textproduct: Fairbanks

SYNOPSIS

Thunderstorms are expected in the SW Interior today, though should have minimal impacts. Delta Junction and Isabel Pass are expected to have fire weather concerns today and tomorrow with gusty winds and dry conditions for both afternoons. Coastal areas along the West Coast and North Slope continue to experience fog that is expected to continue through the weekend. Elsewhere, the warmest conditions so far this season are expected this weekend, with some areas in the Interior possibly seeing 80 degrees.

KEY WEATHER MESSAGES

Central and Eastern Interior... - Isolated to scattered thunderstorms are possible in the SW Interior today. Gusty and erratic winds as high as 35 mph are possible.

- Red Flag Warning for Delta Junction and Isabel Pass as winds increase and minimum RHs decrease to critical values Saturday afternoon, 20 to 30 mph sustained wind, gusts to 45 mph and RHs near as low as 20%. Sunday consists of stronger winds, 30 to 40 mph with gusts to 55 mph and RHs near 30%.

- Warm and dry conditions persist this weekend with the warmest temperatures of the year so far likely for the Interior. Some areas could see as high as 80 degrees for the first time this season.

- Monday will see gusty winds as high as 30 mph for the Western and Central Interior.

West Coast and Western Interior... - Isolated to scattered thunderstorms are possible in the SW Interior today. Gusty and erratic winds as high as 35 mph are possible. Areas of stratus on the West Coast are expected to persist through the weekend.

- Temperatures remain warm through the weekend with the warmest weather of the year so far expected in the Western Interior. Highs in the low to mid 70s with an isolated 80 possible. Seasonably warm along the West Coast. Highs in the 50s to near 60 from Wales northward, with 60s to near 70 south. 40s to near 50 in St. Lawrence Island.

- Widespread rain moves into the Western Interior Sunday night and continues through Tuesday with around 0.25 to 0.75" of rain possible. Wind gusts as high as 30 mph are possible on Monday.

North Slope and Brooks Range.. - Seasonably mild on the Arctic Coast with highs in the 30s and 40s through the weekend. Warmer in the Plains and Brooks Range with highs in the 60s and even 70s.

- Moderate to heavy rainfall looks to aim at the Brooks Range from Monday to Wednesday. Exact placement of the heaviest rain is uncertain but a widespread 0.50" to 0.75" of rain is expected with some of the localized highest amounts up to 1" or more possible.

- With the heavy rain and snow continuing to melt on top of the mountains, rivers are likely to rise, though ice has moved out of the area.

FORECAST ANALYSIS AND DISCUSSION

Upper-level ridging is expected to continue, but weaken, throughout the day today and into tomorrow, bringing mostly dry and warmer weather to the region and potentially the highest temperatures of the season. However, areas along the West Coast and North Slope continue to experience fog and is expected to persist through the weekend, limiting their high temperatures. Thunderstorms are possible today in the SW Interior and shift westward towards the YK Delta on Sunday. Showers are expected with these thunderstorms due to a front extending from the Gulf of Alaska that will stretch as far north as the Brooks Range. The heaviest precipitation is expected in the highest elevations, especially in the Brooks Range where some areas could see rainfall totals as high as 1" or more throughout the weekend.

A Red Flag Warning has been issued for Delta Junction today and tomorrow due to these warm, dry conditions, along with southerly winds through the Alaska Range. Min RHs on Saturday will be slightly lower then Sunday at 20 and 30%, respectively and winds will be stronger on Sunday at around 45 mph.

As upper-level troughing moves into the area Sunday night into the beginning of the week, widespread showers are expected for areas along the West Coast and Interior with totals ranging around 0.25 to 0.75". Strong wind gusts as high as 30 mph are possible as well, especially on Monday. These showers will bring our RHs up, but will end our period of warmer weather, at least for the time being.

FIRE WEATHER

Weak upper level high pressure takes hold of the state today allowing for warm and dry conditions this weekend. High temperatures across the Interior this afternoon will be in the low to mid 70s, with some spots seeing afternoon highs reaching near 80F. Clear skies will support min RHs as low as 20% to 25% across the Yukon Flats and Tanana Valley. A Red Flag Warning was issued for Isabel Pass and Delta Junction beginning today through Sunday evening for winds gusting up to 45 mph today and up to 55 mph Sunday afternoon. Min RHs at Delta Junction are expected to be their driest this afternoon with the strongest winds expected Sunday afternoon out of the south. Winds elsewhere will be fairly light and out of the east/southeast across the Interior, with winds expected to shift towards the south/southwest by Monday morning. Gusty diurnally driven winds are possible going into next week, especially at higher elevations. Thunderstorm chances remain low this weekend with a few very isolated storms possible in the Southern Interior and Lower Yukon/Upper Kuskokwim on Saturday, then across portions of the Western Interior and Brooks Range on Sunday. By Monday, the pattern trends towards wetter and cooler conditions as a low in the Gulf of Alaska advects anomalously high amounts of moisture inland. Widespread wetting rain chances increase over the Western Interior and Brooks Range early next week with much of the Central/Eastern Interior expected to remain mostly dry due to downsloping effects.

HYDROLOGY

Most of the North Slope Rivers have broken up with little to no impacts. Moving forward as summer arrives and temperatures rise, there is a potential for snowmelt rises. Near normal temperatures, which include above freezing overnight temperatures, are predicted as we enter next week.

Most of the remaining snowpack is in the foothills and mountains where temperatures will be highest. This could lead to rapid melt and river rises. We are also anticipating a widespread 1/2" to 3/4" of rain early next week which may exacerbate river rises since there will be a combination of snowmelt and rain runoff.

Most of the ice on the larger rivers has already moved out which leaves more room to accommodate the increasing snowmelt and rain. This contrasts with last year's late breakup when the snowmelt all entered the river systems while ice was mainly still in place.

Rising of water levels in rivers can be expected late this weekend or early next week.

EXTENDED FORECAST DAYS 4-7

Tuesday through Friday. Broad upper level troughing will continue on Tuesday, anchored by two H5 lows in the Chukchi Sea and Gulf of Alaska. The main trough axis will continue to lift northeast throughout the day, allowing for a more dominant ridge of high pressure to build in out of the southwest through the Bering Sea. During this timeframe, cooler temperatures and isolated to scattered rain showers chances will persist, with scattered to widespread showers in the Brooks Range where more moderate precipitation totals are expected. High confidence continues midweek as ensemble model guidance remains in very good agreement on that ridge of high pressure shifting northeast into Northern Alaska, allowing for the significant weakening and dissipation of troughing over our region. As a result, conditions will trend warmer and drier to finish out the week as temperatures return to holding more steady near seasonal norms. We will however keep around daily isolated to scattered shower and thunderstorm chances that will peak diurnally each afternoon and evening given antecedent conditions out ahead of the ridge with higher PWATs already in place.

Coastal Hazard Potential Days 3 and 4...None

AFG WATCHES/WARNINGS/ADVISORIES

AK...Red Flag Warning for AKZ937. PK...Small Craft Advisory for PKZ801-850.