720
FXAK69 PAFG 042204
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
204 PM AKDT Tue Jun 4 2024

.SYNOPSIS...
The forecast from previous days seems to be on track today and
tomorrow with minimal changes expected. Starting with the West
Coast, winds will be gradually dropping today and tonight and
temperatures become a bit warmer today and tomorrow away from the
Bering Strait coast where snow showers are possible. The North
Slope will be similar with any lingering snow showers dissipating
as it gets warmer today and tomorrow. Isolated showers expected
along the Central and Western Plains/Coast with isolated
thunderstorms expected in the Brooks Range. In the Interior,
showers are gradually developing and will transition to isolated
thunderstorms this afternoon, especially over the higher terrain.
A couple of thunderstorms will be possible in the valleys, and
around the Fairbanks area between 4 to 8 PM this evening. Tomorrow
is looking much more impactful with scattered thunderstorms and
potentially heavy rain.

&&

.DISCUSSION...

Upper Level Analysis...
The models initialized fairly well aloft with a 525 decameter low
over Norton Sound bringing northerly flow over the Bering Strait
and southerly-southeasterly flow over the Western Interior. A 530
decameter upper low will keep southerly flow aloft over the North
Slope today, then turning back on shore tomorrow night as a low
over the Canadian Archipelago moves west over the Beaufort Sea. A
522 decameter low in the Gulf of Alaska which has been persistent
over the last week, will continue to provide easterly to
southeasterly flow in the Interior today and tomorrow with a
couple of shortwaves. Tomorrow in particular will be a strong
shortwave moving through the Interior from the east during peak
heating. Otherwise, this low begins to shift into South- Central
AK later this week with a bit more southerly flow across the
state.

Surface Analysis...
Winds have been relatively strong through the Bering Strait with
gusts 35 to 45 mph from Point Hope through St. Lawrence Island.
There have also been areas of snow in these areas which will
continue through tonight then move west. Otherwise, quieter
weather resumes tomorrow. In the Interior, a 989 mb thermal trough
is stationed just west of Fairbanks and will remain nearly
stationary today, then gradually move west-northwest tomorrow as
it weakens.

Central and Eastern Interior...
A typical summer-like day today with highs in the low to mid 70s
across the Interior, then upper 70s in the Yukon Flats. A Red Flag
Warning is out for the Yukon Flats from 2PM to 9PM this afternoon
with hot, dry and windy conditions. The hot and dry will be there,
but the windy will be a bit more marginal this afternoon.
Otherwise, isolated thunderstorms develop over the Eastern
Interior this afternoon and move west with a chance of storms in
Fairbanks between 4 and 8 PM this evening. Gusty winds looks to be
the main risk with gusts as high as 50 mph. Tomorrow looks to be
much more impactful with a strong shortwave, around 1000+ J/kg of
Mixed Layer CAPE and precipitable water values around 1.0 inch.
This looks to move through around peak heating and would develop a
bit more organized thunderstorms than what we have seen lately.
Some of the strongest storms will have a chance for hail (up to 1
inch in diameter), frequent lightning, gusty winds and heavy rain.
Localized rainfall totals in the most persistent thunderstorms
may be up to 2.0 inches in a short period of time. These storms
will shift northwest and weaken during the evening

West Coast and Western Interior...
Areas of snow expected from the Bering Strait to St. Lawrence
Island today. Accumulations should be minimal as the snow exits
this evening. Northerly winds in these spots may gust as high as
45 mph this afternoon, then those diminish as well this evening.
Otherwise, temperatures will be warmer than they were yesterday
with highs in the 40s and 50s for most coastal locations while low
30s remain along the Bering Strait Coast. Expect isolated
thunderstorms east of Galena today. Temperatures continue to warm
tomorrow with thunderstorms extending farther west from Ambler to
McGrath. A few of these storms may come with small hail, gusty
winds and briefly heavy rain. On Thursday, the shortwave over the
Central Interior moves over the West Coast and Western Interior,
specifically from Galena south and west with areas of rain,
potentially heavy at times. Then by Friday, it looks to dry out
with the exception of a few showers and an isolated storm towards
Ambler.

North Slope and Brooks Range...
Stratus and fog today along the coast with onshore flow
continuing. Isolated showers will be possible along the Central
and Western Arctic Plain this afternoon with isolated
thunderstorms in the Brooks Range. Temperatures will be warming
as well with highs in the 30s and 40s north of the Brooks Range,
and highs in the 60s to near 70 in the Brooks Range. Much of the
same is expected tomorrow as a shortwave moves west in the
Interior. Isolated thunderstorms will be possible in the Central
and Eastern Brooks Range. Friday looks to be quieter, though a
shower or storm is possible in the Western Brooks Range as the
shortwave lifts north. Skies may try to clear along the North
Slope with southerly flow increasing by Friday. Temperatures will
also be warming significantly with highs in the 40s along the
coast.

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

&&

.FIRE WEATHER...
A Red Flag Warning is out for the Yukon Flats for hot, dry and
windy conditions from 2 PM to 9 PM today. The hot and dry will be
met with highs in the upper 70s and min RHs in the low 20s, but
the wind may struggle to hit 15, however it will be close with
gusts to 25 mph. Isolated to widely scattered storms are likely
this afternoon across the Central and Eastern Interior with the
greatest likelihood being in the higher terrain around Fairbanks.

Tomorrow is much more interesting with scattered thunderstorms
developing in the afternoon across the Eastern Interior and
spreading west through the afternoon and evening. These will be
wet thunderstorms and some spots in the most persistent storms may
see 1.0 - 2.0 inches of rain.

Otherwise, no significant fire weather hazards in the short term,
though we will be monitoring the potential for a ridge in the east
this weekend, though confidence is low.

&&

.HYDROLOGY...
Warming temperatures along the North Slope this week will promote
snowmelt and the potential for high water for the Sag, Colville
and Kuparuk Rivers and their tributaries. The Colville has a few
ice jams on it already which may result in some flooding concerns.
One ice jam of note is a known seven mile long ice jam downstream
of Ocean Point (on the Colville) and a smaller ice jam a few
miles long at Horseshoe Bend (roughly 9 river miles up from
Nuiqsut). Snowmelt will likely push out these ice jams, but expect
high water upstream before the release. Water levels are expected
to crest by the end of this week into the weekend.

The water level in Fort Yukon will continue receding very slowly.
Satellites and ground observations continue to indicate abundant
snow in the Porcupine Mountains. As temperatures warm this week,
snowmelt could lead to continued high water along the Porcupine
and the interrelated sloughs.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
AK...Red Flag Warning for AKZ933.
PK...Small Craft Advisory for PKZ801-802-805.
     Gale Warning for PKZ806.
     Gale Warning for PKZ807-857.
     Gale Warning for PKZ810-811-854-856.
     Small Craft Advisory for PKZ812-850.
     Small Craft Advisory for PKZ816-817-851.
     Small Craft Advisory for PKZ853.
     Small Craft Advisory for PKZ858.
&&

$$

Bianco