Scientific Forecaster Discussion
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Northern Alaska forecast discussion
National Weather Service Fairbanks Alaska
432 am akdt sun Apr 30 2017
the models remain in good agreement in the short term. Currently
aloft, a 515 dam low at 500 mb sits just east of Adak while an
upper level ridge stretches from the eastern Yukon territory into
the Beaufort Sea. The aforementioned low will slowly push
eastward and will make it to the northern Gulf of Alaska by
Wednesday. Upper level ridging will looks to build over back
again over northern Alaska next weekend, although at this point
there are some differences in the models that far out. At the
surface, a broad area of low pressure sits in the southern Bering
Sea with a 986 mb low currently positioned about 200 nm west of
St. Paul island, while a 1030 mb high is situated in the Beaufort
Sea. The surface low complex will slowly move to the east into the
Gulf of Alaska by midweek.
Central and eastern interior: a surface weak surface trough
stretches from Northway to Nenana. Some isolated to scattered
high based shower are expected near the trough today primarily in
the afternoon and evening hours. On Monday the flow becomes more
southerly. This will help increase winds through the passes of the
Alaska Range for Monday into Tuesday. Current thinking it the the
winds will be below advisory criteria. The downslope flow on
Monday will help to keep most of the showers north of Fairbanks.
Late Tuesday the pressures gradient across the interior as a
surface low moves into the northern Gulf of Alaska. As the
pressure gradient tightens gusty northeasterly winds will develop
across the interior. A front associated with the surface low will
also bring showers to the interior on Wednesday.
West Coast and western interior: some isolated to scatted showers
today, primarily in the afternoon and evening in the western
interior and the Yukon Delta. On Monday afternoon and evening the
GFS is showing negative lifted indicies along with surface based
cape values between 100 and 400 j/kg stretching from the Yukon
Delta into the western interior. This may result in a few
lightning strikes in addition to any showers. Chances for
precipitation in the Yukon Delta and the lower Yukon valley
increase on Tuesday as low moves east from the Aleutians into the
Gulf of Alaska.
North slope: relatively quiet weather persists across the North
Slope. The biggest issue will be fog, flurries and low clouds
which will persist today and tonight.
Fire weather...no real concerns right now as far as fire weather
GOES. Winds in the Alaska Range will increase Monday. This will be
accompanied by a decrease in relative humidity values.
Small Craft Advisory for pkz210.