761
FXAK69 PAFG 201038
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
238 AM AKDT Mon May 20 2024

.SYNOPSIS...
Fairly benign weather continues for most of the Mainland. Moderate
rain showers continue over the SE Interior and E Alaska Range with
a continued run of temps above seasonal norms for the Interior,
which will continue for the next couple days before moderating
cooler. A front will bring more rain to the West Coast tonight and
Tuesday. Break-up continues along the Yukon River with the break-
up front now moving toward the Delta as it passes through Pilot
Station. The Sag River is now beginning to show signs of breaking
up, and it will need to be watched for the future.

&&

.DISCUSSION...

Upper Levels and Analysis...
There is a 537 dam mobile low over the NE Gulf of AK which is
bringing dousing rain showers to parts of the E Alaska Range and
SE Interior (mixed higher elevation snows). There is a weak ridge
aloft over the Interior with a double-barreled 531 dam upper low
over the Bering Sea. There is a 1030 mb arctic high over the high
arctic, with a 991 mb low over the Central Bering Sea. There is a
1009 mb low over the SE Interior.

Model Discussion...
Models are locked into the pattern for the next several days.
THere are some minor discrepancy with how they handle the
development of a secondary low over the Gulf of AK midweek, which
will influence the chances for Interior rainfall late Wed and Thu.
For now we will favor a ECMWF/GFS blend which is more bullish on
developing a triple point low in the Gulf and bringing rain
chances inland. For winds, we will favor the hi res models.

Central and Eastern Interior...
Showers over the Upper Tanana Basin and E Alaska Range taper off
today then end tonight. There will be a few showers over the
Interior today, but it will largely be dry otherwise with partly
clearing skies and another warmer than average day. Tuesday starts
out sunny than a fast moving front will bring clouds over the
Interior in the afternoon, with chinook flow over the AK Range
causing warming and strong south winds to near 50 mph through the
passes. Chinook flow gradually wanes Wed night and that will
increase chances for rain and showers into Thursday for parts of
the Interior, although confidence is low at this time.

West Coast and Western Interior...
Fairly dry today with increasing southeast winds ahead of a front
which will bring widespread light rainfall along a front which
will move from the YK Delta northward through Tue night. Behind
this front, showers and cooler weather will persist through Wed
with a gradual drying trend through Thu. Expect around a half inch
of rainfall over the YK Delta and Lower Yukon with slightly lower
amounts further northward.

North Slope and Brooks Range...
Stratus, fog, periodic snow showers and east winds will dominate
for the next several days. Wind gusts to gale force will develop over
the W Arctic from Point Lay to Point Hope Tuesday into early
Wednesday. There is a chance that snow showers may turn to mixed
precip after Tuesday as warmer air aloft moves in, with spotty ice
pellets or possibly freezing drizzle.

Extended Forecast Days 4-7...
The extended period beginning Thursday is fairly messy among the
global models, but the general signal is there will be another
Bering low moving across Bristol Bay into the Gulf of AK. The
degree of northward progress of the front into SW AK is less
certain, with some models more aggressive in bringing more
rainfall to SW Alaska. Either way, the low dives into the Gulf and
it will be fairly showery over the Interior and will eventually
dry out over the West Coast. No significant temp or precip
anomalies are noted in the extended through next weekend.

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

&&

.FIRE WEATHER...
Min RH values are again in the upper teens to lower 20 percent
range for the Interior with the exception being the SE corner and
E Alaska Range where it will be cloudier with showers. No thunder
is anticipated the next few days with stable flow over the
Mainland. Tuesday, a front moves to the AK Range with a low end
chinook, which will push the gap winds to 35+ mph, and to near 30
mph for Delta Junction. Min RH values will be around 25 percent,
so it will be near critical fire weather conditions in that area.
Wetting rains will move across the Delta and W Interior with that
same front on Tue.

&&

.HYDROLOGY...
The ice jam on the Lower Yukon at Pilot Station has released and
water levels are slowly falling at the river gage at Pilot Station
this morning. The latest reports from Mtn Village were ice was
flowing and moving downriver, with water levels rising slightly.
The break-up is expected to reach Alakanuk and Emmonak sometime
late Tue into Thu based on current trends and satellite imagery,
which is showing some open water and decaying ice. Residents near
Mtn Village and Saint Mary`s should keep an eye on water levels
as they are expected to continue rising. Future flood products may
be needed.

There are no new reports about the Buckland River, but there was a
reported ice jam downstream of Buckland a couple days ago with
rising water levels. We will continue to monitor.

The water levels along the Porcupine River at Old Crow have risen
due to snowmelt along with additional ice runs as breakup
continues. Water levels are projected to be high along the
Porcupine until snowpack in the basin is depleted, which will
continue to remain high into next week.

The Sag River is beginning to open up along the N Slope, as
webcams are showing water over ice with open waters toward the
upper portions of the river.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...

AK...Flood Watch for AKZ826.
PK...Small Craft Advisory for PKZ801.
     Small Craft Advisory for PKZ811.
     Small Craft Advisory for PKZ812.
     Small Craft Advisory for PKZ816-851.
     Small Craft Advisory for PKZ850.
     Brisk Wind Advisory for PKZ853.
     Brisk Wind Advisory for PKZ857.
     Brisk Wind Advisory for PKZ858.
&&

$$

Ahsenmacher