Gale Warning 62, NWS Fairbanks, AK

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
413 AM AKDT MON AUG 24 2015

.SYNOPSIS...
ALOFT...
A LONG WAVE PATTERN CURRENTLY CONSISTS OF A TROUGH OVER THE ALCAN
BORDER AND WESTERN CANADA...A RIDGE OVER THE N PACIFIC AND WEST
COAST OF ALASKA...AND ANOTHER LONG WAVE OVER KAMCHATKA AND THE NW
PACIFIC. THIS PATTERN BECOMES PROGRESSIVE WITH THE RIDGE BUILDING
OVER MAINLAND ALASKA THROUGH TUE AM THEN RETREATING SOUTH LATER IN
THE WEEK AS A SERIES OF SHORT WAVE TROUGHS MOVE EAST ACROSS
NORTHERN ALASKA. THIS WILL BRING WET SOUTHWEST FLOW TO THEW WEST
COAST OF ALASKA TODAY...INTO THE WESTERN AND CENTRAL INTERIOR AND
WESTERN ARCTIC TONIGHT...AND TO THE REMAINDER OF NORTHERN ALASKA
TUE. EXACT TIMING OF RAIN SUBJECT TO SLIGHT UNCERTAINTY...BUT HIGH
CERTAINTY THAT HEAVY RAIN WILL OCCUR BETWEEN NOW AND TUE NIGHT
ALONG THE WEST COAST AND WESTERN INTERIOR AND WED THU ACROSS THE
EASTERN INTERIOR.

A SHORT WAVE TROUGH FROM BARROW TO DELTA JUNCTION WILL MOVE TO
DEADHORSE TO NORTHWAY BY 4PM MON...THEN EAST OF THE ALCAN BORDER
MON NIGHT. EXPECT ISOLATED TO SCATTERED SHOWERS EAST OF THIS
TROUGH.

850 MB TEMPERATURES NEAR 0C WILL RISE 5C ALONG THE WEST COAST
TODAY...AND RISE BY 5C REMAINDER OF NORTHERN ALASKA TUE.

SURFACE...
HIGH PRESSURE NORTH OF THE ARCTIC COAST OF ALASKA WILL MOVE NORTH
TUE. A RIDGE OF HIGH PRESSURE FROM THE SE BERING SEA TO THE SE
INTERIOR OF ALASKA WILL PERSIST THROUGH TUE THEN RETREAT S ON WED.

A 989 MB LOW IN THE NW BERING WILL MOVE OVER THE CHUKOTSK
PENINSULA AS A 991 MB LOW BY 4PM MON...TO 200 NM WEST OF POINT
LAY AS A 992 MB LOW BY 4AM TUE...TO 200 NM NW OF POINT LAY BY 4PM
TUE...TO 200 NM NW OF BARROW AS A 991 MB LOW BY 4AM WED...AND TO
300 NM NORTH OF BARROW AS A 989 MB LOW BY 4PM WED. EXPECT EASTERLY
GALES JUST AHEAD OF THIS LOW AND SW GALES S AND SE OF THE LOW
TODAY AND TONIGHT. SINCE GALES WILL BE MINIMAL AND LAST ABOUT 24
HR AND INVOLVE WARM ADVECTION WE DO NOT EXPECT ANY COASTAL
FLOODING. WATER LEVELS WILL BE ELEVATED 2-4 FT OVER NORTON SOUND
SO MODERATE SURF IS LIKELY AND HIGH SURF IS POSSIBLE FROM LATE
TONIGHT THROUGH TUE NIGHT.

A TRAILING FRONT WILL MOVE ALONG THE DATELINE BY 3PM MON...TO
WAINWRIGHT TO ST MATTHEW ISLAND BY 4AM TUE...AND THEN MOVING
EAST TUE. A WARM FRONT STRETCHING SE FROM THE LOW WILL MOVE ALONG
THE WEST COAST OF AK BY 4PM MON...FROM WAINWRIGHT TO MCGRATH BY
4AM TUE....TO DEADHORSE TO FAIRBANKS BY 4PM TUE...AND THEN
CONTINUING EAST. WILL SEE WIDESPREAD RAIN BETWEEN THE WARM FRONT
AND TRAILING FRONT. EXPECT 1 TO 3 INCHES OF RAIN ACROSS THE WEST
COAST AND WESTERN INTERIOR THROUGH 4AM WED WITH THE HEAVIEST
AMOUNTS ALONG SW FACING SLOPES OF ZONES 208 AND 217. THIS WILL
BRING LARGE RISES ON RIVERS ALONG THE WEST COAST AND WESTERN
INTERIOR STARTING TUE AND CONTINUING THROUGH LATE IN THE WEEK ON
LARGER RIVERS.

AN ARCTIC FRONT TRAILING THE LOW INTO THE SW BERING SEA WILL MOVE
TO A 993 MB LOW SOUTH OF CAPE NAVARIN BY 4PM TUE...WITH THE FRONT
MOVING TO DEADHORSE TO THE BERING STRAIT TO A 1008 MB LOW IN THE
GULF OF ANADYR BY 4PM WED.

&&

.DISCUSSION...
MODELS SIMILAR ON LARGE SCALE FEATURES THROUGH WED...THEN SEE
LARGER DIFFERENCES DEVELOPING LATE IN THE WEEK. SLIGHT DIFFERENCES
ON TIMING OF SHORT WAVES MOVING EAST ACROSS ALASKA FROM TUE ON.
AT THE SURFACE MODELS INITIALIZE WELL. DIFFERENCES IN SURFACE
PRESSURE OF THE LOW IN THE WESTERN BERING SEA START TO SHOW UP BY
4PM MON AS THE NAM IS 5MB DEEPER THAN OTHER SOLUTIONS. PREFER THE
GFS SOLUTION WHICH KEEPS THE LOW ON A TRACK SIMILAR TO THE NAM
BUT KEEPS THE PRESSURE BETWEEN THE NAM AND ECMF. THE GFS ALSO HAS
A TRAILING FRONTAL WAVE WHICH IS SIMILAR TO THE NAM BUT NOT AS
DEEP AS THE ECMF. PREFER THE GFS ON MOST OF THESE FIELDS.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...
SINCE GALES WILL BE MINIMAL AND LAST ABOUT 24 HR AND INVOLVE WARM
ADVECTION WE DO NOT EXPECT ANY COASTAL FLOODING THROUGH WED.
WATER LEVELS WILL BE ELEVATED 2-4 FT OVER NORTON SOUND SO MODERATE
SURF IS LIKELY AND HIGH SURF IS POSSIBLE FROM LATE TONIGHT THROUGH
TUE NIGHT. COULD SEE ELEVATED WATER LEVELS ALONG THE ARCTIC COAST
FROM BARROW WEST WED AND THU BUT DO NOT EXPECT FLOODING AT THIS
TIME.

&&

.FIRE WEATHER...
NONE.

&&

.HYDROLOGY...
EXPECT 1 TO 3 INCHES OF RAIN ACROSS THE WEST COAST AND WESTERN
INTERIOR THROUGH 4AM WED WITH THE HEAVIEST AMOUNTS ALONG SW FACING
SLOPES OF ZONES 208 AND 217. THIS WILL BRING LARGE RISES ON RIVERS
ALONG THE WEST COAST AND WESTERN INTERIOR STARTING TUE...AND
CONTINUING THROUGH LATE IN THE WEEK ON LARGER RIVERS. AT THIS TIME
DO NOT EXPECT FLOODING SINCE RAIN WILL BE OVER 36 HR OR MORE.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY FOR PKZ200-PKZ215-PKZ220-PKZ225-PKZ230-
PKZ235-PKZ240-PKZ245.

GALE WARNING FOR PKZ210-PKZ225.
&&

JB AUG 15