textproduct: Fairbanks

SYNOPSIS

An upper-level, arctic trough continues to rotate over the North Pole, swinging a series of shortwaves across the state from the NW. This will continue to provide chances for snow across the North Slope through the weekend. In addition, this will continue to allow northwesterly flow to continue across the state which will set up the potential for seasonably cooler temperatures as more abundant shortwaves move south across the West Coast. Meanwhile, another low will be moving east along the south side of the Aleutians. This will bring the next slight chance for isolated thunderstorms to the Upper Tanana on Saturday.

KEY WEATHER MESSAGES

Central and Eastern Interior... - Warmer temperatures reaching the low to mid 70s over most of the Interior valleys through the end of the week.

- Scattered showers are possible for the Alaska Range, Eastern Interior, and Northern Interior through the weekend and early next week.

- Below normal temperatures this weekend, going into next week. Minimum temperatures may get as low as the mid to upper 30s.

West Coast and Western Interior... - Warmer temperatures with highs in the low to mid 70s through the end of the week.

- Strong west to northwest gusts Kotzebue Sound through Friday night with gusts up to 30 mph expected. Gusts are expected to relax overnight before picking up again during the day.

- Below to much below normal temperatures this weekend and going into next week. Minimum temperatures may get as low as the mid to upper 30s.

North Slope and Brooks Range.. - Below average conditions are expected to persist with temperatures mostly between 30 and 40 degrees through Friday.

- Isolated snow showers expected to continue across the North Slope through the start of the weekend. Accumulations around an inch with higher amounts at elevation in the Brooks Range.

- Gusty north/northwest winds, up to 30 mph, will remain in place over the Brooks Range through Friday night.

- Below to much below normal temperatures this weekend and going into next week. Minimum temperatures possibly dropping below 20 degrees along the coast.

FORECAST ANALYSIS AND DISCUSSION

Fairly benign weather continues across most of the state. The main driver for this forecast period is an Arctic low, currently sitting over the North Pole, and high pressure out in the Bering. This is setting up west/northwest flow across the majority of the state, which will eventually lead to seasonably cooler temperatures by the end of the weekend. Meanwhile, a series of weak shortwaves embedded within the flow will move SE from the Chukchi, over the Brooks Range, and into the NE portion of the Interior. This will continue to provide chances for snow showers across the Arctic Plains over the next several days. A slight up- tick in the westerly winds is possible along the Arctic Coast today as the first shortwave moves across the North Slope. As the week comes to an end, a more prominent shortwave will move south along the West Coast. This will help to broaden the troughing across the state. In addition, the Arctic low will slowly shift south, closer to the Arctic Coast. Another low will be moving east, south of the Aleutians throughout the weekend. Some of the energy from this low will work its way across the Upper Tanana on Saturday bringing a slight chance for an isolated thunderstorm in the afternoon.

FIRE WEATHER

Upper-level ridging is expected to persist through the rest of the week, leading to a decrease in shower and thunderstorm activity. Light, isolated showers are possible, but chances of wetting rain and thunderstorms remain unlikely. High temperatures are expected to remain in the 60s and 70s everywhere except the North Slope where areas will remain in the 20s and 30s. Minimum relative humidities are expected to generally be in the 30% range, except the Tanana Valley, Fortymile Country, and the Yukon Flats where 20% is possible.

A pattern shift is expected towards the end of the week and into the weekend as upper-level troughing builds into the state from the north, leading to the increased possibility of isolated showers and thunderstorms returning as shortwaves move into northern Alaska. These showers will also lead to an increase in minimum relative humidities and decreasing high temperatures this weekend and into the beginning of next week.

HYDROLOGY

No changes from the previous hydro forecast discussion.

Sagavanirktok River: Some overflowing is occurring; however, breakup along the Sag River has not begun yet. Temperatures continue as below normal, around the low 30s for a high near the coast and the mid to upper 30s for the northern Brooks Range. Going into the weekend and into next week, much below normal to possibly record breaking temperatures with lows possibly below 20 degrees and high temperatures not exceeding freezing, except near the Brooks Range where temperatures may reach the upper 30s.

EXTENDED FORECAST DAYS 4-7

At the start of the extended forecast period Sunday a very large upper level low over the high Arctic continues to push south towards the North Slope. This low brings very cold air for the time of year over much of Northern Alaska and puts a definitive end to the warmer weather of the previous week. High temperatures fall into the upper 50s to low 60s across much of the Interior and fall below freezing along the Arctic Coast. Interior valleys could see frosts with low temperatures falling into the 30s. If skies are clear enough temperature inversions will develop that may bring low temperatures in the deepest valleys near freezing.

Otherwise daily afternoon showers and the occasional extremely isolated afternoon thunderstorm are possible across the Interior under this pattern. Heavier and more widespread precipitation is most likely only when stronger shortwave features rotate around the Arctic low into the region. When these pass through northwesterly winds along the West Coast, particularly the Chukchi Sea Coast, and westerly winds across the Arctic Coast are expected to increase. Combined with the low temperatures unseasonably cold wind chills are possible across the Arctic Coast early next week. The timing of these stronger shortwave features is still subject to change, but the current forecast is predicting one passing through the region Sunday afternoon through Monday which is expected to bring those more widespread showers and stronger winds.

Coastal Hazard Potential Days 3 and 4...None

AFG WATCHES/WARNINGS/ADVISORIES

AK...None. PK...Small Craft Advisory for PKZ801. Small Craft Advisory for PKZ805-806-853-854-856. Brisk Wind Advisory for PKZ807. Brisk Wind Advisory for PKZ808. Brisk Wind Advisory for PKZ809. Brisk Wind Advisory for PKZ810. Brisk Wind Advisory for PKZ814-860. Brisk Wind Advisory for PKZ815. Small Craft Advisory for PKZ850. Brisk Wind Advisory for PKZ855. Brisk Wind Advisory for PKZ861.