textproduct: Fairbanks

SYNOPSIS

Broad scale troughing persists over the state as a low pressure system in Bristol Bay gradually moves east into the Gulf of Alaska by Thursday. A front near the northwest portion of Alaska is expected to move southeast through the weekend. Scattered showers and isolated thunderstorms are possible through the early weekend, with coverage primarily from the Yukon Flats over towards the Steward Peninsula and down to the Alaska Range. As high pressure builds over Siberia and the Canadian Yukon later this week, warmer and drier weather is expected across Alaska.

KEY WEATHER MESSAGES

Central and Eastern Interior... - Isolated thunderstorms and scattered showers are expected to continue across most of the Interior throughout the week. For this afternoon, highest chances are from the Yukon Flats over to the Steward Peninsula. Chances expand down the the Alaska Range Thursday.

- High temperatures will remain in the low to mid 60s through the weekend with a warming trend expected early next week.

- Moderate showers are possible for the Tanana Valley on Friday.

West Coast and Western Interior... - Scattered showers and isolated afternoon thunderstorms continue across the Western Interior and parts of the Seward Peninsula this week. Showers and thunderstorm chances decrease from north to south through the end of the week.

- Gusty north/northeast winds are continuing through the Bering Strait today through Friday with winds gradually weakening by Thursday. Gusts as high as 30 to 40 mph are possible.

- Temperatures will remain in the upper 50s to low 60s through the weekend before steadily increasing early next week.

- Patchy fog is possible across the West Coast tonight into Thursday morning.

North Slope and Brooks Range... - Slightly cooler than normal temperatures continue across the North Slope with highs in the mid 20s and lows in the mid teens. - East/northeast winds will shift towards the south/southwest by the late weekend.

- Gusty northerlies through mountain passes in the Brooks Range are expected Thursday into Friday.

- Low clouds and patchy fog are expected to persist across the North Slope through the week with gaps in the clouds possible Friday. Clearer skies are possible this weekend into next week as winds weaken and offshore flow sets up along the coast.

FORECAST ANALYSIS AND DISCUSSION

Through Friday: Several features of note will drive the mostly benign pattern through the end of the work week. A broad trough and upper level low near the Bering will be pushed into the central gulf by a building ridge near Siberia. Furthermore, near the eastern North Slope, a digging trough will be pushed eastward by the aforementioned building ridge to the west. A few surface features will result from this pattern: a front looks to slowly descend down from the NW portion of the state, moving SE towards the Alaska Range by Friday night. This front is associated with the digging trough in the eastern north slope, resulting in drier weather from north to south, and gustier conditions. With the upper level low in the northern gulf and southeasterly to easterly flow into the interior, rain chances ahead of the front, while coming to an abrupt end behind the front.

Numerous to widespread rain showers with isolated thunderstorms ahead of the front will push southward through the end of the week. Moderate rain showers are possible in the Tanana Valley on Friday, due to moisture streaming in from the east, with northeast flow from the low in the gulf causing orographic lifting up against the northern side of the Alaska Range. It is possible to see rain showers with rain rates exceeding 0.1 in/hr.

FIRE WEATHER

A low pressure system dropping south toward the northern coast maintains scattered convective showers and isolated thunderstorms across the Interior, with brief wetting impacts and intermittent RH recovery in areas of activity. As this Arctic low weakens and the low in the Gulf of Alaska exits east, shower and thunderstorm coverage become more confined and gradually shifts southward, with diminishing activity across the region.

Winds are expected to remain generally light across the Interior as weak pressure gradients limit widespread sustained wind concerns inland. However, terrain-driven channeling continues to support localized northerly gap winds through the Brooks Range and into the Upper Koyukuk Valley and across the Dalton Highway Summits. As a surface high pressure system approaches from the Arctic, stronger winds from the east drive across the Yukon Flats and Forty Mile Country later this week. Along the West Coast and through the Bering Strait, tighter pressure gradients between the Arctic low and the high pressure over Siberia support stronger winds across the strait and in western communities along the coast. As the pattern evolves, winds remain variable but generally light inland while coastal wind regimes persist. Temperatures remain seasonable and relatively moderate throughout the week with no significant warming trend expected yet, though higher temperatures appear likely starting next week.

HYDROLOGY

River Watch has concluded as of 8 AM Wednesday. Ice continues to move through the channels into the mouth with relative ease with upstream ice moving unhindered. Residents should still use caution near the banks as the ice run continues to be very dynamic and water levels can fluctuate quickly. Flood warnings remain in effect for St. Mary's, Emmonak, and Alakanuk, and are set to expire on time at 5 pm Wednesday.

St. Mary's: At 840pm, flood waters continue to slowly recede. Due to the extensive high water and inundation, this process could take several days. Residents should use caution in and around areas that were flooded.

Emmonak: Waters continue to receed. The roads to the airport remain impassable by vehicle at this time. Residents should use caution in and around high water.

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

EXTENDED FORECAST DAYS 4-7

Saturday through Tuesday. Saturday see a continuation of the upper level low near the northern gulf with broad troughing across the state. Guidance has generally come to the consensus that the upper level low will dig south by Monday, driven out by ridging from both western Canada and near Siberia. As the front from the north departs south of the Alaska Range, temperatures are expected to warm in the Interior ranging from the upper 60s to mid 70s for highs, with around a 70-80% likelihood of exceeding 70F by June 2nd. Outside of the Interior, temperatures are also expected to broadly warm. On average in Fairbanks, our first 70F day is May 20th so while we are a bit behind average, we are expecting to be ahead of the record latest first 70F day which was set last year on June 11th. Overall, we are looking at a warmer and drier start to June across Northern Alaska as a ridge of high pressure establishes itself in the Bering and pushes the more favorable storm track down farther to our south.

Coastal Hazard Potential Days 3 and 4...None

AFG WATCHES/WARNINGS/ADVISORIES

AK...Flood Watch for AKZ825. PK...Small Craft Advisory for PKZ801. Small Craft Advisory for PKZ806-811-854. Brisk Wind Advisory for PKZ807-810-856. Small Craft Advisory for PKZ812-857. Small Craft Advisory for PKZ817. Small Craft Advisory for PKZ858.