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Northern Alaska forecast discussion 
National Weather Service Fairbanks Alaska
1248 PM akdt Friday Sep 19 2014


Models...initialized well. Remain in good agreement in the short
term...Canadian progressing the system east a little slower than
the other models as they get into the midrange. Models are showing
a little more concensus on the system that moves into the
southeast interior Sunday as all of them are showing precipitation
making it as far west as Fairbanks. Showing similar trends from
the Middle Range on...but quite a bit of disagreement on the strength
of the ridge over the West Coast and the trough over the eastern
half of the state. Precipitation guidance is similar...but the NAM
is a little slower in bringing it into the interior...and has
lesser amounts. 500 hpa...536 dam closed low over the Nushagak Delta
will move south over the shumagin island by Saturday afternoon
then continue south to 45n 150w before turning back to the
northeast and moving to the northern Gulf of Alaska by Monday
morning. A 534 dam low over the northwest coast will remain
stationary through Saturday afternoon then work southeast over
Anaktuvuk Pass by Sunday morning...then move northeast over
deadhorse by early Monday...then continue northeast as it weakens.
The trough associated with the lows extends down the West Coast
today and will move slowly east to be over the middle Yukon valley
by Saturday afternoon...then lie from Nuiqsut to Manley Hot
Springs to Kenai by Sunday afternoon and from Barter Island to
Fort Yukon to Delta Junction to Seward by Monday afternoon. At
850 isotherm lies along the eastern Arctic coast to
Nuiqsut then southwest to the Brooks range and then west to
Kivalina then south along the coast today. It will lit from Barter
Island to Arctic Village to Tanana to Sleetmute and southwest by
Saturday afternoon. And Sunday afternoon it will move to lie from
MacKenzie Bay to Fort Yukon to Delta Junction then southwest.

Surface...a broad area of low pressure with a 990mb center over
southcentral Alaska will move north over the interior with the low
in the upper Yukon Flats by Saturday morning. The low will move
slowly east with the trough slowly dragging out of the area. A 986
mb low in the North Pacific will move into the Gulf of Alaska
Sunday and continue north to Prince William Sound by Monday
afternoon. A weather front associated with the low will spin up
over Southeast Alaska Sunday night and Monday. Ridge of high
pressure building over the central Bering seas will move over the
eastern Bering Sea tonight and over the Bering Strait by Saturday
night...then working inland to the middle Yukon valley and over
the Northwest Arctic by early Monday morning.

Arctic coast and plain...a messy mix of low clouds...fog...snow
..freezing drizzle...Rain...wind...and cooling temperatures over
the Barrow area will spread over most of the Arctic coastal areas
at some time this weekend...but the Barrow area will see the worst
of it. The GOES MVFR probability 4km at 19/1745z shows high
probability of MVFR over vast areas of the Arctic coast and
offshore areas. The IFR product is not showing very much...but it
does have areas over the Northwest Arctic coast. Looking back
overnight the areas have not changed much...and do not expect they
will. The npp viirs day night band at 19/1718z confirms cloud
cover over the area and shows a nice clear to partly cloudy area
over the northeast Arctic offshore area. Gradient has tightened up
and winds have increased over the coastal areas to 15 to 25 miles per hour
gusting near 40 miles per hour. Winds will trend slowly down tonight and
Saturday as the gradient relaxes. Inland areas will continue to
see much lighter winds in the 5 to 15 miles per hour range. Do not expect any
accumulation of the wet snow...but if we have any it should melt
off pretty quick. Temperatures will continue a slow downward trend
inland...while temperatures along the coast will not change much
due to the open water in the area.

West Coast and western interior...coastal areas are pretty
nice...with the exception of some strong winds through the Bering
Strait. Inland the trough of low pressure has set up over the
middle and lower Yukon valley and the upper Kobuk and Noatak
rivers as expected. Rain/showers will continue over the area
tonight and begin tapering off toward morning as it moves east and
gets pulled into the low over the interior. Rainfall amounts up to
one half inch today in the middle Yukon valley. Patchy fog may be
a problem in some areas but not expecting visibility to remain
down for extended periods of time. A high will build in over the
Bering Strait this weekend and conditions will improve...but
expect cooler conditions over the area with cloudy conditions in
the coastal areas.

Interior...ridging from the east kept the clouds ot of a large
part of the interior last night...but that will all change tonight
as clouds will increase as the low moves north into the interior
spreading rain into the area overnight. Rain will begin overnight
and continue into Sunday morning. Rainfall amounts still looking
to be up to one half inch through Sunday morning. Not looking for
much wind with the rain...but some winds gusting to 20 miles per hour over
the hills would not be surprising. There is a potential for some
flurries at higher elevations on Sunday evening...but no snow on
the horizon at this time.


Coastal hazard potential days 3 and 4...none.


Hydrology...rivers continue to fall.


Fire weather...none.


Afg watches/warnings/advisories...

Small Craft Advisory for pkz210-pkz220-pkz235.

Gale Warning for pkz240-pkz245.

Heavy freezing spray for pkz510.



Sdb Sep 14

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