textproduct: Fairbanks

PREV DISCUSSION

/issued 354 PM AKDT Wed Jun 17 2026/

SYNOPSIS... A warming trend begins today across most of Northern Alaska with showers and thunderstorms becoming more prevalent each day through Saturday. Temperatures will rise in the Interior through the week with highs in the 70s to low 80s likely in most Interior Valleys by Friday. The hottest locations will be in the Yukon Flats and Eastern Interior as some spots reach the mid to upper 80s. The West Coast remains seasonably cool, in the 50s and low 60s while the North Slope is warm with highs in the 50s to 70s from north to south, and 60s/70s in the Brooks Range through Saturday. Back to the thunderstorms, they will develop not only in the Interior, but also the Brooks Range, North Slope and Seward Peninsula today through the weekend. Given that it is a busy weekend for activities in Northern Alaska, keep and eye to the sky and be weather aware as a few of these thunderstorms may be strong.

KEY WEATHER MESSAGES... Central and Eastern Interior... - A warming trend beginning today with highs a couple of degrees above normal. Expect highs in the upper 70s and low 80s in the Central Interior by Friday with mid to upper 80s expected in the Yukon Flats and portions of the Eastern Interior this weekend.

- Showers and thunderstorms develop and become more prevalent throughout the week and into the weekend.

- Highest probability for thunderstorms in the Interior is Friday and Saturday.

West Coast and Western Interior... - Temperatures remain seasonably cool along the Coast with highs in the 50s to low 60s through the weekend. A warming trend in the Interior with highs in 60s to near 70 today, then mid to upper 70s by the weekend.

- Showers and thunderstorms will be prevalent today and tomorrow then gradually move east by the weekend. Today will be isolated over the seward Peninsula and in the Western Interior, while Thursday shifts to mostly the Interior and become a bit more numerous.

- Thunderstorms persist on Friday in the Western Interior, mostly from McGrath to Huslia east. A farther east progression persists on Saturday with most storms south and east of Ruby.

North Slope and Brooks Range.. - A warming trend begins today, expect high temperatures to increase through Friday, getting up to the 50s, even near 60 for portions of the coast, 60s to mid 70s in the Plains and 70s to near 80 for the valleys of the Brooks Range.

- A cold front arrives on Saturday afternoon with cooling temperatures and chances for rain from west to east through Sunday.

- Thunderstorms will be around the Brooks Range and Arctic Plain each day through the weekend with the most abundant coverage being Saturday and Sunday afternoons.

FORECAST ANALYSIS AND DISCUSSION... The warming pattern is taking shape as ridging builds in from the southwest and northeast. A low over the Gulf of Alaska will move east into SE AK then away from the state by Friday. While this is happening, a low over the Chukchi Sea will drop south and phase with energy moving over the Bering on Thursday allowing for a a fairly weak upper low to close off at about 561 decameters. This low will remain nearly stationary through Saturday then drop south to the Eastern Aleutians Saturday night into Sunday. The importance of this low is it keeps the West Coast and Western Interior cooler than the rest of Northern Alaska while also providing ample lift for convective development later this week in the Western Interior.

Over the remainder of Northern Alaska, ridging aloft will allow for an influx of much warmer 850mb temps. Currently they are around 5 to 10C with the warmest being in the SE Interior and the coolest on the North Slope. By Friday, they will be between 7 and 12C from north to south, excluding the West Coast which remains cooler. Once we get 10-12C 850mb temps, surface temps can approach 80F. We continue to see an increase in the Interior on Saturday, between 10-14C. This can allow for surface temps in the low to mid 80s, potentially upper 80s in the Yukon Flats. Up north there will be a cold front moving through allowing for cooler temps to arrive from west to east. This front looked a bit more amped yesterday, but today is weaker and remaining farther north. Therefore, it looks to remain warm for quite a while from the Brooks Range southward, but chilly north of there into next week.

With warm weather comes thunderstorms and other than some isolated storms today and tomorrow, Friday and especially Saturday look particularly impactful. There are a lot of activities going on around the state and we are expecting an abundance of thunderstorms which may have frequent lightning and other typical thunderstorm attributes. There is a bit of uncertainty with the placement of the upper level ridge, but numerous shortwaves will pivot around the ridge into the Interior, allowing for thunderstorms to continuously develop. Friday and especially Saturday night, thunderstorms have the chance to continue due to the strong forcing aloft. This active thunderstorm trend with warm weather looks like it may persist well into next week.

FIRE WEATHER... Active thunderstorm days are expected towards the end of the week and into the weekend. The most prevalent days in the Western Interior will be Wednesday and Thursday afternoons, though these storms will be isolated in nature. The Central/Eastern Interior will see isolated storms on Wednesday and Thursday, then scattered thunderstorms Friday and Saturday afternoons. We may see isolated thunderstorms continue throughout Friday and Saturday nights as the atmosphere remains unstable, but confidence remains low for now. We do however have high confidence in temperatures warming up across the Central/Eastern Interior with highs in the low to mid 70s today, mid to upper 70s on Thursday, then widespread upper 70s to low 80s from Friday through Sunday. The Western Interior remains slightly cooler with highs in the low to mid 70s through Friday, then potentially some upper 70s this weekend. We will be monitoring how the ridge develops and moves across the Interior. RHs will dry out, especially in the Yukon Flats and Tanana Valley from Thursday through the weekend with minimums in the teens and low 20s expected. Elsewhere, RHs in the mid 20s to mid 30s seem reasonable with higher values across the Western Interior. Winds remain fairly light through the weekend, outside of some gusty outflow winds.

HYDROLOGY... Most of the concern from the recent heavy rain in the Brooks Range has diminished. We'll notice some higher water in Allakaket tomorrow as well as on the Colville River. But observed values have been near bankfull. We still have a Flood Advisory for the Colville River and Umiat will be seeing cresting water over the next 36 hours. This water will continue to move downriver towards Nuiqsut with minor flooding of low-lying areas possible.

EXTENDED FORECAST DAYS 4-7...Saturday night through Tuesday night. The extended forecast period begins with a seasonably weak closed low over the Alaskan Peninsula and an unseasonably deep Arctic low centered near the North Pole. Except for weak troughing extending south across the North Slope this weekend, a ridge axis extending west from Canada dominates weather across interior Alaska. A weak front focuses shower and thunderstorm potential along and east of the boundary through the middle of next week. There is good model agreement that this frontal boundary will be oriented roughly between McGrath and Bettles Saturday afternoon before shifting to be more west-east oriented from McGrath to Eagle by Monday afternoon. The summer solstice provides plenty of insolation to fuel thunderstorm activity so frequent lightning and gusty winds are expected with the strongest storms, despite rather weak synoptic scale forcing. Some guidance suggests a more robust easterly wave by the middle of next week, but confidence in that feature is low at this time.

Coastal Hazard Potential Days 3 and 4...None

AFG WATCHES/WARNINGS/ADVISORIES

AK...None. PK...None.