textproduct: Fairbanks

KEY MESSAGES

Central and Eastern Interior...

- Warm conditions persist through the weekend, with widespread valley high temperatures reaching into the 70s to mid 80s. Slightly cooler temperatures Friday. Warming again on Saturday and Sunday, with highs reaching the mid 70s to lower 80s.

- Friday brings chances of showers and isolated thunderstorms from Fairbanks north and across higher elevations. Drier weather returns through the weekend.

- Southerly gap winds increase through the Eastern Alaska Range Sunday into Monday as a low pressure system approaches from the southwest. This system ushers in cooler temperatures and more widespread rainfall early next week.

West Coast and Western Interior...

- Warm temperatures continue through the weekend, with inland highs reaching the mid to upper 70s and coastal areas in the 60s to near 70. A Heat Advisory is in effect from noon to 7 PM AKDT Saturday for the Noatak and Lower Kobuk Valleys and Seward Peninsula for temperatures reaching 75 to 80 degrees.

- Dry conditions prevail Friday into Saturday. Isolated thunderstorms are possible in the Kuskokwim Delta area Saturday afternoon. Substantial moisture brings heavy rainfall potential to the southwest coast and inland areas Sunday night into Monday.

- The pattern shifts Monday as a low pressure system moves inland, cooling temperatures through midweek.

North Slope and Brooks Range...

- Warm weather continues across the Brooks Range and Central North Slope through the weekend. Expect highs in the 60s and 70s, approaching 80 near Umiat. Easterly onshore winds keep the Eastern Arctic Coast cooler, with highs in the 50s.

- Shower and thunderstorm activity shifts into the Eastern North Slope and Brooks Range Friday afternoon before drier conditions return Saturday.

SYNOPSIS

An anomalously warm pattern featuring widespread temperatures reaching into the 70s and 80s will dominate Northern Alaska through the weekend as strong upper-level ridging remains entrenched over the state. On Friday, an embedded shortwave will bring cloud cover, a brief temperature dip, and scattered showers with isolated thunderstorms from Fairbanks north through the Brooks Range and Eastern Arctic Slope. Strong high pressure rebuilds overhead on Saturday, returning warmer temperatures and triggering a Heat Advisory for portions of the Seward Peninsula and Noatak/Kobuk Valleys alongside isolated thunderstorms from the Alaska Range into the Kuskokwim Delta. By late Sunday into Monday, an advancing Bering Sea low pressure system will drive gusty gap winds through Alaska Range passes, bringing cooler temperatures and widespread rain to Southwest Alaska.

SHORT TERM /THROUGH SUNDAY NIGHT/

A warm upper-level ridge across Northern Alaska will govern the region's weather through Saturday. On Friday, an embedded shortwave disturbance riding over the ridge axis will push across the North Slope and Eastern Interior, bringing cloud cover, a brief dip in daytime temperatures, and scattered precipitation before high pressure rebuilds overhead on Saturday. By late Sunday, the synoptic pattern begins a sharp transition as a low pressure system advances from the Aleutians toward the Kuskokwim Delta, compressing the pressure gradient over the Alaska Range and nudging the main ridge axis eastward into the Yukon.

Shortwave energy forced southeastward by a weak cold front will trigger scattered showers and isolated thunderstorms Friday afternoon. This activity will be concentrated primarily from Fairbanks northward across elevated terrain, the Brooks Range, and onto the Eastern North Slope. Behind the departing disturbance, high pressure rebuilds over Northern Alaska on Saturday, with elevated 850 mb temperatures of 10-12C supporting widespread highs from the mid 70s to mid 80s across valley locations and the Arctic Plains. A Heat Advisory is in effect from noon to 7 PM AKDT Saturday across the Noatak and Lower Kobuk Valleys and northern and interior Seward Peninsula, where temperatures are expected to reach 75 to 80 degrees. On Saturday, isolated thunderstorms are expected to develop in a band extending from the Alaska Range westward toward the Kuskokwim Delta as a secondary shortwave approaches from the south.

Warm and dry conditions will linger over the Interior and North Slope on Sunday under the remaining influence of the ridge, with minimum relative humidity values dropping to 25 to 35 percent across the Eastern Interior. Meanwhile, as the Bering Sea low approaches the southwest coast Sunday into Sunday night, southerly gap winds will ramp up through Isabel Pass in the Eastern Alaska Range. As moisture spreads into Southwest Alaska, the stage will be set for widespread precipitation early next week.

LONG TERM /MONDAY THROUGH THURSDAY/

The persistent ridge weakens and shifts east into Western Canada early next week as a broad low pressure system advances inland from the Bering Sea into the Kuskokwim Delta. This pattern shift will direct a plume of deep moisture into the state, bringing widespread rainfall potential across Southwest Alaska through midweek. Ahead of the system, strong pressure gradients will drive southerly gap winds through favored passes of the Alaska Range, including Isabel Pass, early Monday morning before winds ease as the low pushes farther inland. As the low meanders across the state through Thursday, unsettled conditions will persist across the region. With high pressure stepping aside, the warmth over Northern Alaska will steadily give way to a cooling trend through the remainder of the forecast period.

Coastal Hazard Potential Days 3 and 4...None

FIRE WEATHER

As upper level ridging continues to build over the state, warm and dry summer-like conditions prevail across much of the state. Embedded within the pattern, a shortwave of energy continues to ride along the periphery of the ridge bringing isolated to scattered showers and thunderstorms to portions of the Central/Eastern Arctic Plains, Brooks Range, and Central/Eastern Interior Friday afternoon. Given the disorganized nature of this shortwave feature, exact thunderstorm locations are a bit uncertain, but will likely bring periods of cooler temperatures and light rainfall accumulations across the region. By Saturday, thunderstorm coverage shifts farther south and west to include most areas south of 65N. Scattered thunderstorms are likely from the Upper Kuskokwim Valley northwest towards the Nulato Hills Saturday afternoon into the evening, with surrounding areas seeing isolated thunderstorms. Thunderstorm activity largely diminishes going into the latter half of the weekend with the exception of a few isolated thunderstorms possible in the Western Brooks Range Sunday afternoon.

Other than thunderstorms, afternoon highs will remain in the mid/ upper 70s across much of Northern Alaska, with most coastal locations seeing temperatures in the mid/upper 60s. By Sunday afternoon, temperatures rise back into the low 80s across the Central/Eastern Interior prompting the potential for a few Heat Advisories to be issued later in the weekend. These warm conditions will yield low min RH values in the 30-40% range across the Interior with the Upper Tanana Valley potentially seeing a few 25-30% values at times over the weekend. Biggest thing we will be monitoring over the next few days will be the chance for southerly gap winds to develop through Isabel Pass Sunday afternoon/evening as a low in the Bering Sea approaches Bristol Bay and tightens the pressure gradient over the Alaska Range. Should this pattern occur, winds may gust upwards of 60 mph at times and present potential fire weather concerns just north of the Alaska Range. However, confidence regarding the strength of these winds remains relatively low for now. Otherwise, winds will remain fairly light and variable across the state going into next week, with much cooler and wetter weather expected Monday into Tuesday.

HYDROLOGY

River levels remain normal. No hydrology concerns are expected.

AFG WATCHES/WARNINGS/ADVISORIES

AK...Heat Advisory from noon to 7 PM AKDT Saturday for AKZ814-816- 818-823. MARINE...None.