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fxak69 pafg 242131 

Northern Alaska forecast discussion
National Weather Service Fairbanks Alaska
131 PM akdt Fri Mar 24 2017


Models...big changes in guidance since yesterdays (23/12z)
solutions. Short term guidance remains similar to yesterday, but
beyond Sunday there are big changes as they spin some
precipitation north into the central and eastern interior. The GFS
is much more aggressive at this time in bringing the snow into
the area and keeping it around. Big picture the models are still
reorienting the longwave trough over the eastern Bering Sea and
Chukchi Sea midweek. The 24/12z solutions initialized well with
the 24/18z surface analysis. Precipitation guidance continues to
be lacking with the GFS providing too much coverage in the short
term. The sref solution has been performing well with the
precipitation the last week so we will continue to use it for the
first 48 hours. 500 hpa...long wave trough persists over the eastern
half of the state through Saturday then starts retrograding to the
west, but not as far as previous solutions, and will settle over
the West Coast/western interior midweek. A 481 dam low near 80n
180 will move east to 80n 140w by Sunday morning, then southeast
to Banks Island by Monday night. A shortwave associated with the
low will move over the western Arctic Saturday afternoon and
continues east across the Arctic over Canadian waters by Monday
morning. A 515 dam low will develop over the Copper River basin
Saturday morning and slowly drift southeast to be over Cook Inlet
by Monday morning at 513 dam, then moves west. Ridging over the
eastern Bering Sea will persist into Sunday, then the 533 dam high
over the central Bering Sea is cutoff from the North Pacific
ridge and drifts west. A weak ridge with 518 dam heights will
build over the Chukchi Sea late Sunday and move east over the
Arctic coast to MacKenzie Bay by Tuesday morning. At 850
hpa...weak warm air advection continues, with temperatures around
-15 warming to around -10 by Wednesday.

Surface...ridging persists from Siberia over the chukotsk
peninsula to the Seward Peninsula and then east over the Brooks
range persists, but will weaken tonight. A 993 mb low in the high
Arctic will slowly move east to the high Canadian Arctic with a
broad area of lower pressure remaining over the Arctic east of the
dateline. A 1000 mb low will develop in the northern Gulf of
Alaska and dissipate Saturday night. A 1024 mb high will develop
over Siberia and move over the Chukchi Sea by Sunday morning with
ridging extending east over the Arctic coast. A 985 mb low will
move out of the northeast Pacific Sunday into the southeast Gulf
of Alaska and move to the northern Gulf by Tuesday morning as it
weakens to 994 mb. A 965 mb low south of the western Aleutians
will persist with a 978 mb low moving to the central Aleutians by
Sunday morning the lows then merging into a single low over the
central Aleutians Monday.

Arctic coast and Brooks range...high pressure will continue to
hold over interior Alaska and this is producing a fairly zonal
flow across the Arctic through Saturday when a stronger high will
develop over the Chukchi Sea and push the low pressure to the east
a bit. For tonight flurries or some light snow, but not much
accumulation. As the high builds over the Chukchi Sea the flurries
will end over the northwest coast and be mainly east of Barrow on
Sunday. Winds mainly west at 10 to 20 mph. East of deadhorse
expect some gusty winds to 35 mph at times with blowing snow.

West Coast and western interior...npp-viirs sport 24 hour
microphysics rgb at 24/1535z shows quite a bit of stratus over the
Chukchi Sea, Kotzebue Sound, and the eastern Bering Sea. Does not
appear to be dissipating very fast under the ridge, so not
expecting much change tonight. A few flurries and periods of
stratus and fog for the coastal areas, but difficult to say just
where the stratus will be of significant impact. Do not expect any
snow accumulation. Winds 5 to 15 mph from the northeast to east
and that may help push the stratus offshore south of the Bering
Strait, while creating problems north of the Bering Strait along
the Seward Peninsula coast.

Central and eastern interior...mainly clear with the exception of
the upper Tanana Valley where it will be mostly cloudy with some
light snow or a few flurries through late Saturday before ending.
No significant accumulation is expected. Temperatures will
continue to be cool at night falling to -10 to -30, then
recovering during the day to 10 to 25. Winds will continue to be
light and variable.


Afg watches/warnings/advisories...

Brisk Wind Advisory for pkz230-pkz235.


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