189
FXAK69 PAFG 262101
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
101 PM AKDT Fri Jul 26 2024

.SYNOPSIS...
Is summer over? Not technically, but it will feel like it as a
cold front sweeps east, bringing rain and cooler weather to the
remainder of the Mainland this weekend. Snow will also fall to the
surface over parts of the Arctic Coast and N Slope this weekend.

&&

.DISCUSSION...

Upper Levels and Analysis...
There is a 547 dam low over Southwest Alaska with a departing
upper level ridge, now over the Yukon and NW Territory, with
heights around 572 dam. A cold front is tracking east, with that
front currently over the Central Interior. There is another
separate cold front over the Arctic, with moderate rainfall
extending W-E along that front. A thermal low persists over the E
Brooks Range.

Model and Forecast Discussion...
The models are fairly well clustered over the next few days, but
there are some uncertainties regarding the strength of a
wraparound band of rainfall on Saturday arcing from the Central
Brooks Range down to the S Interior around Fairbanks. The ECMWF
and Canadian models are notably stronger with that feature, with
heavier rainfall extending all the way down to Fairbanks. Given
the current strength of this low, this seems reasonable, so this
forecast will trend wetter. Also, it looks fairly reasonable that
the same feature will cause sufficient height falls/surface
pressure falls for a switch to all snow over parts of the N Slope
and Arctic coast Sat and Sat night, which we will also trend
towards.

Central and Eastern Interior...
Rainfall will shift east tonight along a cold front, with
southwest winds behind this front bringing in much cooler air
with it. There will be some breaks in rainfall early Saturday,
then it will fill back in as showers in the afternoon over most of
the Interior, with showers continuing into Sunday morning. It will
be briefly drying out Sunday evening with more rainfall moving in
Monday. Saturday looks like a fairly "raw" day with blustery
southwest winds to go along with the afternoon showers and temps
struggling out of the 50s. Isolated thunderstorms will be possible
through this weekend right along the ALCAN border, but right now,
it looks pretty meagre.

West Coast and Western Interior...
Rain and showers will wrap around a departing low, favoring the
Yukon Valley and the Norton Sound region, as well as the Upper
Kobuk and Noatak Valleys, through Saturday. High elevation snow
above a couple thousand feet in the Brooks Range can also be
expected as colder air wraps around the low center. It will be
briefly drying out Saturday night and Sunday as the low shifts
east, but more rainfall shifts inland Sunday night and early
Monday, along with near gale force north winds down the Bering
Strait Sunday night and Monday.

North Slope and Brooks Range...
Rainfall will be turning into accumulating snowfall for parts of
the Arctic Coast and N Slope this weekend, with the best chance
for snowfall from Prudhoe Bay to Toolik Field Station to the
Central Brooks Range. Several inches of snowfall is likely over
the higher passes, with a skiff to 2 inches for lower elevations
near the coast. Moderate to heavy rainfall of 1-2 inches is
likely, as well, before the turnover to mixed snowfall later on
Saturday. Snow and rain is tapering off Sunday night, with high
pressure persisting along with northeast winds.

Extended Forecast Days 4-7...
Broad upper level troughing will be in place Monday night and
Tuesday with cooler temps and showers persisting into Wednesday.
The latter half of the week will see more wet weather moving into
the West Coast as Bering fronts shift inland, which will keep
temps running slightly below seasonal norms.

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

&&

.FIRE WEATHER...
A cold front sweeping east will shift all warm air into Canada
with wetting rains moving across the final dry spots of the
Interior, the Yukon Flats and SE Interior, this evening and
tonight. Showers and rainfall will persist through the weekend
along with temps below seasonal norms. The only slight chance for
thunderstorms will be along the ALCAN this weekend, with no
thunderstorms forecast early next week. Expect general southwest
winds and blustery conditions for Saturday.

&&

.HYDROLOGY...
1-2 inches of rainfall is expected over the Central Brooks Range
through this weekend, which will push some rivers draining into
the arctic to near action-stage this weekend, including the Sag
River. All rivers draining the Brooks Range will see rapid rises,
however, including the Koyukuk and Alatna.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...None.
PK...Small Craft Advisory for PKZ806.
     Small Craft Advisory for PKZ807.
     Small Craft Advisory for PKZ810.
     Small Craft Advisory for PKZ811-857.
     Small Craft Advisory for PKZ812-858.
     Small Craft Advisory for PKZ813.
     Small Craft Advisory for PKZ814-815.
     Small Craft Advisory for PKZ854.
     Small Craft Advisory for PKZ856.
     Brisk Wind Advisory for PKZ859.
     Brisk Wind Advisory for PKZ860.
     Small Craft Advisory for PKZ861.
&&

$$

Ahsenmacher