Brisk Wind Advisory 162, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
148 PM AKDT Sat Apr 20 2019

.DISCUSSION...
An active weather pattern develops over northern Alaska Sunday and
early next week with snow and strong winds developing in the
Western Interior and the West Coast on Sunday and snow developing
over the southern interior Monday and Tuesday.

Aloft at 500 mb, a deep longwave over the Bering Strait south to
the Central Aleutians will rotate to the east to be along a Bering
Strait to Bristol Bay by Monday. A ridge over the southeast
Interior will push north along the Canadian Border Sunday as a
strong shortwave pushes north along the southern Coast. The strong
shortwave will continue to move northwest over Bristol Bay and the
Lower YK Delta Monday afternoon. A second stronger shortwave
pushes onto the southern coast near Yakutat Monday evening and
continues to push north into the southern Interior Tuesday. As the
shortwave moves into the interior strong dynamics aloft will
produce an environment favorable for a mid level as well as a surface
low to develop over the southeast interior by Tuesday morning.

On the surface, a weak low pressure system over Fairbanks will
continue to weaken as it moves to the northwest tonight. Expect
scattered snow showers north and west of Fairbanks tonight and
partly to mostly cloudy skies south and east of Fairbanks. Minimum
relative humidity levels will continue to drop into the 25 to 35
percent range along the upper Tanana Valley and along the northern
foothills of the Eastern Alaska Range. Local winds through the
Eastern Alaska Range passes have increased to the 15 to 25 mph
range with gusts to around 35 mph, however humidity levels in
these areas remain above 30 percent. Very similar conditions are
expected Sunday in the Upper Tanana Valley and through the passes
in the Eastern Alaska Range. Will continue to monitor.

A 982 mb low pushes on shore over the Kenai Peninsula Sunday
morning and continue to push north and west over McGrath as a 984
mb low Sunday evening. Snow develops over the western interior to
the south of Galena Sunday afternoon as the low pushes northwest.
Winds increase over a wide area of the central and western
interior as the low pushes north and west into Western Alaska and
a 1032 mb high pressure system remains in place to the north of
Wrangel Island. Winter Weather Advisories have been issued for
zones 215 and 216 for snow and blowing snow beginning early
Sunday evening and for zones 212 and 214 for snow and blowing snow
for late Sunday evening. Expect 4 to 7 inches of snow and wind
gusts to 40 mph in these areas. Wind gusts to 40 mph are expected
to develop the Sunday evening over the higher terrain and highway
summits in zones 219, the higher terrain and highway summits of
zone 220 as well as the higher terrain and highway summits of zone
221. Wind Advisories for wind gusts to 40 mph have been issued
for these areas.

A 980 mb low develops over the Southeast Interior Monday night as
a strong second shortwave moves over the Southern Interior. Snow
and snow rain mix will expand north and west over much of the
Interior to the east of Galena and to the South of Fort Yukon. At
this time the heaviest snow appears to targeting the Fortymile
Country, the hills north of Fairbanks and Fairbanks as well as a
broad swath from Fairbanks west to near Galena. The precipitation
may mix with rain Monday night and Tuesday morning but should
switch to all snow through the day Tuesday. The low will slowly
drift to the north along the Canadian Border through Wednesday
morning and has the potential to produce heavy wet snow over a
large portion of the Central and Eastern Interior Monday night
into Wednesday. Timing on the switchover from rain to snow as well
as snow levels and the exact storm track will greatly affect
snowfall totals in the interior. Continue to monitor.

The 12z model suite initialized well against the 12 surface
analysis and verified well against the 18z surface analysis. Model
spread remains limited and run to run differences remains minimal.

Coastal Hazard Potential Days 3 and 4...None.

&&

.FIRE WEATHER...
Drier conditions and warmer temperatures expected across the
Interior tomorrow. Minimum RH will range from 20-30 percent south
and east of Fairbanks and 30 to 50 percent north and west of
Fairbanks Sunday. Humidity levels will increase over all of the
Interior as significant precipitation moves into the Interior.

A surface low will move north into the Western Interior Sunday
night. This will cause strong southerly gap winds to develop in
the Alaska Range with gusty southerly winds expected near Delta
Junction The winds will be combined with low RH values near Delta
Junction for a period of time Sunday afternoon. We will need to
monitor this area.

&&

.HYDROLOGY...
Cooler than normal temperatures over the Eastern Interior will
continue through the weekend and into next week slowing the
breakup process; however, extreme caution should be used crossing
any of the Interior rivers as the ice continues to rot and be
eroded from below, and any runoff will be moving into the mainstem
rivers. Caution should also be used on lakes as the ice melts at
different rates.

.AFG WATCHES/WARNINGS/ADVISORIES...
Heavy Freezing Spray Warning for PKZ200-PKZ210.
&&

CCC APR 19