035
FXAK69 PAFG 232200
AFDAFG
Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
200 PM AKDT Tue Jul 23 2024
.SYNOPSIS... Heat is here as temps are well above seasonal normals
this afternoon, with hot temps into the mid to upper 80s for most
of the Interior. Heat continues Wednesday, with slightly cooler
temperatures on Thursday along with increasing thunderstorm
chances. It gets much cooler Friday as a front from the Bering
moves inland, bringing increased chances of rainfall.
&&
.DISCUSSION...
Upper Levels and Analysis...
No change in the upper air pattern for the last several days, with
ridging over the W Mainland, with heights around 579 dam. There is
a massive arctic low spanning the whole arctic region from the
North Pole down to the Arctic coast, with the center of that low
around 522 dam. There is a stationary cutoff low over the W Bering
Sea with heights around 546 dam. There is a 557 dam Gulf of AK
low, with a shortwave trough moving west across the Copper Basin
of AK, south of the E Alaska Range. There is another shortwave
trough shifting from the E Arctic to the NE Interior. A "backdoor"
cool front is moving across the E Brooks Range into the N Yukon
Flats this afternoon, bringing northeast winds.
Model and Forecast Discussion...
The numerical weather models are well clustered, but continue to
shift back and forth with the potential for shortwave energy to
cross the Alaska Range on Wednesday afternoon, sparking some
stronger thunderstorms over higher terrain. In addition, they
continue to slow down with the main front moving in from the
Bering Sea, which is not a surprise given the strong ridging
aloft. We will continue to highlight hot temps through Wednesday,
and warm temps through Thursday, along with increasing
thunderstorm chances by Wednesday evening and through Thursday.
The big cooldown begins Friday as the Bering front shifts inland
with rain and showers. Favored model is the NAM nest for winds and
NAM/GFS/ECMWF blend for everything else, with NBM for high temps
and minimum relative humidity.
Central and Eastern Interior...
Hot this afternoon with temps in the mid to upper 80s, with some
local 90 degree hot spots. Temps will be near record levels this
afternoon and again on Wednesday across the area. Northeast winds
will be in place through the Yukon Flats with light north winds
over the remainder of the Interior, except slightly breezier winds
in the Alaska Range passes with gusts to 20 mph. Very isolated
thunderstorm chances are possible over the higher elevation
terrain west of Fairbanks this afternoon, and up towards the
Dalton Highway and over the S Slopes of the Brooks Range. But they
will be very few and far between, and it will mostly just be hot
and dry.
Wednesday starts out dry and hot, but there will be a better
chance for afternoon and evening thunderstorms over the Alaska
Range and parts of the S Interior as weak upper level energy
crosses the Alaska Range and induces south winds aloft. Some
storms may go into Wednesday night over the southern half of the
Interior.
Thursday will still be warm, but there will be more clouds and a
better chance for afternoon thunderstorms, especially over the
Central Interior where there will be a better focus along the cool
front.
West Coast and Western Interior...
Another scorcher this afternoon over the Interior with warm temps
region wide, except over the NW Arctic where some onshore winds
and stratus may stick around at times. An isolated thunderstorm is
possible late this afternoon from the Yukon Valley eastward,
mainly over higher terrain features. More heat on Wednesday with a
better chance for late afternoon and evening thunderstorms over
the Lower Yukon Valley to the Delta and east to the Kusko Valley.
Some storms drift north overnight. Thursday is cooling with
widespread showers and thunderstorms across the region as a cool
front shifts east from the Bering to the Interior. Friday is much
cooler and much wetter as the main low shifts inland.
North Slope and Brooks Range...
Drying and warming with southwest winds beginning later this
afternoon. This general pattern then persists through Thursday.
Thursday night, thunderstorms and showers move across the Brooks
Range and lift north into Friday as a low pressure system shifts
across the region.
Extended Forecast Days 4-7...
A Bering low is shifting inland and moving the ridge off to the
east as much cooler and wetter weather moves in for the next
several days, beginning Friday. The entire suite of numerical
models and the ensembles, from GFS to ECMWF, as well as the EC AI
model, are all showing deep troughing over the Mainland, with
below normal temps into the beginning of August. Is summer over?
Perhaps not, but the hot temps of this summer likely are.
Coastal Hazard Potential Days 3 and 4...None.
.FIRE WEATHER...
Hot this afternoon and Wednesday with only isolated wet
thunderstorm chances this afternoon over Interior highlands.
Highs in the mid to upper 80s to around 90 the next two days with
min RH levels around the low 20 % range in the hot spots.
Northeast winds over the Yukon Flats will be 5 to 10 mph in the
afternoon. North winds in the AK Range increase again this
afternoon to 10 to 15 mph. Widely scattered wet thunderstorms are
possible late Wednesday afternoon over the Alaska Range and S
Interior, mainly over SW AK. Widely scattered wet thunderstorms
increase in coverage Thursday as temps cool slowly as a front
makes inland eastward progression. South winds in the AK Range
increase Thursday.
.HYDROLOGY...
No concerns.
&&
.AFG WATCHES/WARNINGS/ADVISORIES...
AK...None.
PK...Small Craft Advisory for PKZ811-857.
Small Craft Advisory for PKZ812.
Small Craft Advisory for PKZ813.
Small Craft Advisory for PKZ815.
Small Craft Advisory for PKZ858.
Brisk Wind Advisory for PKZ859.
Brisk Wind Advisory for PKZ860.
Small Craft Advisory for PKZ861.
&&
$$
GJM