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Northern Alaska forecast discussion...corrected 
National Weather Service Fairbanks Alaska
211 am akdt Wednesday Oct 22 2014

Corrected spelling

Discussion...

Models...very good run to run continuity for the short term. European model (ecmwf)
and GFS are not showing the significant divergence that they had
yesterday toward the end of the Middle Range. Latest run initialized
well against the 06z surface analysis.

Aloft at 500 hpa...512 dam low over Bristol Bay yesterday will be
absorbed by a 516 dam low over the southern Gulf of Alaska this
morning...then move south. A weak trough of low pressure over the
interior will move east as a shortwave ridge over the dateline
this morning moves over the West Coast later this evening...then
over the central interior late Thursday evening...and into Canada
late Friday evening. A weak trough that extends from a low in the
high Canadian Arctic southwest over the near shore Arctic waters
will remain stationary with a 529 am low developing north of
Barrow by Thursday morning. A trough extending south from a low
north of the sea of okhotsks will move to the dateline by Thursday
morning...then to the West Coast by late Thursday night...then
work its way across the state through Saturday evening as it
weakens. A relatively fast zonal flow will develop south of the
low in Siberia and extend from eastern China into the central
northwest territories...persisting into the weekend.

On the surface...a 1038 mb high near 79n 172w will wobble around
a little bit as it weakens to 1033mb then moves west late Thursday
night. Broad area of low pressure that extends north over Mainland
Alaska from 976mb low in the southern Gulf will slowly be pushed
southeast as weak ridge of high pressure moves over the West Coast
this evening and into the interior by late Thursday evening as it
lies southwest to northeast across the Mainland. A 1006 mb low
will develop over Prince William Sound late Thursday night and
persist into Saturday before moving southeast and dissipating. A
frontal system extending south over the eastern Bering Sea from a
994mb low in Siberia will move to the dateline by early
Thursday...then extend from the low in Siberia over the chukotsk
peninsula to St Matthew island then southwest by Thursday morning
and moves to the western interior by Friday morning as it falls
apart.

Arctic coast and Brooks range...strong winds continue...but they
will be diminishing from the west today and tonight. The wintery
mix of weather of the past week will continue for another
day...but conditions will be improving as we get into the weekend
and flow turns offshore with trough of low pressure developing
over the plains and coast. Until then flurries...blowing
snow...occasional freezing drizzle...and areas of fog will
continue to cause issues. Temperatures will remain steady in the
coastal areas with slight cooling in the inland areas and Brooks
range.

West Coast and western interior...pretty quiet today in advance of
the weather system that will spread snow over St Lawrence Island
tonight and into the West Coast early Thursday morning...and to
the western interior Thursday afternoon. Most areas can expect 1
to 2 inches of snow with the system. The lower Yukon Delta may see
the snow mix or turn to rain during the middle day hours. Winds north
at 5 to 15 miles per hour today becoming southeast to south later
today...then west after the front passes. Some slight warming
south of the Seward Peninsula as the ridge moves over the area in
advance of the front...then temperatures cool slightly and remain
steady through the weekend.

Central and eastern interior...some clearing today for most of the
area. Weak front will push up over the far southeast interior and
spread some flurries over the area into the afternoon before
moving into the Yukon territory. Winds northeast 5 to 15 miles per hour
becoming light. Clearing tonight as weak high pressure moves over
the area. Dissipating front tries to make it into the interior
late Friday night...but it will have lost most of its energy by
then so looking like nothing more than a dusting of snow with the
first wave. Temperatures trending down and with the clearing skies
they should bottom out with lows Thursday nearing the single
digits and on Friday lows near zero for many areas.

&&

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

&&

Afg watches/warnings/advisories...

Heavy freezing spray warning for pkz225-pkz230-pkz235-pkz240-
pkz245.

Small Craft Advisory for pkz220-pkz225-pkz230.

Gale Warning for pkz235-pkz240-pkz245.

&&

$$

Sdb Oct 14

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