Scientific Forecaster Discussion
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Northern Alaska forecast discussion
National Weather Service Fairbanks Alaska
538 am akdt Fri may 26 2017
the active pattern that has been seen over northern Alaska the
past few days is currently on a downward trend. The models are in
good agreement out through the weekend into early next week.
Aloft, at 500 hpa, a 524 dam low currently sits just north of the
Bering Strait with a 529 dam low just south of Barrow. The low
currently south of Barrow will move to just north of wrangel
island by Saturday morning and will then continue moving to the
north and west. The low currently north of the Bering Strait will dive
south to the Kuskokwim Delta by early Saturday morning, and to
Bristol Bay by early Sunday. An upper level ridge will begin
pushing northward along the Canadian border Sunday. The models
paint the picture that an upper level ridge will build west across
the state early next week with the ridge axis oriented east to
west just north of the Alaska range; however, there are some
difference in the details of this at this time.
At the surface, a 999mb low currently 100 nm north of Barrow will
move to 375 nm northwest of Wainwright by Saturday morning and will
continue to move to the northwest. A 1002 mb low 100 nm west of Point
Hope will weaken in place today. A 1004 mb low just south of St.
Lawrence Island will move to just south of Tin City by this
evening and will then weaken in place. A thermal trough will
develop just north of the alaksa range on Sunday.
North slope: snow in the Barrow area will taper off this morning
as a low north of Barrow rapidly moves to the northwest. Skies to
the east of Barrow are relatively clear. With the low moving
northward, expect decreasing cloud cover from Barrow west today.
Southerly winds are expected along the coast through Saturday
afternoon. This should limit the potential for low visibility due
to fog. Winds will turn westerly Saturday afternoon across the
North Slope. The pressure gradient will tighten on Sunday along
the Beaufort Sea coast as a sfc trough develops north of the
Brooks range, this will likely result in gusty wind near
Kaktovik, where gusts around 45 mph are not out of the question.
Central and eastern interior: a look at webcams in Denali National
Park this morning shows that snow has redeveloped. Since the snow
is still ongoing, I made the decision to push the end time of the
Winter Weather Advisory back by 4 hours. Some patchy fog has
developed along the Tanana river near Fairbanks early this morning;
however, any fog that is out there will dissipate by mid morning.
Elsewhere, scattered showers are expected today around the
interior. The models are showing an area of negative lifted
indices combined with enough cape to result in a few isolated
thunderstorms in the upper Koyukuk valley this afternoon,
especially near Bettles. Chances for showers become more isolated
on Saturday. With a thermal trough developing on Sunday north of
the Alaska Range expect gusty gap winds to develop Sunday
afternoon and evening. A warming trend is expected Saturday
through Wednesday of next week. By Wednesday of next week high
temperatures in the Fairbanks area will be in the low 70s.
West Coast and western interior: scattered to numerous showers
today. The precipitation type will be mostly snow in the morning;
however expect it to change over to rain in most locations by the
afternoon as the snow level rises. Tomorrow numerous to scattered
showers are again expected. There is also the potential for some
isolated thunderstorms along the coast. Things look to dry out
early next week as the upper ridge builds west, particularly for
the western interior.
a general warming and drying trend is expected to begin on
Saturday for the interior. Some isolated thunderstorms today in
the upper Koyukuk valley. A thermal trough will develop north of
the Alaska Range Sunday. As the thermal trough develops, southerly
gap winds will increase through Alaska Range passes Sunday
afternoon and evening.
as temperatures warm this weekend the recent heavy snowfall in the
Alaska Range will begin to melt. This will cause increased flow in
rivers and streams that drain the Alaska Range late this weekend
into early next week. Breakup continues for the rivers north of
the Brooks range with no known issues at this time.
Winter Weather Advisory for akz225.