Storm Warning 145, NWS Anchorage, AK

438 
FZAK62 PAFC 150019
OFFALU

OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE ANCHORAGE AK
319 PM AKST SUN DEC 14 2014

OFFSHORE WATERS FORECAST FOR THE BERING SEA

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.

PKZ499-151415-
319 PM AKST SUN DEC 14 2014
.SYNOPSIS FOR CENTRAL BERING SEA...
A 965 MB LOW NEAR 56N 166W WILL MOVE TO 58N 174WW AT 974 MB TUE
AFTERNOON. A 980 MB LOW NEAR 58N 177W DISSIPATES LATE MON
AFTERNOON. A 987 MB LOW NEAR 50N 171E TONIGHT MOVES TO 51N 177W
TUE AFTERNOON WITH LITTLE CHANGE IN INTENSITY.

$$

PKZ411-151415-
BERING SEA OFFSHORE WEST OF 180 AND EAST OF THE INTERNATIONAL
DATELINE-
319 PM AKST SUN DEC 14 2014

.TONIGHT...W WIND 15 TO 25 KT...EXCEPT NE 30 KT N OF 56N. SEAS 12
TO 15 FT. RAIN AND SNOW. 
.MON...W WIND 10 TO 25 KT...EXCEPT NE 30 KT N OF 56N. SEAS 11 TO
16 FT. RAIN AND SNOW.
.MON NIGHT...N WIND 15 TO 30 KT. SEAS 10 TO 17 FT. RAIN AND SNOW.
.TUE...N WIND 15 TO 30 KT. SEAS 11 TO 18 FT.
.TUE NIGHT...N WIND 30 KT. SEAS 14 TO 18 FT.
.WED...N WIND 10 TO 25 KT. SEAS 9 TO 15 FT.
.THU...NE WIND 20 TO 35 KT. SEAS 10 TO 17 FT.
.FRI...N WIND 30 KT. SEAS 13 TO 18 FT.

$$

PKZ412-151415-
BERING SEA OFFSHORE 171W TO 180 AND NORTH OF 56N-
319 PM AKST SUN DEC 14 2014

.TONIGHT...NW WIND 15 TO 30 KT...EXCEPT NE 30 KT N OF 56N. SEAS
12 TO 17 FT. SNOW AND RAIN.
.MON...W WIND 15 TO 30 KT...EXCEPT NE 30 KT N OF 56N. SEAS 12 FT.
RAIN AND SNOW.
.MON NIGHT...NW WIND 15 TO 30 KT. SEAS 11 TO 15 FT. RAIN AND SNOW.
.TUE...NW WIND 15 TO 25 KT. SEAS 10 TO 15 FT.
.TUE NIGHT...NW WIND 15 TO 30 KT. SEAS 9 TO 15 FT.
.WED...NW WIND 15 TO 30 KT. SEAS 8 TO 13 FT.
.THU...E WIND 15 TO 30 KT. SEAS 7 TO 12 FT.
.FRI...NE WIND 30 KT. SEAS 9 TO 16 FT.

$$

PKZ413-151415-
BERING SEA OFFSHORE 171W TO 180 AND SOUTH OF 56N-
319 PM AKST SUN DEC 14 2014

...GALE WARNING TONIGHT...

.TONIGHT...W WIND 25 TO 40 KT DIMINISHING TO 20 TO 30 KT AFTER
MIDNIGHT. SEAS 14 TO 20 FT. RAIN AND SNOW.
.MON...W WIND 20 TO 30 KT. SEAS 12 TO 16 FT.
.MON NIGHT...W WIND 10 TO 25 KT. SEAS 9 TO 14 FT.
.TUE...W WIND 10 TO 25 KT. SEAS 9 TO 12 FT.
.TUE NIGHT...NW WIND 10 TO 25 KT. SEAS 9 TO 13 FT.
.WED...W WIND 10 TO 25 KT. SEAS 8 TO 13 FT.
.THU...E WIND 20 TO 35 KT. SEAS 8 TO 13 FT.
.FRI...N WIND 30 KT. SEAS 9 TO 17 FT.

$$

PKZ414-151415-
BERING SEA OFFSHORE EAST OF 171W-
319 PM AKST SUN DEC 14 2014

...GALE WARNING THROUGH MONDAY...

.TONIGHT...NW WIND 30 TO 45 KT EXCEPT NE 25 TO 40 KT N OF 56N.
SEAS 14 TO 20 FT. RAIN AND SNOW.
.MON...W WIND 20 TO 35 KT. SEAS 9 TO 14 FT. RAIN AND SNOW.
.MON NIGHT...W WIND 20 TO 30 KT. SEAS 9 TO 13 FT. RAIN AND SNOW.
.TUE...SW WIND 20 TO 30 KT. SEAS 10 TO 13 FT.
.TUE NIGHT...SW WIND 15 TO 25 KT. SEAS 7 TO 10 FT.
.WED...W WIND 10 TO 20 KT. SEAS 4 TO 8 FT.
.THU...SE WIND 15 TO 30 KT. SEAS 6 TO 11 FT.
.FRI...NE WIND 30 KT. SEAS 8 TO 13 FT.

$$

SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
454 PM AKST SAT DEC 13 2014

.ANALYSIS AND UPPER LEVELS...
TODAY'S WEATHER CHART SHOWS THE SAME UPPER PATTERN CONSISTING OF
LONGWAVE RIDGING ALONG THE WEST COAST OF NORTH AMERICA AND A TROF
IN THE BERING. HOWEVER, THE SOUTHERLY FLOW BETWEEN THESE TWO
FEATURES IS MORE VARIED BOTH IN DIRECTION AND MAGNITUDE AS THE
NORTON SOUND UPPER LOW MOVES TO THE WESTERN NORTH SLOPE SATURDAY
NIGHT. ASSOCIATED TROUGH AXIS OR FRONT TRAILS BACK ALONG THE
WESTERN ALASKA RANGE WITH THE BULK OF THE MOISTURE ALREADY OFF TO
THE NORTH. THE POSITIVE VORTICITY ADVECTION SHOULD PROVIDE ENOUGH
LIFT TO MAINTAIN A NARROW BAND OF PRECIPITATION SOME OF WHICH MAY
SLIP ON OVER TO WESTERN COOK INLET AND, TO A LESSER EXTENT, THE
WEST SIDE OF THE SUSITNA VALLEY TONIGHT AND SUNDAY AS EASTERN
AREAS, AWAY FROM THE COAST STAY MOSTLY DRY.

STRONG FRONT LIFTING NORTH TO BRING EASTERLY GALES TO THE NORTH
GULF COAST TONIGHT AND POSSIBLY PRINCE WILLIAM LATE TONIGHT AND
PART OF SUNDAY. PERIODS OF RAIN ALL ALONG THE COAST TO KODIAK NEXT
FEW DAYS AS SEVERAL SURGES OF MOISTURE MOVE NORTH NORTHWEST IN
PERSIST SOUTHEASTERLY FLOW.

GALES AND POSSIBLE STORMS TONIGHT THROUGH SUNDAY NIGHT WITH RAIN
HEAVY AT TIMES FOLLOWED BY COOLER MORE SHOWERY CONDITIONS WITH
BRISK WET WINDS.

&&

.MODEL DISCUSSION...
WESTERN DOMAIN FORECASTER CHOSE THE EC WHILE THE EASTERN
FORECASTER FAVORED THE NAM.

&&

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (TONIGHT THROUGH MONDAY)...
ABUNDANT PRECIPITATION WILL REMAIN FOCUSED ALONG THE GULF COAST
THROUGH MONDAY AS A LOW PRESSURE SYSTEM MOVES THROUGH THE GULF
WITH AN ASSOCIATED FRONT ARRIVING ALONG THE COAST THIS EVENING.
THE MAIN FORECAST CHALLENGE WILL BE DETERMINING THE POTENTIAL FOR
PRECIPITATION FURTHER INLAND FROM ANCHORAGE INTO THE MAT-SU AS A
FAIRLY COMPLEX PATTERN SETS UP OVER THE REGION. THE LIMITING
FACTOR WILL BE STRONG SOUTHEAST FLOW IN THE MID LEVELS AND THE
ASSOCIATED DOWNSLOPE DRYING...HOWEVER SEVERAL OTHER FEATURES AT
PLAY MAY BE ENOUGH TO OVERCOME THIS ISSUE. SOUTHWESTERLY UPPER
LEVEL FLOW COUPLED WITH JET ENERGY ALOFT MOVING OVER THE AREA
TONIGHT FOLLOWED BY THE UPPER TROUGH OVER THE GULF LIFTING INLAND
ON SUNDAY MAY PROVIDE ENOUGH MOISTURE/DYNAMIC SUPPORT TO GENERATE
SOME LIGHT PRECIPITATION OVER INLAND PORTIONS OF SOUTHCENTRAL
THROUGH MONDAY. ANY PRECIPITATION THAT DOES FALL SHOULD REMAIN
MOSTLY SNOW THROUGH TONIGHT BEFORE CHANGING OVER TO RAIN DURING
THE DAY ON SUNDAY AS WARMER AIR SURGES NORTHWARD BEHIND THE FRONT.

&&

.SHORT TERM FORECAST SOUTHWEST ALASKA (TODAY THROUGH MONDAY)...
ANOTHER PERIOD OF LIGHT SNOW WILL MOVE THROUGH THE KUSKOKWIM DELTA
AND WESTERN BRISTOL BAY TODAY AS A UPPER LEVEL SHORT WAVE PUSHES
THROUGH. THIS SHOULD ONCE AGAIN BRING ONLY LIGHT ACCUMULATIONS WITH
MOST AREAS RECEIVING LESS THAN AN INCH OR SO. THIS SNOW WILL
QUICKLY DIMINISH BY THIS EVENING WITH WEAK RIDGING MOVING
IN...WHICH WILL BE SHORT LIVED AS THE NEXT CHANCE OF
PRECIPITATION IS EXPECTED BY SUNDAY. THIS WILL MAINLY BRING SNOW
TO BRISTOL BAY...WHICH WILL SLOWLY BECOME A RAIN/SNOW MIX BY
SUNDAY EVENING...LIMITING SNOWFALL ACCUMULATIONS. WITH THE COLD
AIR CURRENTLY OVER THE AREA THERE IS A SLIGHT CHANCE THAT SOME
AREAS OF FREEZING RAIN COULD DEVELOP SUNDAY AFTERNOON AND
EVENING...BUT WITH MODERATE WARMING FROM BOTH ADVECTION AND
DOWNSLOPING THIS IS EXPECTED TO BE FAIRLY SHORT LIVED. RAIN AND
SNOW WILL THEN LIKELY CONTINUE INTO MONDAY AS A SHORTWAVE UPPER
LEVEL TROUGH STALLS OVERHEAD.

&&

.SHORT TERM FORECAST BERING SEA/ALEUTIANS (TODAY THROUGH MONDAY)...
A GALE FORCE FRONT STRETCHING FROM THE EASTERN ALEUTIANS INTO THE
PRIBILOFS WILL BRING RAIN AND SNOW AS WELL AS GUSTY SOUTHERLY
WINDS THROUGH THIS AFTERNOON. AS THIS FRONT DISSIPATES OVER THE
NORTHERN BERING THIS EVENING...A DEVELOPING TRIPLE POINT LOW
TRACKING TOWARDS THE CENTRAL ALEUTIANS WILL BRING ANOTHER ROUND OF
RAIN/SNOW AND AT LEAST GALE FORCE WINDS TO THE EASTERN BERING AND
ALEUTIANS INTO SUNDAY. THIS LOW WILL THEN VERY SLOWLY DISSIPATE AS
IT MOVES TOWARDS THE AKPEN BY MONDAY MORNING...ALLOWING FOR
SHOWERS AND GUSTY WINDS TO CONTINUE.

&&

.LONG TERM FORECAST (DAYS 3 THROUGH 7)...
THE JET STREAM MAINTAINS A STRONG WESTERLY FLOW JUST SOUTH OF THE
ALEUTIANS WHICH KEEPS AN ACTIVE WEATHER PATTERN THROUGH THE END OF
NEXT WEEK AS IT PUSHES MULTIPLE LOW PRESSURE SYSTEMS FROM THE
WESTERN BERING TO THE EASTERN GULF. MODEL SOLUTIONS WERE IN DECENT
AGREEMENT WITH LONG RANGE SOLUTIONS...HOWEVER THE ECMWF WAS
PREFERRED AS IT PERFORMED BETTER ON THE LATEST RUN TO RUN
CONSISTENCY.

ON MONDAY NIGHT THE MAIN UPPER LOW CENTERED OVER THE EASTERN
BERING SENDS A TROUGH AXIS INTO THE NORTHERN GULF OF ALASKA. THIS
ESSENTIALLY KEEPS THE SOUTHERN MAINLAND IN A SHOWERY PATTERN
THROUGH MID WEEK. MIXED PRECIPITATION ACROSS SOUTHCENTRAL MID WEEK
CHANGES OVER TO MAINLY SNOW WEDNESDAY INTO THURSDAY AS THE TROUGH
ADVECTS COLDER AIR FROM THE BERING. THURSDAY AND FRIDAY PRESENTS
THE BIGGEST WEATHER CHALLENGE AS TWO LOW PRESSURE SYSTEMS...ONE
ENTERING THE WESTERN BERING AND THE OTHER MOVING NORTH ACROSS THE
GULF...BRING GUSTY WINDS AND MEASURABLE PRECIPITATION THROUGH THE
SOUTHERN MAINLAND AND SURROUNDING WATERS.

KH

&&

.AFC WATCHES/WARNINGS/ADVISORIES...
PUBLIC...NONE.
MARINE...GALES...120 125 127 129 130 139 155 165 170-178 180 181
                 185
         STORMS...119
         HEAVY FREEZING SPRAY...181
FIRE WEATHER...NONE.

&&

SYNOPSIS AND MODEL DISCUSSION...
SOUTHCENTRAL ALASKA...
SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...
LONG TERM...