High Surf in Alaska, September 18 to 19, 2017

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
224 PM AKDT Sun Sep 17 2017

.DISCUSSION...
High pressure aloft over eastern Alaska and the northern Yukon
Territory will drift east over the next 24 hours as a long wave
trough moves into western Alaska. This trough will continue to
move into mainland alaska through mid-week bringing broad west to
southwest flow to most of northern Alaska. This will result in
periods of precipitation and a cooling trend with more seasonal
temperatures for mid-September. Precipitation will fall as snow
over the higher terrain with snow possible at valley level
primarily in the north and northwest part of the forecast area.
Model solutions begin to diverge some after Tuesday especially
with the placement and track of surface features but the general
consensus is for a cooler and wetter pattern this week.

A weakening weather front currently draped north to south along
the west coast will move east to lie from Deadhorse to Fairbanks
Monday night. Intermittent rain and showers associated with this
feature will progress east to the Alcan border by Tuesday
afternoon. Precipitation will fall as snow at high elevations of
the Brooks range with several inches of snow likely.

Low pressure developing over far east Russia will move to Saint
Lawrence Island on Monday night and then into eastern Norton Sound
on Tuesday. The 18z model run is showing better consistency with
the track of this low, although they are still trying to resolve
the final track into the Interior. This system will spread more
significant precipitation into the west coast from the Seward
Peninsula southward and across the Interior. It will also drag
even cooler air into the state with strong northerly winds along
portions of the west coast by Wednesday.

Coastal Hazard Potential Days 3 and 4...
Low pressure moving west across the Bering Sea and Seward
Peninsula on Tuesday and Wednesday may bring a short period of
high surf to eastern and southern Norton Sound and to the north
coast of the Seward Peninsula. There are some model differences
in the exact track of the low and this is leading to some
uncertainly on the direction and strength of the winds. We will
continue to monitor this situation.

&&

.HYDROLOGY...
Water levels are beginning to fall on the Kobuk River at the
village of Kobuk although minor flooding is still being reported
in the community. The Kobuk River is expected to crest at Kiana
tonight and water levels will gradually fall through the remainder
of the week. On the Koyukuk River, the crest of high water is
moving downriver past Hughes today and to Huslia by Wednesday.
Only bankfull conditions are expected at Hughes and Huslia.
Another weather system moving west to east across the Kobuk and
Koyukuk basins on Tuesday and Wednesday will bring the possibility
of 0.25 to 0.75 inches of rain. There is still some disagreement
in model solutions and precipitation totals. Cooler temperatures
this week will result in snow at higher elevations limiting the
runoff into the Kobuk and Koyukuk Rivers, so additional high water
is not anticipated.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
Small Craft Advisory for PKZ210-PKZ215-PKZ220.
&&

SEP 17