High Wind in Alaska, October 2 to 3, 2017

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
210 PM AKDT Sun Oct 1 2017

.DISCUSSION...
The 12z models suite initialized well against the 12 surface
analysis and verified well against the 18z surface analysis. Model
spread remains reasonable in the short range but increases
considerably in both the mid range and the long range.

Aloft at 500 hpa, an upper level ridge with axis from near Point
Hope south and eastward to near Yakutat and then into the eastern
Gulf of Alaska will continue to build north and will rotate to the
east and will be centered along a Demarcation Point to Yakutat
line Monday morning. The ridge will continue to retreat to the
east as as strong shortwave moves north along the west coast of
alaska. An upper level low moves southeast into the northwest Gulf
of Alaska and imparts a negative tilt to the long wave trough over
the central Bering Sea and will contribute to an environment
favorable for rapid surface cyclogenisis over the central Bering
Sea Tuesday and Wednesday of this week.

The ridge building overhead over central Alaska will contribute to
mild weather for early October. A strong shortwave rotates north
along the back side of the ridge and will be along the southern
coast this evening and over the Alaska Range late tonight and over
southwest Alaska Monday. Strong south to north cross barrier flow
aloft develops tonight over the Alaska Range. A mountain wave
develops along the Alaska Range and will contribute to forcing
strong winds aloft to the surface through the northern foothills
of the Alaska Range where high wind warnings have been issued for
wind gusts to around 70 mph devloping after midnight and
continuing through the day Monday. Mostly cloudy skies with only a
slight chance of rain is expected over the southern interior to
the east of Manely Hot Springs with abundant drying down slope
winds. To the west of Manely Hot Springs a chance of rain is
expected in the western interior and rain is likely over the YK
Delta on Monday.

On the north slope the arctic front has moved north of the coast
bringing an end to the freezing rain and freezing drizzle that
occurred this morning and early afternoon as the arctic front was
overridden by a warm and moist southwest airmass moving north
east out of the Bering Sea. Long fetch southwest winds will
continue to move through the Bering Strait and will bring elevated
surf as well as high runup along the coast from Kivalina north to
Point Hope as well as along the northwest coast near Barrow this
evening. Surf levels will drop tonight as winds diminish. A high
surf advisory continues through 10 PM tonight for the coast north
of Kivalina to Point Hope.

Strong winds are expected to develop tonight through the Alaska
Range passes as well as the northern foothills of the Alaska
Range. A strong mountain wave will develop along the lee of the
Alaska Range and will promote strong winds aloft to be forced to
the surface. Wind gusts around 70 mph are expected to develop
late this evening and continue through the day Monday.

Coastal Hazard Potential Days 3 and 4...None.
Models continue to struggle with the position, track and strength
of a low pressure system progged to develop in an environment favorable
for rapid cyclogenisis over the central Bering Sea Tuesday and
Wednesday. At this point model concensus between the ECMWF and the
Canadian model would bring the low on a track far enough south
where the most significant coastal impacts would be south of
Hooper Bay however the GFS with a more northerly track would bring
storm surge and high winds into to the YK Delta coast late
Wednesday and Thursday. Continue to monitor.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
Wind Advisory for AKZ223.

High Surf Advisory for AKZ207.

High Wind Warning for AKZ225-AKZ226.

Small Craft Advisory for PKZ220-PKZ225-PKZ230-PKZ240-PKZ245.
&&

CCC OCT 17