textproduct: Fairbanks

SYNOPSIS

Spring-time is here for areas south of the Brooks Range as the snow continues to melt, river breakup progresses further downstream, and temperatures remain steadily in the 50s and 60s through the weekend. The North Slope, however, is expected to continue to see temperatures in the upper 20s and lower 30s. As a low approaches from the Bering Sea, it will bring robust moisture resulting in scattered precipitation for the West Coast and Western Interior this weekend and isolated showers for the Interior. Gusty southerly winds are expected to pick up today through the Alaska Range passes and are expected to persist through the weekend.

KEY WEATHER MESSAGES

Central and Eastern Interior...

- Warming conditions expected through this weekend with highs in the upper 50s to lower 60s with southerly flow over the Alaska Range and clearer skies possible.

- Gusty winds are possible for the Alaska Range passes beginning Saturday morning and last through the weekend. Wind gusts as high as 60 mph are possible, especially Sunday morning.

- Isolated showers associated with shortwave energy will be moving northward near the Al-Can border. There is a slight, nonzero percent chance that this energy may produce an isolated thunderstorm for the southeastern Interior near Eagle.

- Areas north of the Alaska Range are currently quite dry. Any showers that will occur within the next few days are likely to be isolated due to drier air in the lower levels.

West Coast and Western Interior...

- Warming temperatures are expected the next few days, with highs rising into the 50s across the Western Interior and Seward Peninsula and 40s across the YK Delta.

- Generally dry conditions are expected for the next few days with only scattered showers possible for portions of the YK Delta and Seward Peninsula. Chances for precipitation will be more likely on Saturday for the YK Delta.

North Slope and Brooks Range..

- High temperatures on the North Slope will range from the mid 20s to the lower 30s through the weekend, potentially reaching around 40 in the Southwestern Brooks Range.

- Mainly dry conditions expected to prevail across the region for the next several days.

FORECAST ANALYSIS AND DISCUSSION

A weak, upper-level low will continue to move northwestward over the Yukon Flats and towards the western Brooks Range today, bringing minimal impacts to the Interior besides the possibility of an isolated shower. This energy will continue to travel northwestward and eventually combine with the trough in the Bering Sea. South of this low is an area of weak shortwave energy that will be associated with isolated showers and a very slight chance of thunderstorms, specifically in the southeast Interior near Eagle.

A Bering Sea low will approach the YK Delta, but not quite make landfall. This low will draw additional moisture northward, bringing scattered showers for the YK Delta and Seward Peninsula beginning this weekend. There is a very slight, nonzero percent chance of a thunderstorm with these showers. Accompanying these showers will be gusty easterly/southerly winds for the YK Delta and Western Interior. These winds will generally be strongest in the afternoon and evenings and stronger around thunderstorms if they form. Areas north of the Alaska Range currently have a large dewpoint depression, meaning any showers that fall will have to rise the dew point, likely resulting in the showers being isolated.

Due to this low remaining in the Bering Sea throughout the weekend and a Northeastern Arctic High, a pressure gradient will form over the state, especially over the Alaska Range. Upwards of 6 mb of a pressure gradient and southerly flow through the Alaska Range will create gusty winds this weekend, beginning Saturday morning with the strongest wind gusts as high as 60 mph possible Sunday morning in Isabel Pass and 50 mph in Delta Junction. Wind Advisories have been issued for both areas. As a result of these strong winds and dry conditions, a Red Flag Warning has been issued for Delta Junction throughout this weekend.

FIRE WEATHER

Broad upper level troughing over Western Alaska coupled with a ridge of high pressure centered over the NE Pacific into NW Canada will continue to support southerly flow into Northern Alaska, aiding in keeping warm and mostly dry conditions around this weekend. A series of shortwaves working around a low in the Bering Sea will be the main driver of moisture transport into the Interior this weekend, as a weaker upper level low continues to traverse northwest through the Interior towards the North Slope, gradually being incorporated into the Bering Sea low. As that low in the Bering shifts NE this weekend, this will help to develop a stronger pressure gradient with high pressure in Canada and allow for winds to shift from a more northerly component to carrying a southerly and easterly direction this weekend. Precipitation chances with this system will remain isolated aside from the Yukon Delta where more scattered chances are expected, leaving Northern Alaska mostly dry heading into early next week aside from some isolated showers at times.

The largest impact from this setup will be strong winds through the Alaska Range passes, particularly Isabel Pass and up towards Delta Junction. A Red Flag Warning has been issued for Delta Junction for Saturday and Sunday for wind gusts up to 50 mph and RHs in the low 20s. Winds will strengthen slightly in the rest of the Interior, predominantly easterly with strongest gusts in the evening. Temperatures will rise into in the mid 60s for most spots in the Interior and we may even see reach towards 70 in the Yukon Flats down to Eagle on Sunday. Minimum relative humidities are expected to be in the 20-30% range each afternoon this weekend, with localized teens in Interior Valleys and the Yukon Flats. Conditions will fair slightly better in the Western Interior where moisture advection is higher and chances for showers are more likely. Thunderstorms are not expected this weekend, except along the AlCan border in the higher terrain around Fortymile Country on Saturday.

Looking into the extended, models are showing increased confidence on another low pressure system working through the Aleutians into the Bering Sea for Thursday and Friday as the initial low in the Bering Sea this weekend into early next week gradually weakens and dissipates. This will continue to reinforce and support daily isolated to scattered precipitation chances across Northern Alaska in addition to increased winds through Alaska Range Passes and at Delta Junction through Tuesday night and again picking up on Thursday. Precipitation amounts overall through the extended forecast continue to look light. Given the time of year with temperatures across much of our region south of the Brooks Range seeing highs hold steady well into the 50s and 60s, daily isolated thunderstorms will also be possible that will peak in coverage each afternoon and evening.

HYDROLOGY

Yukon River: The ice jam at the Yuki river, which had remained in place for nearly two and a half days, finally released Thursday afternoon sending a strong surge of ice and water downstream toward Galena. The release triggered rapid downstream breakup with rapidly changing conditions along the river. The initial surge carried large intact sheets through Bishop Rock, which has reduced the threat of an ice jam forming there. Late Thursday evening the main ice run was seen moving steadily past Galena.

At Koyukuk, ice was moving steadily past the community while water levels continued to rise and back up the Koyukuk River, however no significant flood has been reported as of this morning.

Water levels are expected to continue rising in both Galena and Koyukuk as large volumes of water previously locked up behind the ice jam continues to move downstream. The River Watch team reports that water levels behind the previous jam are comparable to the 2023 breakup season. Thus it is expected that minor flooding will remain possible in Galena and Koyukuk in the coming days. Thus flood watches will remain in effect for these areas.

Further upstream, high water continues to move downstream from Stevens Village through Tanana.

Chena River: The Chena River continues to respond to warmer temperatures with higher elevation snowmelt leading to rivers running higher than normal, but likely remaining below action stage.

Additional Information: Visit www.weather.gov/aprfc for the latest hydro information.

Please report observed flooding to local emergency services, law enforcement, or to the National Weather Service when you can do so safely.

EXTENDED FORECAST DAYS 4-7

Tuesday through next Friday. With a persistent upper level low situated in the Bering Sea midweek next week, southerly flow will continue across Northern Alaska which will keep temperatures mild and daily precipitation chances going. A broad ridge of high pressure centered in the NE Pacific will continue to support to support a broad troughing pattern in the Bering Sea. A series of shortwave troughs propagating around the main low center mid to late week will aid in this moisture transport from the West Coast and Yukon Delta into the Interior and Brooks Range, all while the Arctic Coast/Plains continue to remain dry outside of some very isolated snow showers. Scattered showers will remain predominantly rain with snow levels south of the North Slope generally remaining between 2000 and 4000 feet. Given the time of year with temperatures across much of our region south of the Brooks Range seeing highs hold steady well into the 50s and 60s, daily isolated thunderstorms will also be possible that will peak in coverage each afternoon and evening.

With this overall setup, southerly winds will remain strong through Alaska Range Passes and at Delta Junction for Tuesday and Tuesday night before weakening on Wednesday, with peak gusts around 40 to 60 mph. Farther north, another strong easterly wind corridor will be along the Arctic Coast Tuesday and Wednesday, with gusts to around 25 to 35 mph leading to localized blowing snow at times.

Looking ahead, models are showing increased confidence on another low pressure system working through the Aleutians into the Bering Sea for Thursday and Friday. This will continue to reinforce and support daily precipitation chances across Northern Alaska in addition to an increase in winds through Alaska Range Passes and at Delta Junction on Thursday. Precipitation amounts overall through the extended forecast continue to look light.

Coastal Hazard Potential Days 3 and 4...None

AFG WATCHES/WARNINGS/ADVISORIES

AK...Wind Advisory for AKZ837-849. Flood Watch for AKZ818. Flood Watch for AKZ829. Red Flag Warning for AKZ937. PK...Small Craft Advisory for PKZ801-850. Small Craft Advisory for PKZ802. Brisk Wind Advisory for PKZ815-861. Small Craft Advisory for PKZ816-817-854. Brisk Wind Advisory for PKZ851.