ANALYSIS AND UPPER LEVELS...THE JET IS READILY APPARENT WITH ONE
LOOK AT THE IR SATELLITE. IT IS STREAMING ALONG THE ALEUTIAN CHAIN
BETWEEN 140-150 KTS. IT IS PROVIDING SOME UPPER LEVEL SUPPORT TO
THE RAPIDLY DEEPENING CYCLONE OVER THE WESTERN ALEUTIANS. IT WILL
CONTINUE TO DO SO AS THE LOW INTERACTS WITH THE LEFT EXIT JET REGION
THROUGH THE DAY INTO TONIGHT. THE JET THEN TRACKS OFF TO THE EAST
AND DIVES SOUTHEAST IN THE GULF BEFORE TURNING SHARPLY BACK TO THE
NORTH AGAIN ALONG THE PANHANDLE. THIS IS KEEPING THE BROAD
LONGWAVE TROUGH OVER THE MAINLAND WITH COLD AIR ALOFT. THIS COLD
AIR IS CONTINUING TO TRIGGER SHOWERS ACROSS MUCH OF THE SOUTHERN
HALF OF THE STATE...ESPECIALLY OVER THE GULF WHERE THE WARM SEA
SURFACE TEMPERATURES HAVE HELPED PRODUCE SOME LIGHTNING THIS
MORNING. THESE SHOWERS HAVE QUICKLY DROPPED VISIBILITY AT TIMES
AND PUT DOWN SOME LIGHT ACCUMULATIONS AT SOME OF THE POPULATION
CENTERS. A FEW WEAK WAVES OF ENERGY CONTINUE TO ROTATE AROUND THE
DECAYING LOW NEAR THE SEWARD PENINSULA ARE SWINGING THROUGH THE
SOUTHERN PORTION OF THE STATE IN THE BROAD CYCLONIC FLOW AS WELL.
THESE ARE SERVING TO CONSOLIDATE THE SHOWERS AT TIMES...BUT JUST
ABOUT ALL AREAS WILL BE VULNERABLE TO A BRIEF SHOT OF SNOW OR A
RAIN/SNOW MIX CLOSER TO THE COAST.

A FEW SURFACE OBSERVATIONS AND ASCAT(SATELLITE DERIVED WINDS) PASSES
OVER THE WESTERN ALEUTIANS CONFIRM THAT THE DEEPENING STORM IS ON
TRACK. SOUTHWEST GUSTS TO 60 MPH HAVE BEEN REPORTED AT ADAK AND
THINGS WILL ONLY CONTINUE TO INTENSIFY AS SOME STRATOSPHERIC AIR
GETS PULLED DOWN INTO THE LOWER LEVELS.

&&

.MODEL DISCUSSION...MODELS ARE SHOWING GOOD AGREEMENT ON THE
SYNOPTIC SCALE. THIS IS MAKING FOR MODERATE TO HIGH CONFIDENCE IN
MANY OF THE BIG PICTURE ITEMS. THIS INCLUDES WARNING LEVEL WINDS
ACROSS MUCH OF THE ALEUTIANS AND PARTS OF THE ALASKA PENINSULA. IT
ALSO INCLUDES THE TRACK OF THE LOW INTO THE GULF IN THAT IT LOOKS
LIKE MOST OF THE PRECIPITATION WILL STAY CONFINED TO THE COASTAL
REGIONS. SOME OF THE LESS CERTAIN ITEMS WHERE MODELS DISAGREE ARE
HOW COLD THE AIRMASS STAYS OVER ST PAUL ISLAND AND EXACTLY WHAT
PRECIPITATION TYPE WILL FALL OVER THE GULF COAST LOCATIONS. FOR ST
PAUL...MODELS CONTINUE TO STRUGGLE TO NAIL DOWN THE EXACT
PRECIPITATION TYPE. BUT AS OF THE 18Z RUNS...THEY HAVE TRENDED
SLIGHTLY FARTHER SOUTH WITH THE SYSTEM. THIS SHOULD ALLOW MOST OF
THE PRECIPITATION THERE TO FALL AS SNOW...ALBEIT A WET HEAVY SNOW.
FOR THE GULF OF ALASKA COAST...THERE IS ALSO SOME UNCERTAINTY.
WE LEANED ON THE FASTER...FARTHER SOUTH SOLUTIONS (EC-GEM
REGIONAL) WITH SUCH A STRONG ZONAL JET. THIS WOULD KEEP PLACES
LIKE THE EASTERN TURNAGAIN ARM AND POSSIBLY EVEN SEWARD ALL SNOW
AS COLD AIR IS PULLED NORTH TO SOUTH OFF THE LAND INTO THE SYSTEM.
BUT A SLIGHT JOG TO THE NORTH COULD DRAMATICALLY CHANGE
TEMPERATURES AND PRECIPITATION TYPES.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 AND 2)...

AN UPPER LEVEL TROUGH IS CENTERED OVER THE REGION THIS AFTERNOON...AND
WILL MOVE EAST INTO CANADA TONIGHT. ISOLATED TO SCATTERED SNOW SHOWERS
WILL LARGELY BE RELEGATED TO THE MOUNTAINS...BUT CONTINUED FAVORABLE
FLOW INTO THE NORTHERN SUSITNA VALLEY WILL SUPPORT LIGHT SNOW
ACCUMULATIONS INTO WEDNESDAY MORNING. WITH PARTIALLY CLEARING
SKIES AND LIGHT WINDS...PATCHY FOG THREATS WILL DEVELOP FROM COOK
INLET NORTH...ESPECIALLY ACROSS FAVORED VALLEYS AND BASINS.

ATTENTION QUICKLY TURNS TO A FAST MOVING STORM FORCE LOW WHICH
WILL MOVE INTO THE GULF OF ALASKA WEDNESDAY AND WEDNESDAY NIGHT.
THE TRACK IS TAKING A SLIGHTLY FARTHER SOUTH TRAJECTORY...WHICH
WILL KEEP PRECIPITATION GENERALLY ALONG THE COAST. VERY STRONG
EASTERLY LOW LEVEL FLOW WILL RESULT IN A VERY WELL DEFINED
DOWNSLOPE SHADOW FOR INTERIOR LOCATIONS...WITH RAIN AND SNOW FOR
COASTAL LOCATIONS...EXCEPT ALL RAIN FOR KODIAK ISLAND. THE
PRESSURE GRADIENT WILL BECOME OFFSHORE...WITH GAP WINDS INCREASING
WEDNESDAY AFTERNOON AND CONTINUING THROUGH THURSDAY.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (DAYS 1 AND 2)...

SNOW SHOWERS WILL PERSIST THIS EVENING ACROSS THE AREA. WEAK
RIDGING WILL END PRECIPITATION FOR THE KUSKOKWIM VALLEY AND DELTA
WED THROUGH THU. THE ALEUTIAN LOW WILL SPREAD RAIN AND SNOW
SHOWERS OVER THE BRISTOL BAY ZONE THROUGH THU AS IT MOVES EAST TO
THE AKPEN AND BEYOND.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (DAYS 1 AND 2)...

AS THE ALEUTIAN LOW MOVES EAST IT WILL SPREAD DANGEROUS WINDS
ACROSS THE CENTRAL ALEUTIANS THROUGH TONIGHT...THE EASTERN
ALEUTIANS THIS EVENING THROUGH WEDNESDAY AFTERNOON...AND THE
ALASKA PENINSULA WEDNESDAY AND WEDNESDAY EVENING. HIGH WIND
WARNINGS REMAIN IN EFFECT FOR THESE AREAS. AS THE LOW MOVES PAST
THE PRIBILOF ISLANDS TONIGHT...THE LINE SEPARATING COLD FROM WARM
AIR MASSES WILL LIE BETWEEN SAINT PAUL AND SAINT GEORGE. WIND AND
SNOW OVER SAINT PAUL WILL CREATE AREAS OF LOW VISIBILITY...AND A
WINTER WEATHER ADVISORY FOR BLOWING SNOW IS IN EFFECT FOR TONIGHT
INTO WEDNESDAY MORNING. WHILE THIS IS HAPPENING...RAIN AND WIND
WILL AFFECT SAINT GEORGE.

OTHERWISE DIMINISHING WIND OVER THE WESTERN ALEUTIANS WILL SPREAD
ACROSS THE CHAIN THROUGH THU...WHILE PERSISTENT NORTHWEST FLOW
WILL KEEP SNOW SHOWERS OVER THE BERING AND ALEUTIANS THROUGH THE
SAME PERIOD.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
THE MODELS ARE IN GOOD AGREEMENT WITH THE PLACEMENT OF THE STRONG LOW
THAT TRACKS FROM THE BERING SEA INTO THE CENTRAL GULF. BY
THURSDAY AFTERNOON THIS SYSTEM WILL BE POSITIONED JUST OFF THE
COAST NEAR YAKUTAT. THE EASTERN KENAI PENINSULA...PRINCE WILLIAM
SOUND AND THE NORTHERN COASTAL REGION WILL GET THE BULK OF THE
PRECIPITATION. THERE WILL BE RAIN AND SNOW ALONG THE COASTLINE
BEFORE TRANSITIONING TO ALL SNOW INLAND ALONG THE CHUGACH AND
KENAI MOUNTAINS. THE INTERIOR WILL RECEIVE WRAP-AROUND MOISTURE
FROM THE LOW PRESSURE SYSTEM AND THE ANCHORAGE BOWL WILL FOR THE
MOST PART BE DOWN-SLOPED OUT RESULTING IN DRIER CONDITIONS.
UPSTREAM COLD AIR WILL FILTER INTO THE SOUTHCENTRAL REGION BY
THURSDAY WITH THE OVERALL WIND FLOW SHIFTING FROM ONSHORE TO
OFFSHORE FLOW THROUGH THE WEEKEND. THE COLD AIR ADVECTION WILL
INCREASE THE PRESSURE GRADIENTS RESULTING IN STRONG GUSTY
NORTHWESTERLY GAP WINDS THROUGH THE WESTERN GULF FROM SHELIKOF
STRAIT...BARREN ISLANDS...COOK INLET AND THROUGH THE WHITTIER AND
PORTAGE REGION. HEADING INTO THE WEEKEND THE WINDS WILL BECOME
MORE NORTHERLY AND THE SOUTHCENTRAL REGION WILL SEE COOLER
TEMPERATURES IN THE SINGLE DIGIT RANGE COINCIDING AS MORE COLDER
AIR FILTERING INTO THE REGION.

THE BERING SEA AND THE ALEUTIAN CHAIN WILL BE UNDER THE INFLUENCE
OF NORTHWESTERLY FLOW RESULTING IN A SHOWERY WEATHER REGIME
THROUGH THE WEEKEND. THE COLD AIR WILL CONTINUE TO DROP DOWN FROM
THE NORTH BRINGING COOLER TEMPERATURES WITH PRECIPITATION FALLING
AS SNOW SHOWERS. THE HEAVIEST SNOW SHOWERS WILL OCCUR ALONG THE
EASTERN ALEUTIANS THROUGH THE NEXT SEVERAL DAYS. BY SUNDAY EVENING
A HIGH PRESSURE RIDGE WILL BEGIN TO BUILD INTO THE WESTERN
ALEUTIANS AND THE LOWER WESTERN BERING SEA.

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...HIGH WIND WARNINGS 181 185 187. BLOWING SNOW ADVISORY 195.
MARINE...HURRICANES 155 170 171 172 173
         STORMS 119 120 130 139 150 165 174 175 176 179
         GALES 125 127 131 132 136 137 138 140 141 160 177 180.

&&

SYNOPSIS AND MODEL DISCUSSION...MO
SOUTHCENTRAL ALASKA...JA
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...DS
LONG TERM...PD

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ANCHORAGE AK
1220 AM AKST WED NOV 11 2015

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

0500 PM     NON-TSTM WND GST ADAK STATION            51.84N 176.64W
11/10/2015  M70.00 MPH                          AK   AWOS

0720 PM     NON-TSTM WND GST ATKA                    52.24N 174.21W
11/10/2015  M67.00 MPH                          AK   AWOS

&&

JPW