Gale Warning 30, NWS Fairbanks, AK

482 
FZAK69 PAFG 052345
OFFAFG
EXPERIMENTAL OFFSHORE WATERS FORECAST
NATIONAL WEATHER SERVICE FAIRBANKS AK
400 PM AKDT SUN AUG 5 2012

OFFSHORE WATERS FORECAST FOR THE US ARCTIC WATERS

SEA FORECASTS REPRESENT AN AVERAGE OF THE HIGHEST ONE-THIRD OF
THE COMBINED WIND WAVE AND SWELL HEIGHT. INDIVIDUAL WAVES MAY BE
TWICE AS HIGH.

PKZ599-061200-
400 PM AKDT SUN AUG 5 2012

.SYNOPSIS FOR ARCTIC WATERS...NO SYNOPSIS AS ALL AREAS ARE MOSTLY
ICE-COVERED.

$$


PKZ500-061200-
WESTERN US ARCTIC OFFSHORE-
400 PM AKDT SUN AUG 5 2012

NO FORECAST AS AREA IS MOSTLY ICE-COVERED.

$$

PKZ505-061200-
CENTRAL US ARCTIC OFFSHORE-
400 PM AKDT SUN AUG 5 2012

NO FORECAST AS AREA IS MOSTLY ICE-COVERED.

$$

PKZ510-061200-
EASTERN US ARCTIC OFFSHORE-
400 PM AKDT SUN AUG 5 2012

NO FORECAST AS AREA IS MOSTLY ICE-COVERED.

$$

AUG 12

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
427 AM AKDT SUN AUG 5 2012

.DISCUSSION...
UPPER AIR...A DEEP LOW NEAR 78N 160E EAST WILL CONTINUE TO DEEPEN
TO OVER THE NEXT 48 HOURS AS IT TRACKS TO THE NORTHEAST AND JUST
SOUTH OF THE POLE. ALL OF THE MODELS ALL HAVE AN ANOMALOUSLY DEEP
SUB 510 DM LOW AT 500 MILLIBARS BY 12Z TUE. A LOW THIS DEEP IN
AUGUST IS INDEED A RARE EVENT. STRONG WESTERLY FLOW ALOFT
ASSOCIATED WITH THE DEEP LOW WILL SINK SOUTH TO THE WESTERN AND
NORTHERN ARCTIC COAST TONIGHT AND ENCOMPASS THE AREA FROM ABOUT
THE ARCTIC CIRCLE NORTH BY MONDAY NIGHT. ELSEWHERE...A MUCH WEAKER
LOW CROSSING THE AK PENINSULA THIS MORNING WILL MOVE INTO THE GULF
OF AK TONIGHT AND ONLY VERY SLOWLY WEAKEN AND SHIFT EAST MID-LATE
WEEK. ANOTHER TROUGH IS EXPECTED TO DIG INTO THE NORTHEAST BERING
SEA BY THURSDAY AS IT ROTATES AROUND THE MUCH DEEPER HIGH ARCTIC
LOW.

SFC...LOW PRESSURE MOVED OFF THE RUSSIAN ARCTIC COAST LATE LAST
EVENING AND AT 12Z IS A 980 MB LOW 350 MILES NORTH OF WRANGEL
ISLAND. THE MODELS ARE NOW IN VERY GOOD AGREEMENT THAT THE LOW
TRACKS NORTH AND DEEPENS TO 970 MILLIBARS AS IT PASSES NORTH OF
80N TONIGHT AND THEN BECOMES VERTICALLY STACKED AND SLOWLY DRIFTS
TOWARD THE POLE. A BIG PUSH OF SIBERIAN WARM AIR IS PUSHING EAST
AHEAD OF THE LOW AND WILL QUICKLY BE FOLLOWED BY A STRONG COLD
FRONT. THE COLD FRONT WILL MOVE TO THE WESTERN ARCTIC COAST EARLY
THIS EVENING AND TO BARROW BY AROUND MIDNIGHT. BY MONDAY THE FRONT
WILL HAVE PUSHES EAST TO THE BEAUFORT SEA COAST AND WORKED SOUTH
INTO THE BROOKS RANGE. A RIDGE WILL BUILD INTO THE SOUTHERN
CHUKCHI SEA BEHIND THE FRONT MONDAY AND WILL COVER MUCH OF THE
CENTRAL AND EASTERN BERING SEA BY TUESDAY.

INTERIOR...FAIRLY QUIET WEATHER FOR THE INTERIOR THROUGH EARLY NEXT
WEEK WITH SOME MODERATION OF THE AIR MASS AND DRYING TOO.  STILL
SOME CYCLONIC FLOW ACROSS THE SOUTHERN INTERIOR/AK RANGE TODAY
AROUND THE AK PENINSULA LOW.  ISOLATED TO SCATTERED SHOWERS IN PARTS
OF THE SOUTHERN AND EASTERN INTERIOR WHICH WILL DISSIPATE BY THIS
EVENING. DRY WX JUST ABOUT ALL AREAS MONDAY WITH TEMPS NEAR TO A
LITTLE ABOVE NORMAL. THE FRONT ASSOCIATED WITH THE HIGH ARCTIC LOW
ADVANCES INTO THE NW INTERIOR LATE MON NIGHT WITH A CHANCE OF
RAIN. THE RAIN WILL LIKELY DIMINISH TO AN AREA OF SCATTERED
SHOWERS TUE AS THE FRONT MOVES INTO THE CENTRAL INTERIOR.

NORTH SLOPE...THE MOST ACTIVE AND CHANGEABLE WEATHER WILL BE ACROSS
THE AREA FROM THE BROOKS RANGE NORTH ASSOCIATED WITH THE DEEP ARCTIC
LOW. CLOUDS ASSOCIATED WITH STRONG WARM ADVECTION ARE NOW PUSHING
INTO THE BEAUFORT SEA. LOW END GALES SPREADING EAST TO BARROW
THIS AFTERNOON...BUT THE STRONGEST WINDS REMAINING OFFSHORE.
AN 08Z SCATTEROMETER PASS ALREADY HAD 30 KT WINDS IN MARINE AREA
PKZ225. THE WIND WILL TURN INTO THE WEST BEHIND THE STRONG COLD
FRONTAL PASSAGE TONIGHT. THE COMBINATION OF THE COLD AIR ADVECTION
AND STRONGER WIND ALOFT WILL LIKELY PRODUCE A WEST WIND OF 25 KTS
OR SO INTO TUESDAY. THE STORM SURGE MODEL HAS BEEN VERY CONSISTENT
NOW FOR SEVERAL RUNS WITH A 1.7 FT SURGE AT BARROW LATE TODAY AND
2.2 FT AT ICY CAPE. THE HIGHEST SEAS OF 10 TO 12 FEET WILL BE WELL
OFFSHORE WITH SEAS MORE IN THE 3 TO 5 FT RANGE NEAR SHORE. IT
CONTINUES TO LOOK LIKE AN EVENT THAT IS NOT QUITE WORTH OF A HIGH
SURF ADVISORY...BUT WILL REFRESH THE SPECIAL WEATHER STATEMENTS.
THE PROLONGED PERIOD OF WEST WIND EARLY NEXT WEEK WILL LIKELY
TRANSPORT SOME SEA ICE ALONG PARTS OF THE COAST...ESPECIALLY FROM
WAINWRIGHT TO BARROW.

WEST COAST...UPPER RIDGING BETWEEN THE HIGH ARCTIC AND AK PENINSULA
LOWS WILL KEEP MUCH OF THE WEST COAST DRY THE NEXT FEW DAYS.  THE
RIDGE DOES GET SQUASHED AND PUSHED SOUTH STARTING MONDAY AS THE
WESTERLY FLOW AROUND THE ARCTIC LOW BEGINS TO SINK SOUTH. THERE
WILL LIKELY BE SOME RAIN AND A MUCH COOLER AIR MASS PUSHING ACROSS
THE CHUKCHI SEA COAST SOUTH TO THE NORTHERN SEWARD PENINSULA LATE
SUN NIGHT AND MONDAY. THERE WILL BE A SHORT PERIOD OF SLIGHTLY
ELEVATED SEA LEVELS TODAY INTO THIS EVENING ALONG THE CHUKCHI SEA
COAST WITH SW WINDS OF AROUND 30 KNOTS AHEAD OF THE COLD FRONT.
WILL REFRESH THE SPECIAL WEATHER STATEMENT FOR THE CHUKCHI SEA
COAST FROM KIVALINA NORTH TO POINT HOPE. THE STRONGER WESTERLY
FLOW REMAINS NORTH OF THE AREA BEHIND THE FRONT AND THE WINDS AND
SEAS ARE NOT EXPECTED TO BE PROBLEMATIC.

IN THE MID-RANGE...MODELS ARE IN GOOD AGREEMENT FOR THE MIDDLE OF
THE WEEK WITH DEEP COLD LOW ALOFT NEAR 85N/155W...A RIDGE ALOFT FROM
MONTANA NORTH INTO THE WRN NWT AND A CLOSED LOW IN THE NRN GLF OF
ALASKA. BY LATE IN THE WEEK SHORTWAVE ROTATING AROUND THE ARCTIC LOW
DIGS A TROUGH BACK IN ALONG ABOUT 165W. HOWEVER...AS EXPECTED BY DAY
SIX...CONSIDERABLE DIFFERENCES IN TIMING AND INTENSITY. BY THE END
OF THE MID-RANGE...THERE IS SOME CONSENSUS TOWARD BUILDING A LOW
HEIGHT RIDGE OVR ERN MAINLAND ALASKA...A PLAUSIBLE OUTCOME WITH A
LONGWAVE TROUGH OVER THE BERING SEA. HENCE..WE HAVE TRIMMED BACK THE
PCPN RISK FOR NEXT WEEKEND EAST OF 148W.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...WINDS AND SEAS DIMINISHING
ALONG THE ARCTIC COAST BY WEDNESDAY AS THE HIGH ARCTIC LOW SLOWLY
FILLS.

&&

.FIRE WEATHER...CONTINUED QUIET. THE BEST CHANCE OF ISOLATED
THUNDERSTORMS WILL BE EAST OF THE BORDER TODAY. A FEW STRIKES
CAN'T BE RULED OUT RIGHT ALONG THE ALCAN BORDER...ESPECIALLY IN
ZONE 224. MIN RH'S WILL DROP TO 30-40 PCT IN THE CENTRAL AND
EASTERN INTERIOR VALLEYS...BUT THE WIND REGIME WILL REMAIN LIGHT.

&&

.HYDROLOGY...NO HYDROLOGIC ISSUES EXPECTED DURING THE NEXT FEW DAYS.
MOST INTERIOR RIVERS ARE NEAR OR BELOW SEASONAL NORMS.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY FOR PKZ210-PKZ220-PKZ225-PKZ230.

GALE WARNING FOR PKZ225-PKZ230-PKZ235.

BRISK WIND ADVISORY FOR PKZ235.

&&

CB/RT AUG 12