Area Forecast Discussion
Issued by NWS Fairbanks, AK

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29
000
FXAK69 PAFG 192155
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
155 PM AKDT Tue Sep 19 2017

.DISCUSSION...

Models...Continues to be good agreement in the short term big
picture, with divergence beyond 48 hours. In the extended periods
there is better agreement today than in previous solutions. They
initialized well against the 19/18Z surface analysis. For the
short term will utilize a equal blend for most elements with a
lean toward the NAM precipitation solution again today. once again
the biggest challenge will be precipitation type in this
transition period.

Aloft at 500 hpa...Main longwave trough has shifted east a bit to
lie over 165W today, and will slowly continue to work its way
east tonight. A shortwave moving through the trough lies from
Wainwright to Norton Sound and will move northeast over the
Beaufort Sea by Wednesday afternoon. A second shortwave will move
over St Lawrence Island this evening and moves east across the
southwest mainland then south of the Alaska Range Wednesday. A 556
dam high over the southwest Yukon Territory will move southeast
as a ridge axis that lies from the northeast Pacific over Dutch
Harbor rotates east over Bristol Bay by Wednesday afternoon, and
over southcentral Alaska by Thursday morning. A 546 dam low will
develop over the Bering Strait Wednesday afternoon and move over
the Nulato Hills Thursday morning at 544 dam with troughs
extending northeast over Deadhorse, east over Fairbanks, and
southwest over the Pribilofs. The ridging over Southcentral Alaska
will continue to rotate east Thursday to the AlCan Border, then
over the southeast Panhandle Thursday night. At 850 hpa...Zero
isotherm lies Demarcation Point to Fairbanks to King Salmon this
afternoon, and will move to lie from Old Crow YT to Anchorage to
Nunivak Island by Wednesday afternoon. The a patch of -10
Temperatures is over the northwest Arctic Coast today and will
slide to the northeast Thursday and slowly warm.

Surface...Dynamic pattern the next 24 hours as trough over the
eastern half of the state moves out, weak ridging is building in
over the Alaska Range and Central Interior this evening then
breaks down as a low is moving over Norton Sound this afternoon
and will work its way over the Nulato Hills tonight. A the low
weakens, it will move over Ruby by Wednesday afternoon, and into
the Upper Tanana Valley by Thursday morning. High pressure is also
building east across the Chukchi Sea this afternoon and a 10125
mb high will develop south of Point Barrow tonight. The high will
move to 100 nm north of Deadhorse by Thursday morning with high
pressure extending west to the Chukchi Sea, then south over the
Bering Strait. High pressure will persist over the Arctic Coast
until Friday, then be pushed offshore as low pressure expands over
mainland Alaska.

Arctic Coast and Brooks Range...A mix of rain and snow changing to
mostly snow tonight, but no significant accumulation. Snow
tapering off Wednesday morning, then some clearing on the
northwest Arctic Coast. For Point Barrow east it will remain
cloudy with low ceilings and an occasional flurry. Offshore flow
on the northwest coast, with onshore flow to the east. Winds 5 to
20 mph with the strongest winds over the eastern Arctic Coast.
Temperatures warming into the mid to upper 30s during the day, and
in the 20s at night.

West Coast and Western Interior...Fast moving system impacting the
Norton Sound region will move inland and lose most of its energy
this evening. Rain will continue through the evening, then some
clearing toward morning in the coastal areas. Rivers continue to
fall. Patchy fog along the rivers in the morning may impact
visibility for a few hours. Cooler temperatures with locations
from Nome north, and not on the coast, seeing freezing
temperatures overnight. Additional rainfall tonight will be 0.25
inch or less. Wind direction will be all over the dial with wind
speeds 5 to 20 mph tonight, slightly high on the outer Capes.

Central and Eastern Interior...Cloudy, but some breaks in the
evening over the Central Interior, then clearing to partly cloudy
early tomorrow. Some light rain mainly north of Fairbanks will be
tapering off overnight. Increasing clouds Wednesday afternoon with
rain developing across the area in the evening. Expecting some
snow over Denali NP Wednesday night and Thursday with 2 to 4
inches of accumulation in the passes along the park road. Also
expect some snow along the Parks Highway and Richardson Highway,
but expect it to slowly melt as it falls with road temperatures
still above freezing. Snow along the Dalton Highway will be
north of Coldfoot. Cooler air moving over the area will bring
potential for snow at higher elevations, so some areas in the
White Mountains could also see a dusting. Patchy fog along the
rivers and near lakes may impact visibility for a short time in
the morning. Light winds will be variable, but mainly from the
northwest by Wednesday afternoon.

&&

Coastal Hazard Potential Days 3 and 4...None.

&&

.Hydrology...Rivers continue to run high, but are slowly falling
in most areas so will cancel the existing Flood Advisory. Rivers
will remain high through the week, and there may be a minor crest
associated with rain from today and tonight, but it is not
expected to create any additional problems.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...

Small Craft Advisory for PKZ210.

&&

$$

SDB SEP 17


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.