FXAK69 PAFG 161212
Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
312 AM AKST Tue Jan 16 2018
The 00z model run initialized well against the 00z surface
analysis and verified well against the 06z surface analysis. Model
spread remains reasonable in the short range with only miner
differences in timing and position of shortwaves moving northwest
along the back of an upper level ridge centered over the Yukon.
Model spread increases rapidly in both the mid range and the long
range as current weather pattern is showing signs of breaking
down. There remains significant differences in the long range
model guidance however the concensus continues to indicate a
return to more seasonal temperatures over the interior by weeks
end and slightly below normal temperatures early next week.
Aloft at 500 mb, the persistent high pressure ridge over the
Yukon and eastern Alaska will persist through Thursday and then
drift to the north and east. A weak upper level trough and upper
level low will develop over western alaska Thursday and Friday.
South to southeast flow aloft will bring another shortwave north
and northwest over the eastern and central interior this afternoon
and tonight. Forecast soundings continue to indicate a warm layer
aloft with 850 mb temperatures at or just above freezing along
and south and east of a line from from near Fort Yukon to
Fairbanks to near McGrath. Light freezing rain will be possible
through late this evening south and east of this line as
precipitation moves north and northwest through the interior.
North and west of this line light snow is expected with generally
1 to 3 inches expected through Thursday morning over the western
interior as well as the north slope as the shortwave continues to
move north and west.
Winds are expected to increase over the northern foothills of the
Alaska Range and through the Alaska Range passes late tonight and
Wednesday as the shortwave moves north over the Alaska Range,
however winds are expected to remain below advisory levels with
only 40 kts cross barrier flow below 700 mb.
The ongoing warm chinook pattern breaks down over northern Alaska
by weeks end and will usher in a return to more seasonal
temperatures by Saturday and Sunday. Long range models continue to
indicate a much colder air mass entering northern Alaska early
next week, however at this time it is expected that cloud cover
will remain over much of the interior and that the cloud cover
will likely moderate the cold air mass moving over northern Alaska
Coastal Hazard Potential Days 3 and 4...None.
Heavy Freezing Spray Warning for PKZ210.
Small Craft Advisory for PKZ210.
Brisk Wind Advisory for PKZ220-PKZ225.
CCC JAN 18