Small Craft Advisory 168, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
153 PM AKDT THU SEP 22 2016

.DISCUSSION...
The 12 model suite initialized well against the 12z analysis and
verified well against the 18z analyses. Model spread is minimal
in the short range and reasonable in both the mid range and long
range. The model suite continues to indicate a stormy week in the
Bering Sea next week with a series of three storms likely to
impact the west coast through next Saturday.

Aloft, at 500 hpa a long wave trough with a 507 DAM low near
Wrangel Island and a 527 DAM low near St Paul Island will continue
to drift to the east as the low near St Paul Island moves north
and east to be located over Galena this evening and over Barter
Island Friday morning. This upper level low and attending strong
shortwave will provide upper level support for a deepening surface
low moving north out of the interior tonight.

On the surface...a 975 mb low currently Just west of Fairbanks
will move north and west tonight and will be located near Ambler
Friday morning with a secondary low around 978 mb near Demarcation
Point. The low over Ambler weakens into a trough that rapidly
moves north and east with the low that was near Demarcation Point.
This low combined with a favorable upper level environment is
expected to bring significant rain in the one half to one inch
range over the western interior with lesser amounts in the central
interior through Friday and will bring significant snowfall over
the central and eastern Brooks Range and interior portions of the
North Slope beginning tonight and continuing through Friday
evening. Storm total snowfall is expected to be 4 to 8 inches in
these areas.

Extended Outlook...Busy week ahead...a series of storms will
impact the west coast beginning this Sunday and will continue
into late next week. A 994 mb low is progged to move over the Gulf
of Anadyr or Chukotsk Peninsula Sunday morning and will begin an
extended period of long fetch...south to southwest to west winds
over a broad area of the west coast that will continue at
different intensities through at least Saturday of next week. The
first storm is progged to produce 2 to 4 feet storm surge above
normal tides Sunday into Monday along west and south facing coasts
along the Bering Strait and Seward Peninsula. Another storm this
one progged to deepen to around 980 mb will take a similar track
and will likely produce higher water levels as elevated water
levels will persist along the coast from the first storm. The
third and likely the strongest storm in the series is progged to
move into the western bering sea as a 960 mb or deeper low with
several models deepening the low to below 950 mb late Friday Sep
30th and Saturday the 1st of Oct. Winds and water levels are
likely to be highest with the third storm. Considerable model
differences exist on the timing, the track and strength of each
storm, however the general consensus from the suite of models is
that there will be several storms moving across the Bering Sea and
impacting the west coast next week and that a significant storm
is possible toward the end of next week.

Coastal Hazard Potential Days 3 and 4...See Extended Outlook

&&

.HYDROLOGY...Between one half inch and one inch of rain is
expected over the western interior from McGrath northward to
Bettles and northeast to near Prudhoe Bay through Friday evening.
Precip type is expected to be mostly snow above 2000 feet in the
Brooks Range with temperature at or just below freezing. This will
limit runoff in these areas. The rivers over the western interior
where mostly rain is expected will notice rises especially on the
smaller streams and smaller rises on the main stem rivers however
levels are not expected to reach action stage.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning for AKZ205-AKZ206.

Winter Weather Advisory for AKZ218.
&&

CCC SEP 16