textproduct: Fairbanks

KEY MESSAGES... Central and Eastern Interior

-Gusty winds continue through Monday night. A High Wind Warning is in Effect for Isabel Pass through 12 AM Tuesday for wind gusts up to 70 mph.

-Heavy precipitation is expected to continue in the Central Interior Monday morning through Tuesday morning. Expect 24 hour accumulations of up to 2 inches at higher elevations along the Koyukuk and Dalton Highway Summits, as well as for places like Tanana and Hughes. Rainfall remains lighter (<0.25 inches) from Fairbanks east through Wednesday when post- frontal convective showers extend into the region, especially over higher terrain. Chances for an isolated thunderstorm are possible in the White Mountains Monday afternoon, as well as potentially later in the week.

-Temperatures continue to cool with widespread highs in the upper 50s/low 60s expected in the region (except for the Upper Tanana Valley, which stays in the upper 60s) by Wednesday. High temperatures remain more moderate for the foreseeable future.

West Coast and Western Interior... -Heavy rainfall is expected into Tuesday for higher elevations along the Koyukuk, with accumulations up to 2 inches of rainfall possible between Galena and Huslia by Tuesday morning. This rain could potentially bring sharp rises along the Koyukuk and nearby tributaries. No flooding is anticipated, but smaller creeks and streams could become bankfull.

-Temperatures cool off significantly as a front moves through on Monday evening. Widespread highs will be in the mid 40s/low 50s on the coast and mid 50s/low 60s inland by Wednesday afternoon. Temperatures remain on the cooler side for the rest of the week.

-Northerly wind gusts remain elevated in the Bering Strait on Tuesday, with gusts up to 35 mph possible. Wind gusts diminish on Wednesday to 15 kt.

North Slope and Brooks Range...

-1-2 inches of precipitation is possible along the southern slopes of the Central Brooks Range by late Tuesday. This rain could potentially bring sharp rises along the Koyukuk and nearby tributaries. No flooding is anticipated, but smaller creeks and streams could become bankfull. On the north side of the range, areas in the Eastern Arctic Plains/Coasts could see accumulations between 0.5 inches and 1 inch.

-High temperatures will be in the mid 40s/mid 50s over the plains and in the mid/upper 30s along the coast through most of the week, before increasing to the upper 50s/lower 60s on Thursday.

SYNOPSIS

A broad area of troughing over Northern Alaska continues to produce a wide variety of impacts. For the Central and Western Interior, alongside areas south of the Brooks Range moderate to heavy rain will fall through Tuesday as a front within a broader decaying area of troughing stalls, bringing upwards of 1 to 3 inches of rain before finally dissipating. Meanwhile, strong downsloping winds in the eastern Alaska Range have brought gusty conditions and kept drier weather lingering for locations in the Forty Mile Country. Chances of thunderstorms meanwhile linger across parts of the eastern Interior, including the Yukon Flats. Chances of rain will linger through the week, though showers in the eastern interior will be less widespread and more isolated in nature. Another system arriving late in the week will bring another round of widespread rain and breezy conditions to the west coast and the Bering, before potentially moving inland through the weekend.

SHORT TERM /THROUGH THURSDAY/

An active pattern continues across northern AK through Tuesday, although a short-lived ridge building in on Wednesday will diminish rainfall chances to some extent. Satellite and radar imagery as of the time of writing show a broad area of troughing stretching along a SW to NE axis between St. Paul island and the northern Yukon. The broad area of troughing is bringing with it a wide variety of weather. Moderate to heavy rainfall across parts of the central and western Interior will continue through Tuesday morning, before chances of rain slowly diminish. Atmospheric return Intervals of 5-10 years for some locations will be reflected in precip totals of 2-3 inches for some of these places before the current system winds down. Chances of rain are also present across much of the North Slope and the eastern interior, though rainfall totals for these areas will be substantially lower as more isolated showers and thunderstorms are expected. Along the West Coast, a marine layer will attempt to push back in for some areas overnight into Tuesday, driven by strong northerly flow through the Bering Strait.

CAPE values in the Yukon Flats and parts of the Brooks Range are reaching model progged values of 400 to 600 J/KG through Monday evening. This has fueled the development of isolated thunderstorms, some of which look to have produced breezy conditions, plenty of lightning, and periods of moderate to heavy rainfall.

The last big story has been the wind gusts across the eastern Alaska Range. Chinook winds, driven by the presence of fairly respectable pressure gradient of 5 to 7 mb across the Alaska Range, have resulted in wind gusts as high as 70 mph for Isabel Pass, with other locations seeing wind gusts approaching 60. Winds are currently on a slow downward trend, and look set to continue that diminishing trend through the evening and overnight hours into Tuesday.

Through the day on Tuesday, overall precip coverage and strength will diminish as the trough weakens, though chances of thunderstorms remain across parts of the eastern interior and the Brooks Range. On Wednesday, a ridge briefly begins to build across the interior, which will keep chances of drier weather for the east, even as an old front keeps precip chances for the north slope, and a shortwave brings chances of more widespread rain back in for Southwest Alaska.

LONG TERM /Thursday through Sunday/

On Thursday, weather should lull briefly as weak troughing over Western Alaska will lead to persistent, light showers in the Western Interior. Weak ridging over Canada will lead to warmer and drier, but still moderate, weather in the Central and Eastern Interior as maximum temperatures should remain in the 60s. The North Slope will be cooler than the Interior, but not as wet as Western Alaska.

More impactful weather arrives later in the week as another widespread rain event is expected for the West Coast. The exact timing is uncertain with this system, as deterministic models seem to waver between the bulk of rain arriving overnight Thursday and Friday afternoon. Ensemble models and clustering support the band of rain arriving Friday morning, but it's something we'll want to keep an eye on as the event gets closer. 48-hour rainfall totals for Friday and Saturday along the West Coast currently range between half an inch to an inch. Winds along along the coast will be strong along with the rain. Gusts up to 40 mph through the Bering Strait are possible on the rear side of the system. St Lawrence Island and the YK Delta Coast are also prime candidates for strong wind gusts, but remain slightly weaker for now. After the initial impact in Western Alaska, rain, winds, and cooler temperatures will continue east into the Interior, although to a lesser extent. Southerly gap winds through the Alaska Range are expected to swell Saturday morning before the concensus of models drop the low southeast into the Gulf of Alaska.

Coastal Hazard Potential... No coastal hazards are expected through the week.

FIRE WEATHER

Warm and dry conditions with temperatures well into the 70s and RHs below critical thresholds continue in the southeastern Interior; southerly downsloping winds across the Alaska Range are drying out the air considerably in these areas while also enhancing diurnal warming. A Red Flag Warning has been issued for the Upper Tanana Valley through 7 PM Monday evening for a combination of gusty southerly winds, warm temperatures, and dry conditions. A fire (Mukluk) has already developed in this area in the vicinity of Tok. Through Isabel Pass and into the Delta Junction area, gusty winds, potentially over 50 mph at times, will be possible through around midnight tonight but are not likely to fully drop off until late Tuesday morning. Elsewhere in the Central and Eastern Interior, cooler conditions in the 50s and 60s with RHs above 40% prevail, with isolated thunderstorms occurring and expected to continue near the eastern border through this evening. In Western Alaska and parts of the Central Interior, it is conversely very wet as a low moving inland brings extensive rain and showers with wetting rains to the area. The exception is from near Kotzebue northward, where temperatures are above 70F in spots, although RHs are still over 40%.

By early Tuesday morning, rain (largely wetting) will overspread most of the Middle Tanana Valley (including Fairbanks) and the Yukon Flats, with highs dropping into the low 60s or upper 50s in most areas. The exception will be the Upper Tanana Valley, which will remain mostly dry. Some rain/showers and cooler conditions will also take hold in the Northwestern Interior, ending the streak of warm conditions there the past few days. By the late morning, southerly flow across the Alaska Range will largely end, with moister RHs favored in the Upper Tanana Valley than today. Temperatures are also expected to drop to near or below 70F in these areas, although minimum RHs could still fall into the 30s in some areas. By Tuesday night, while numerous to widespread rainshowers could continue west of Bettles/north of Tanana, they will become sparser and more isolated in coverage elsewhere.

From Wednesday onward, temperatures could recover slightly in the Eastern Interior, with most areas rising back into the mid to upper 60s, with temps around 70 possible in the Upper Tanana Valley, where RHs in the 30s will be possible. Highs in the inland North Slope will briefly fall into the 40s and 50s before recovering into the 60s on Thursday. By the late week, there is a signal for further rain moving into Western Alaska and later the Interior with another coastal low.

HYDROLOGY

Some river rises are expected across the central interior and the Brooks Range, as a stalled front delivers 5-10 year ARIs (2-3 inches of rain) through Tuesday. However, previously low existing stream conditions should prevent any flooding, although a few rivers could reach bankfull. An ESF has been issued which discusses the river rises in additional detail.

AFG WATCHES/WARNINGS/ADVISORIES

AK...Red Flag Warning until 7 PM AKDT this evening for AKZ936. High Wind Warning until midnight AKDT tonight for AKZ849. MARINE...Small Craft Advisory until 6 PM AKDT Tuesday for PKZ806-807. Small Craft Advisory from 4 AM to 10 AM AKDT Tuesday for PKZ808. Small Craft Advisory until 1 AM AKDT Tuesday for PKZ810. Small Craft Advisory until 7 PM AKDT this evening for PKZ811. Small Craft Advisory from 10 PM this evening to 1 AM AKDT Tuesday for PKZ817. Small Craft Advisory from 10 PM this evening to 4 AM AKDT Tuesday for PKZ853. Small Craft Advisory until 10 AM AKDT Tuesday for PKZ854. Small Craft Advisory until 1 PM AKDT Tuesday for PKZ856.