textproduct: Fairbanks

KEY MESSAGES

Central and Eastern Interior... -Sunday will be the last day of widespread highs above 70 in the region. Temperatures cool into the 60 starting Monday as an upper level low moves into the Interior.

-Chances for isolated thunderstorms continue Sunday in the Yukon Flats and in the White Mountains on Monday. More widespread precipitation returns to the region on Monday, with totals up to 0.25 inches expected in the lowlands and up to 0.5 inches over terrain West of Fairbanks between Monday and Tuesday afternoons. Totals in Fairbanks, the Upper Tanana Valley, and the Yukon Flats will be below 0.1 inches.

-Gusty winds pick up in the Alaska Range passes from Sunday morning through Monday night. A Wind Advisory is in effect for the Eastern Alaska Range from 10 AM Sunday through 12 AM Tuesday for gap winds with gusts up to 60 mph in Isabel Pass. Wind gusts will be weaker in Windy Pass, with gusts up to 45 mph expected.

West Coast and Western Interior... -An upper level low will move onshore Sunday into Monday, bringing widespread precipitation to the region. 24-hour precipitation totals will be 1-2 inches in the Kuskokwim Mountains and 0.5 inches in the YK Delta Lowlands and in the Middle Yukon Valley Sunday into Monday.

-Northerly/Northeasterly winds in the Bering Strait increase on Monday, with gusts up to 50 mph possible.

-Temperatures decrease through the period from highs in the upper 50s-mid 60s on the coast and mid/upper 70s inland on Sunday to high temperatures in the upper 50s to low 60s across the region by Tuesday.

North Slope and Brooks Range... -Sunday is the last day of widespread high temperatures in the mid/upper upper 70s in gaps in the Brooks Range and along the Arctic Plains. Temperatures cool throughout to start the week, with highs in the upper 30s/low 40s on the Arctic Coast, and highs in the mid- to-upper 50s inland. A Heat Advisory is in Effect for the Arctic Plains from 1 PM AKDT through 10 PM AKDT on Sunday for temperatures up to 80.

-There is a chance for isolated Thunderstorms in the Brooks Range Sunday afternoon as a shortwave moves across the region.

-An upper level low moves over the Central Brooks Range by Monday afternoon, bringing widespread precipitation to the region. Expect totals up to 1.5 inches in Central and Eastern Brooks Range and up to 0.75 inches along the Northeastern Arctic Plains and Coast.

SYNOPSIS

For the majority of Northern Alaska today could be the final vestige of summer, as a low in the Bering Sea will begin to push out the high pressure that brought us a much warmer weekend. This low will bring widespread rainfall to the Western Interior and West Coast as a front begins to rotate through the region. As this low moves northeast across the Interior it will shift the heaviest precipitation to the Brooks Range and then to the Northeast Arctic Coastline. Temperatures will quickly cool into the 50s/60s across Northern Alaska once the cold front moves through the area. Once, this low pressure moves through the Interior troughing is expected to remain over Northern Alaska keeping us cooler and wetter into this weekend. As we continue to lose daylight, and model guidance is in good agreement that temperatures will remain cool through the end of the month, this could potentially mark our gradual transition into Autumn.

SHORT TERM /THROUGH TUESDAY NIGHT/

The ridge of high pressure that has been present over the past week has shifted east. A weak low has moved onshore over the YK Delta, with a stronger low centered south of the Eastern Aleutians. These two lows will phase with each other Sunday morning and afternoon before the deeper low starts to track to the northeast Sunday night into Monday, bringing precipitation along with it. The heaviest precipitation in the Fairbanks CWA will be in the Kuskokwim Mountains and other areas of terrain in the far southwest corner of the CWA, where up to 2 inches of rain is expected by Monday afternoon. The YK Delta lowlands will see widespread accumulations between 0.5 inches and 1 inch. Chances for isolated thunderstorms over higher terrain in the Northern Interior and Yukon Flats return Sunday afternoon as a series of shortwaves spin off from the lows in the southwest over the interior, especially in areas where little cloud cover develops in the morning and early afternoon hours. Much of the Central and Eastern Interior will remain dry as southerly Chinook flow over the Alaska Range sets up on Sunday into Monday. As is often the case with southerly flow over the range, winds are expected to pick up in the passes Sunday morning through Monday night. The current orientation of the surface low (over Bristol Bay) favors a tighter gradient through Isabel Pass, though strong winds are expected in Windy Pass as well. As a result, a Wind Advisory is in effect for Isabel Pass through midnight on Tuesday for wind gusts up to 60 mph. Windy Pass will see gusts up to about 45 mph. Southerly wind gusts in the Southern Interior may bring smoke from the Tatlanika Fire into Fairbanks on Sunday, but concentrations appear low and elevated according to HRRR smoke. Sunday will be the last day of widespread 70+ degree highs for the foreseeable future in the Interior as ridging is able to cling on in the Central and Eastern Interior.

The low continues on its northeasterly track on Monday, moving into the middle of the state by Monday afternoon. As the low moves to the northeast, so do the areas of highest precipitation. The Nulato Hills and Dalton Highway Summits may see precipitation totals as high as 1.5 inches Monday into Tuesday. More precipitation is also able to make it into the Central and Eastern Interior on Monday now that flow is less southerly, though totals in the region stay below 0.25 inches. The footprint of thunderstorm activity decreases on Monday afternoon, being limited to just the White Mountains, where a lack of cloud cover and precipitation keep temperatures warm enough to support convection when interacting with energy associated with the low. Northerly/northeasterly winds increase up to 35 mph, with gusts up to 50 mph, in the Bering Strait Monday afternoon supported by cold air advection behind the low.

The low continues to weaken and slowly move northeast on Tuesday, with the Central Brooks Range and Northeastern Arctic Plains and Coast seeing the highest precipitation totals, with between 1-1.5 inches expected in the region. This low will help to keep Northern Alaska cooler and wetter through the rest of the week. This will be discussed in depth in the long term section.

LONG TERM /WEDNESDAY THROUGH SATURDAY/

Midweek will be a continuation of what we saw in the earlier half of the work week, as troughing is expected to continue across Northern Alaska. Models are in good agreement that the troughing pattern will continue through the rest of the work week. With this troughing pattern we can expect cooler temperatures, cloud cover, and isolated to scattered showers across Northern Alaska. Very weak ridging could be possible in the Southeastern Interior on Thursday and Friday. There isn't a lot of confidence with this ridging due to the timing of the shortwave troughs moving through the region. If this ridging develops we could see a return of thunderstorm chances to the AlCan Border and Upper Tanana Valley.

Moving into the weekend a low will begin to move southeast from Eastern Siberia and into the Bering Sea. All of the ensembles are in good agreement with this system, as they have system moving into the Bering Friday afternoon. There are some slight differences on the strength and inevitable track, but current guidance keeps it above the 990 mb mark and will keep it south of St. Lawrence Island. With the current track being south of St. Lawrence Island, any coastal impacts from the southwesterly fetch of winds will be minimized.

FIRE WEATHER

Across the West Coast and Western Interior a sweeping cold front from a low in the Bering Sea will bring widespread wetting rains, cooler temperatures, and increased cloud cover. In the Western Interior Valleys we could expect up to an inch of rainfall from Sunday until Tuesday. Areas ahead of the cold front later this afternoon could see some isolated thunderstorm development in the higher terrain from Huslia to Noatak.

As this low begins to move closer to the southwestern portion of the mainland, southerly chinook flow will begin to set up. Southerly gap winds up to 60 mph will be possible through Monday night. These gap winds will help to keep the Tanana Valley warmer and drier. Sunday will be the last above normal day for most of the Central and Eastern Interior with daytime highs in the mid to upper 70s. As the front moves over the Central and Eastern Interior Sunday night wetting rains are possible, but will likely be limited to the higher terrain. In the valleys a T-0.09" of rainfall is more likely.

On the North Slope it will be another warm day across the region with daytime highs in the upper 50s/60s along the coast and mid to upper 70s across the Arctic Plains. We have a heat advisory out for the Central Arctic Plains. We are not anticipating minimum RHs to be a concern as they should remain above 40%.

Moving into Monday as the low is directly over the Interior temperatures will rapidly cool into the 50s/60s across Northern Alaska with the Upper Tanana Valley being the warmest. These cooler temperatures will be the general story for much of the work week as persistent cloud cover and isolated to scattered rain showers keep it cooler.

HYDROLOGY

Expect water levels to rise on rivers throughout the Kuskokwim Delta, Western Interior, and Central Brooks Range as 0.5 to 2.0 inches of rain falls from Sunday night into Tuesday. Rivers are expected to remain within their banks, and no flooding is expected.

AFG WATCHES/WARNINGS/ADVISORIES

AK...Heat Advisory from 1 PM this afternoon to 10 PM AKDT this evening for AKZ806-808. Wind Advisory from 10 AM this morning to midnight AKDT Monday night for AKZ849. MARINE...Small Craft Advisory from 1 AM to 6 AM AKDT Monday for PKZ806- 807-817. Small Craft Advisory from 4 AM to 6 AM AKDT Monday for PKZ816. Small Craft Advisory from 7 PM this evening to 6 AM AKDT Monday for PKZ854.