textproduct: Fairbanks

SYNOPSIS

An active weather pattern continues across Northern Alaska today, as a front lifts north over the Interior towards the Brooks Range. Gusty winds across the Arctic Coast today could last for the next few days, leading to areas of blowing snow and wind chills as low as -20F. In the Interior, generally warm and mostly dry conditions are expected today. Southerly flow across the Alaska Range has resulted in gusty winds through the passes and in Delta Junction which will continue through this evening. Showers (mostly rain) will be possible in the northern Interior and adjacent coastal areas with a north-moving front through this morning, although accumulations will not be very heavy. Minor snow accumulations will be possible in the Brooks Range and on the North Slope through tonight. Cooler conditions will prevail today in the Central and Eastern Interior, with a warming trend resuming on Tuesday as the warmest temperatures so far this year for much of the Interior build in midweek. Conditions will trend dry across Northern Alaska Tuesday ahead of daily shower chances returning south of the Brooks Range starting Wednesday.

KEY WEATHER MESSAGES

Central and Eastern Interior...

- Scattered precipitation will be possible across the Interior today. Precipitation type should be mostly rain, apart from higher elevations where snow or a rain/snow mix could occur.

- Somewhat cooler temperatures are expected in the Southern Interior today, but highs will quickly rebound Tuesday and Wednesday, when they could reach into the low to mid 60s.

- Gusty NE winds continue across the northern Interior early this morning but will gradually diminish, becoming light by this evening. - A front will pass through the northern Interior today, bringing gusty southerly winds behind it. Southerly gap winds through the Alaska Range passes will continue today, with peak gusts of 50 to 65 mph possible.

- Red Flag Warnings and Wind Advisories are in place for the Delta Junction region south along the Richardson Highway today for gusty winds, low relative humidity, and dry fuels.

West Coast and Western Interior...

- A front will lift north across the northwestern Interior and adjacent coastal areas through late this morning, producing a band of precipitation which should be primarily rain.

- Warm, southerly flow will allow for highs in the upper 40s to near 50 in the Western Interior and in the 40s along the coast. A warming trend continues through the week, with much warmer temperatures in the mid to upper 50s on Tuesday and Wednesday in the Western Interior.

North Slope and Brooks Range..

- Monday morning, a front brings a band of snow across the Brooks Range, arriving north of the Range by the afternoon. Accumulations should be generally less than an inch. - Gusty winds continue across the North Slope today. Winds will be strongest along the Western and Eastern Arctic Coast where winds could peak upwards of 40 mph.

- Winds could remain elevated through at least Wednesday, leading to areas of blowing snow which could significantly reduce visibility. A Blizzard Warning has been issued for Point Lay through this afternoon due to blowing snow leading to visibility at or below a quarter mile.

FORECAST ANALYSIS AND DISCUSSION

Today through Wednesday Night. A ~1024 mb surface high occupies the Arctic north of Alaska and is driving southeasterly winds on the western Arctic Coast, turning easterly to northeasterly on the eastern Arctic Coast. This has resulted in blowing snow and very poor (at times blizzard) visibility conditions at Point Lay. Windy conditions on the Arctic Coast are likely to continue through much of the week, although they are likely to decrease enough on the western Arctic Coast this evening to reduce blowing snow concerns.

A cold, 517 dm upper low is parked over the northern Bering Sea, with associated troughing extending eastward across the midsection of Alaska. Moving through the day today, this troughing and a surface cold front will shift northward across the northern Interior and into the Brooks Range, with 850 mb temperatures falling to around 5 to 7C. With this transient cold air, temperatures in the Interior and on the West Coast will be a few degrees colder on Monday than they were on Sunday. The front will continue northward across the West Coast and Interior today, reaching the Arctic Plains/Coast by this evening into tonight. It will bring light snow on the North Slope, with not much more than about an inch expected in the Brooks Range, and minimal accumulations on the Arctic Coast.

Temperatures will quickly rebound south of the Brooks Range on Tuesday, with southerly flow across the Alaska Range and an amplified ridge building into the Interior from out of northwestern Canada. The base of this ridge will be in northern Mexico/the southwestern United States, where the height of the 500 mb level is likely to be around 590 dm on Tuesday. Heights will not be nearly that high in Alaska but could rise into the upper 540s or 550s dm near the eastern border. Corresponding increases in surface temperatures will support highs in the low to mid 60s across the Central and Eastern Interior with dry conditions. This will likewise support temperatures in the mid to upper 50s in the Western Interior. Southerly gap winds continue through the Alaska Range passes and will persist through Tuesday morning, after which they are likely to diminish, ending by Tuesday night/ Wednesday morning. Warm conditions will continue south of the Brooks Range on Wednesday, with 850 mb temperatures reaching to near 5C in the Middle and Upper Tanana Valleys and and over the Fortymile Country and near 0 elsewhere. Somewhat cooler/showery conditions will be possible in these areas from Wednesday evening/night into the late-week time frame as moisture moves in with southeasterly flow around the northeast fringe of an upper low near the AK Peninsula.

FIRE WEATHER

Compared to the last couple of days, weather activity will be on a slight downward trend. With the front from the gulf moving farther north, gap winds through the Alaska Range will continue to decrease throughout the day. Southerly flow is expected to persist through much of the week across the Interior. This, and weak ridging building up over the Al-Can boarder, will limit the chances for widespread showers. The next best chance for isolated shower will be for the Upper Tanana, Wednesday afternoon, when the upper-level pattern shifts southeasterly. Expect a warming and drying trend through the much of the week. Thunderstorm chances this week are minimal this week. However some models show a low chance for some on Wednesday, but they have not shown much run-to-run consistency. That said, this will continued to be monitored over the next several model runs.

HYDROLOGY

KOYUKUK RIVER

A Flood Warning is in effect for the Koyukuk River at Hughes for ice jam flooding. The Flood Watch for the wider area along the Koyukuk River near Hughes also remains in effect. Public and emergency manager reports continued flooding in low lying areas, including significant impacts to the airport and school property.

YUKON RIVER

The Yukon River breakup front is currently downstream of Rampart. The River Watch team will fly to Tanana today (Monday May 11th) to report on surrounding ice conditions. Updates will be posted as available. A Hydrologic Outlook is out for Rampart and Tanana.

KUSKOKWIM RIVER

A Flood Watch also remains in effect for the Kuskokwim River at McGrath for an ice jam. A Flood Advisory was issued for McGrath yesterday to capture minor flooding impacts. The public reported continued minor flooding impacts today that is currently not impacting any structures or main roads at this time.

CHENA RIVER

The Chena River has begun to respond to warmer temperatures with increased snowmelt leading to rivers running higher and gages getting closer or reaching action stage.

SALCHA RIVER

The Salcha River is expected to reach action stage later this week as warmer temperatures lead to increased snowmelt.

ADDITIONAL INFORMATION

Head to 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

Thursday through next Monday.

At the start of the extended forecast period, the pattern is dominated by an upper level high over the Arctic Ocean and a very large region of upper level low pressure stretching across the Bering Sea. A weak ridge attempts to push into Northern Alaska from Canada, but is halted by the other upper level features. Through the end of the week the upper level low attempts to move east into the Gulf of Alaska allowing the upper level high to start pushing into Northern Alaska. The majority of flow throughout the pattern lies on the south side of the upper level low and remains well to the south of Northern Alaska leaving the region with relatively gentle weather that slowly warms through the end of the week. The majority in variance in the forecast remains south of the region so the forecast remains fairly confident.

EXTENDED FORECAST DAYS 4-7

Thursday through next Monday.

At the start of the extended forecast period, the pattern is dominated by an upper level high over the Arctic Ocean and a very large region of upper level low pressure moving from the Bering Sea to the Gulf of Alaska. Higher pressure builds across Northern Alaska as the upper level low pushes further into the Gulf of Alaska. This keeps Northern Alaska relatively calm in terms of weather. The majority of variance in the forecast lies far to the south of the region so calmer weather with periods of east/northeasterly winds is very likely throughout the extended forecast period.

Coastal Hazard Potential Days 3 and 4...None

AFG WATCHES/WARNINGS/ADVISORIES

AK...Blizzard Warning for AKZ801. Wind Advisory for AKZ837-849. Flood Watch for AKZ828-852. Red Flag Warning for AKZ937. PK...Small Craft Advisory for PKZ801. Small Craft Advisory for PKZ804. Brisk Wind Advisory for PKZ809. Small Craft Advisory for PKZ812. Heavy Freezing Spray Warning for PKZ812. Brisk Wind Advisory for PKZ813. Brisk Wind Advisory for PKZ814-815-860. Small Craft Advisory for PKZ817. Small Craft Advisory for PKZ850. Brisk Wind Advisory for PKZ851-854. Brisk Wind Advisory for PKZ857. Brisk Wind Advisory for PKZ858. Brisk Wind Advisory for PKZ861.