Scientific Forecaster Discussion
Northern Alaska forecast discussion
National Weather Service Fairbanks Alaska
206 am akdt sun Sep 21 2014
models continue to display reasonable run to run continuity in the
short term and continue to initialize well. Significant run to run
differences as well as model to model differences arise in the
middle term and extended term solutions however the spread is less on
todays suite of models than yesterdays.
Aloft...at 500 hpa...a 526 dam closed low 200 nm northwest of
Wrangell Island continues to dig south and east to be over
Wrangell Island as a 520 dam low Monday morning with a deep trough
extending east to Barrow and then southeast to parc and then
southward into Prince William Sound. A 554 Dam Ridge centered over
Bristol Bay builds over the eastern Bering Sea. The upper level
low over Wrangell Island moves east to be located near pawi Monday
afternoon as a 522 dam low as the ridge over the eastern Bering
Sea is suppressed to the south as a short wave rotates around the
upper level low near pawi. The upper level trough over the eastern
interior Monday sweeps east into Canada Tuesday. 850 mb
temperatures will continue to drop over northern Alaska. 850 mb
temperatures over Fairbanks will drop from around 1 above on the
Saturday afternoon sounding to around 1 below Sunday morning and
to around 4 below Monday morning. Lingering rain showers Sunday
night and Monday morning in the interior may mix with snow.
Arctic coast and plain...low ceilings fog and snow continue east
of Barrow while precipitation is tapering off over the western Arctic
coast. Snow will taper off to scattered snow showers from west to
east over the Arctic coast today however more snow will move in
over the western North Slope tonight as models continue to
indicate a 1000 mb low moving east out of the chukotst peninsula
will deepen to around 994 mb and be located near Point Lay by
Monday morning. The low will is prognosticated to hug the coast and
deepen to around 992 mb and be located over Barrow Monday evening.
Guidance continues to indicate a compact low with gale force winds
likely on the back side of the low as it pulls to the northeast.
The low will be moving quickly so not expecting any high surf
issues along the northwest coast as both time duration and fetch
will limit coastal hazard potential. Expect wind driven snow
Monday over the western North Slope and Monday night and Tuesday
for the central and eastern North Slope as the low moves northeast
along the coast.
Interior...first front is currently draped over the central
interior along a pabt to pamc line at this time and will continue to press
eastward today and will bring with it cooler temperatures. Areas
of rain ahead of the front will taper to scattered rain showers
over the central interior today. Remaining rain showers may mix
with snow tonight over the interior. The front racing across the
North Slope Monday and Tuesday will also impact the West Coast
Monday and western interior Monday evening. Expect rain showers
along the West Coast Monday and rain showers to transition to
snow showers Monday night in the western interior the front moves
into the central interior Tuesday and into the eastern interior
Tuesday evening with scattered rain and snow showers expected
there as well with minor accumulations possible in higher terrain.
Coastal hazard potential days 3 and 4...none
ongoing rain event winding down with storm total rain fall in the
one quarter to one half inch range over the central interior
however no significant Hydro issues are expected.
Small Craft Advisory for pkz235.
Gale Warning for pkz240-pkz245.
Ccc Sep 14