textproduct: Fairbanks

SYNOPSIS

The pattern of cool temperatures across Alaska with showers in the Interior continues through Saturday morning, after which a system arrives from the south to bring in warmer temperatures and more extensive precipitation for areas south of the Brooks Range. The North Slope remains colder and relatively dry through the weekend, with low stratus clouds from onshore flow. Winds across the state become primarily northerly Thursday night, and will strengthen along the Western and Northern Coasts and over the Brooks Range Friday night.

KEY WEATHER MESSAGES

Central and Eastern Interior...

- Thursday and Friday, scattered rain/snow in the Southern and Eastern Interior with potential for a shift to snow overnight, especially at higher elevations. Minimal snowfall accumulations are expected.

- Friday night through Saturday, chances for precipitation become more widespread across the Central and Eastern Interior. Precipitation type should be mostly rain, apart from higher elevations where snow or a rain/snow mix could occur.

- Cooler temps expected through Friday, likely only reaching the mid/upper 40s Thursday. Similarly, low temperatures will cool into the low 30s, allowing for some patchy areas of frost to develop overnight.

- Winds through the Alaska Range and into the southeast Interior will be southerly Thursday before weakening and turning easterly overnight. Winds across the rest of Interior will be easterly to northeasterly Thursday before strengthening on Friday.

West Coast and Western Interior...

- A cool, dry air mass has settled over the western half of the state, resulting in cooler temperatures through the weekend. High temperatures will struggle to reach the 40s in the Western Interior through Thursday and will be colder along the coast. Lows will range from the upper teens across the Seward Pen and Kotzebue Sound to the low 20s in the Western Interior.

- Strong northerly winds begin to develop through the Bering Strait Thursday, dropping slightly overnight before restrengthening again Friday with gusts up to 30 mph through the Strait.

- Showers becomes more likely in the Western Interior Friday night/ Saturday morning. Precipitation type will become snow or a rain snow mix overnight. Amounts will be light, less than a tenth of an inch liquid.

- Low stratus clouds remain along parts of the coast and areas of low clouds will likely persist through Thursday.

North Slope and Brooks Range...

- Snow showers have ended north of the Brooks Range to the Coast. However, the Central and Eastern Brooks Range will continue to see chances for snow through the weekend. Daily snow accumulations look to be up to 3 inches in the heaviest places.

- North to northeast winds, at times gusty, will develop Thursday evening and strengthen gradually through Friday night. There may be enhanced northerly gap winds trough Central Brooks Range Passes on Friday with gusts up to 30 mph.

- Northeasterly winds around Point Hope and Cape Lisburne will peak at over 40 mph Saturday into Sunday.

- Northerly onshore winds will keep the Arctic Coast socked in with low stratus clouds. It will also result in max temperatures in the low 20s and teens above through the weekend.

FORECAST ANALYSIS AND DISCUSSION

An upper-level low descending over Western Alaska continues to pull cold air over most of Alaska, but especially the West Coast. On the eastern side of the low, southerly flow will support showers in the Interior Thursday and Friday. It is also causing heavier snow in the Eastern Alaska Range, which should taper off through Thursday morning. At the surface, high pressure is present in the Bering Strait from the Chukchi Sea, and over southeast Alaska. Through the Bering Strait and into the Western Interior, northerly winds will begin to strengthen through the day Thursday. High pressure builds in over more of the North Slope resulting in northeasterly winds across most of the Interior by Thursday afternoon. The high surface pressure over the Panhandle will allow southerly winds in the Southeast Interior to overpower the northeasterly gradient producing southerly winds through the Alaska Range and into the Southeastern Interior. Models are showing the showers expected this afternoon primarily forming to the north of where these two wind fields meet, over the White Mountains east of Fairbanks.

Friday the upper-level pattern remains mostly the same with the 523 dam upper-level low now over the southwest Interior, generally colder temperatures through Northern Alaska and showers in the Interior which should move to the northwest to include the Central and Eastern Brooks Range and more of the Western Interior. However, a new low is approaching the Gulf of Alaska from the South and the leading edge of that system looks to begin impacting our area Friday night. The of the surface pressure gradient from the high pressure to our north and approaching low from the south results in an increase of winds across the state. Wind direction in generally easterly to northeasterly, but becomes more northerly closer to the West Coast and through the Bering Strait. We could see enhanced gap winds through the Brooks Range Passes, although the direction of the winds appears more easterly at this time, which would reduce the impacts.

Saturday morning, the first impacts of a low coming up from the Pacific will be felt in the southeast Interior. A broader swath of moisture than the showers we've had the previous couple days travels from southeast to northwest through the day Saturday. This advection of warm moist air will also serve to warm things up in the Interior. The North Slope and West Coast will have easterly and northerly winds strengthen respectively, with particular note around Point Hope and the eastern Arctic Coast. These stronger colder winds will reduce the warming effect of the arriving air mass and keep them cooler still. The Saturday system also brings some of the first decent chances for convection. Models are putting good chances for thunderstorms across the border which could carry over into the Southeastern Interior.

FIRE WEATHER

General troughing across the state will continue to allow for isolated precipitation chances across the Interior through the rest of the week. Temperatures are expected remain on the cooler side with highs mostly in the 40s today and into the low 50s by Friday. This weekend will likely see higher temperatures, with some areas possibly reaching 60. Areas that see a quick warm up, especially this weekend, may also see quick drops in RH as well. Minimum RHs are expected to be between 30% and 40% through the end of the weekend. Generally light winds are expected today, though southerly winds could be gusty in the Yukon Flats, YK Delta, and SW Interior on Friday. Thunderstorms may be isolated through the rest of the week, but possibly more scattered on Saturday in the SE Interior and on Sunday in the White Mountains and the areas west and east of town.

HYDROLOGY

Breakup continues along the upper Yukon as Eagle broke up earlier this week and the breakup front could reach Circle as early as tonight. The exact timing will depend on ice jams forming and releasing as the breakup front moves down river. Upstream of Eagle the river continues to breakup. so additional delayed ice runs will happen there in the next few days.

Elsewhere rivers continued to rise with several locations moving into action stage by Wednesday afternoon. As such river flood watches have been issued for areas surrounding Eagle, Circle, and the Tanana for Manly Hot Springs.

EXTENDED FORECAST DAYS 4-7

Sunday to Wednesday The pattern will be changing as an Omega block extending from Western Alaska to Central Siberia breaks down. First and foremost, an energized front will lift north on Sunday bringing our highest chances for thunderstorms in the Interior thus far. Otherwise, a high will drift north over the Arctic and by Sunday, it will be around 1025mb, north of Utqiagvik. Farther south, a low in the Gulf of Alaska will move north into South-Central. This low will weaken and push a front over the Alaska Range and into the Interior promoting gusty southerly winds through the Alaska Range Passes as well as breezy south winds in the Interior. Isolated to scattered rain/snow showers will be possible in the Interior on Monday. On the North Slope and in the Brooks Range, expect continued winds from the east/northeast with chances for snow, mainly in the Brooks Range through most of the forecast period. One thing to note is after Monday, confidence in the forecast is much lower but it does appear that there will be a weakening low moving east near the Aleutians. Depending on how far east it gets, this could bring rain and snow chances to the West Coast with a slight easterly wind. Otherwise, expect breezy conditions in the Interior with continued chances for showers.

Coastal Hazard Potential Days 3 and 4...None

AFG WATCHES/WARNINGS/ADVISORIES

AK...Flood Watch for AKZ833. Flood Watch for AKZ835. Flood Watch for AKZ846. PK...Heavy Freezing Spray Warning for PKZ812. Brisk Wind Advisory for PKZ815-861.