Gale Warning 99, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
613 AM AKDT Fri Aug 2 2019

.DISCUSSION...

Synopsis...Weather system moving over the West Coast this morning
will spread rain over most of the forecast area by this evening.
Rainfall amounts by Sunday morning will range from 0.5 to 3.0
inches for much of the area with local amounts to 4 inches in the
Norton Sound Region. Most, if not all, of the active fires will
receive a Wetting Rain by Sunday morning.

Models...02/00Z Solutions are in good agreement for the short
term, and today it looks like there have only been some minor
changes since the 01/12Z solutions. Still going to lean toward
continuity and make only minor adjustments to the current
forecast database. Solutions diverge beyond 60 hours or so with
significant differences in feature positions. Initially major
features have similar heights, and locations. Zonal flow will
bring several shortwaves across the area through Sunday morning,
but timing is different with all the solutions. Convective
indicies are not very impressive, and with westerly flow
convection is generally limited, but would not be surprised by an
embedded thunderstorm. Going with the NAM primarily with a kick
from the SREF for precipitation location. QPF will be a blend of
available solutions leaning toward the GFS which is currently
showing precipitable water values of 1 to 3 inches over most of
the forecast area for several periods through Sunday morning.
Winds primarily NAM.

Aloft...At 500 hpa...Broad troughing over the Arctic with a 528
dam low over the Central Beaufort Sea and a 532 dam low 600 nm
north of Point Barrow. Troughing extends southwest to a 548 dam
low over Siberia, and a 550 dam low is moving east over the Gulf
of Anadyr. Ridging extends northeast out of the North Pacific over
most of mainland Alaska with 580 dam heights over the Alaska
Peninsula and 558 dam heights over the Brooks Range. By Saturday
morning the troughing over the Arctic will shift offshore with the
low over the Beaufort Sea moving north into the high Arctic, and
the low north of Point Barrow wrapping back around to the
southwest to 400 nm northwest of Point Barrow. Troughing extends
southwest to the low that was over the Gulf of Anadyr, and is now
moving over the Bering Strait at 538 dam, and further southwest
to a 566 dam low over Shemya. The ridging over the state enhances
a bit as a 591 dam high develops 300 nm south of Seward and 561
dam heights push over the Brooks Range. By Sunday morning ridging
over the state flattens out as the low over the Bering Strait
moves over the Eastern Arctic Coast and starts to merge with the
troughing over the Arctic and the strong shortwave associated with
it moves to lie from Deadhorse to Minchumina. Ridging persists in
the Northeast Pacific as the high builds to 593 dam. The strong
shortwave will move east of the state Sunday afternoon with weak
ridging building in over the West Coast behind it and rotating
over the Interior Sunday night. At 850 hpa...Temperatures range
from -3C over the Northwest Arctic Coast to +9C over the
Southeast Interior this morning. 0C isotherm lies along the crest
of the Brooks Range, and by Saturday morning it will be north of
the Arctic Coast as temperatures across the state rise to just
above 0C over the Arctic Coast to +10C to +12C in the Lower Yukon
Delta and along the north slopes of the Alaska Range.

Surface...992 mb low near the Gulf of Anadyr will move northeast
to the Bering Strait by Saturday morning, and over Oliktok on the
Eastern Arctic Coast by Saturday night. Rain is spreading east
into the Interior already this morning and will continue into
Sunday as a strong southwest fetch of moisture persists. Strong
southeast winds will persist into the coast as well with seas
build and storm surge of 4 to 8 feet for coastal areas south of
the Bering Strait. A 1033 mb high will build over the Northeast
Pacific, 400 nm south of Seward, by Saturday morning. The low will
move to the southern Beaufort Sea by Sunday morning at 996 mb. The
warm front associated with the low will move northeast across the
state today, with the cold front moving to the West Coast Saturday
morning, and by Sunday morning it will lie from MacKenzie Bay to
Old Crow YT to Ambler and west. Weak high pressure will build in
north of the Alaska Range Sunday night.

Arctic Coast and Brooks Range...Southwest to west winds this
morning will snap around to northeast to east as the low that
moved over the coast yesterday moves north in the Beaufort Sea,
and the low near the Gulf of Anadyr moves northeast across the
Chukchi Sea Saturday morning. Temperatures warming cold air aloft
shift back to the north.

West Coast and Western Interior...Rain will continue with winds
increasing overnight. High Surf conditions developing late this
evening. Coastal Flood Advisory, Flood Watch, and High Surf
Advisories have been issued. Go to www.weather.gov/fairbanks for
the latest information. A strong southwest fetch developing and
feeding moisture into the West Coast. Persistent southwest winds
will build seas south of the Bering Strait. As the low moves
northeast across the Bering Strait winds on the back of the low
will produce high surf along the Chuckchi Sea Coast and in
Kotzebue Sound. Southwest winds increasing today to 10 to 25 mph
with gusts to 45 mph in the Norton Sound Region. Temperatures
slightly warmer as the southwest fetch bring warmer air northeast
into the area.

Central and Eastern Interior...Showers today as the front stalls
in the area. Then some clearing this evening. More rain on the way
Friday that will continue through Sunday morning with 0.5 to 1.5
inches of rain expected over much of the Central Interior, and
most of the Eastern Interior. Locally some areas in the Central
Interior may get around 2.0 inches of rainfall. Southwest to west
winds mainly north of Fairbanks at 5 to 15 mph gusting to 25 mph,
while from Fairbanks south winds will be 5 to 10 mph gusting to
15 mph. Temperatures cooler through the weekend.

&&

Coastal Hazard Potential Days 3 and 4...Elevated surf Sunday into
Monday along the Eastern Arctic Coast.

&&

Extended forecast for days 4 to 7...A brief respite from the rain
on Sunday night, Monday another system will move across the state
spreading rain to most if not all of the forecast area.
Temperatures cooling a couple degrees Monday, then warming a
couple degrees Tuesday and Wednesday.

&&

.Fire Weather...Another round of Wetting rain today as a weather
system moves across the state. Wetting rain again Saturday and
into Sunday before it tapers off. Wetting Rain will fall on all
the current fires by Sunday morning. Southwest winds generally
gusting to 15 mph will become southeast gusting to 20 mph as the
front approaches, then southwest gusting to 25 mph as the front
moves through the area. Cooler temperatures with above 50 percent
Relative Humidity values through the weekend. Excellent overnight
Relative Humidity recover continues.

&&

.Hydrology...With heavier rains expected the next couple of days
rivers will be on the rise. Rainfall amounts will 0.5 to 2.0
inches or more by Sunday morning. Travelers should be cautious
near all waterways. For the latest river forecasts go to
www.weather.gov/aprfc.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...

High Surf Advisory for AKZ207-AKZ209-AKZ210-AKZ213.

Coastal Flood Watch for AKZ211-AKZ212-AKZ214.

Flood Watch for AKZ211.

Small Craft Advisory for PKZ215-PKZ220-PKZ225-PKZ230-PKZ240.

Gale Warning for PKZ200-PKZ210-PKZ245-PKZ510.

&&

SDB AUG 19