Scientific Forecaster Discussion
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Northern Alaska forecast discussion
National Weather Service Fairbanks Alaska
120 PM akdt Tue Mar 28 2017
Aloft at 500 hpa, the long wave trough that has been located over
eastern and central Alaska for the last several days continues to
move slowly to the west with its current axis along a Galena to
McGrath line. The axis will continue to move to the west and will
be along a Kotzebue to lower yk Delta line Wednesday and Thursday
and over the eastern Bering Sea Friday and Saturday. While the
upper level low moves to the west out of eastern and central
Alaska, an upper level ridge builds west out of the Yukon into
eastern and central Alaska.
A series of shortwaves will move north along the ridge over the
Alaska Range as well as eastern and central Alaska this week giving
rise to periods of light snow, flurries and much warmer
temperatures. The light snow south and east of Fairbanks will be
limited to generally less than one inch through Thursday morning
with drying southerly Chinook flow off of the Alaska Range. To the
north and west of Fairbanks the drying Chinook effect will be
limited. Expect 1 to 3 inches of snow to fall through Thursday
morning over the central interior west of Fairbanks west and the
western interior including McGrath, Bettles and Galena.
A strong shortwave will approach the Alaska Range Thursday and
will set up a moderate Chinook event Friday. Gap winds through
the Alaska Range passes will increase Thursday afternoon and as a
weak mountain wave sets up Friday morning, winds along the north
slopes of the Alaska Range may approach advisory levels.
The 12z model suite initialized well against the 12 surface
analysis and verified well against the 18z surface analysis. Model
spread remains reasonable in both the short range as well as the
mid range. Model spread increase rapidly by next weekend.
brisk Wind Advisory for pkz210-pkz220-pkz240-pkz245.