Scientific Forecaster Discussion
Northern Alaska forecast discussion
National Weather Service Fairbanks Alaska
431 am akst Thursday Dec 18 2014
Current model runs are generally similar out through Sat night in
the handling of the upper ridge moving slowly northward across
northern Alaska. The ridge will gradually weaken through Sat night
and be replaced by a weak low pressure field. Model solutions
differ after Saturday in the handling of several weak short wave
troughs embedded in this large area of low pressure.
18/0648z modis nighttime microphysics rgb image indicates
extensive areas of stratus over much of the interior...the
Seward Peninsula and areas just to the north. This is verified
by surface observation and by GOES infrared loop in areas which are not
obscured by higher cirrus. The lowest stratus...with areas
of flurries and fog...is over the interior. The stratus
is expected to break up slowly today as the upper ridge
Flurries and/or scattered snow showers are expected over the
Brooks range and North Slope...and over the North Slope tonight.
Operational GFS/European model (ecmwf) runs and the gefs/naefs and European model (ecmwf) ensemble
means indicating development over a strong storm over the western
Bering Sea Monday night which is prognosticated to recurve northward then
northwestward into the far western Bering Sea south of cape
olyutorsky on the siberian coast by Tuesday evening. Current GFS/European model (ecmwf)
verifying at 12z Tuesday are close on the low position...near
56n/174e. European model (ecmwf) central pressure...about 944 mb...is about 10 mb
lower than the GFS. After 12z Tuesday current forecasts indicate slow
filling of this system. East to southeast gales may occur over St
Lawrence Island and the central and southern parts of marine zone
pkz210 late Tuesday afternoon and Tuesday night out ahead of the
associated weather front. Winds are expected to decrease to
below gale force Wednesday as the front weakens and stretches out.
At this time...the strongest winds over the island are expected
to occur before the frontal snow band arrives.
Coastal hazard potential days 3 and 4...none
heavy freezing spray warning for pkz210.
Small Craft Advisory for pkz210.
Brisk Wind Advisory for pkz230.
Rf Dec 14