textproduct: Fairbanks

KEY MESSAGES

Central and Eastern Interior... - North of the Alaska Range, rain and snow chances increase this evening across the central interior then diminish Friday night. Mainly snow is expected north of the Yukon River with rain farther south below 2000 ft. There is a chance for freezing rain along a southwest to northeast oriented transition zone.

- Downslope southerly winds keeps the southeast interior including Fairbanks mostly dry. Snowfall amounts range from 0-4" across the interior valleys with 4-8 inches for the Dalton Highway summits and up to 12 inches in the Brooks Range.

- For the Alaska Range, southerly upslope flow brings moderate snow to the southern slopes tonight into Saturday with 4-8 inches for the Parks Highway and 6-12 inches for the Richardson Highway. Wind gusts up to 35 mph may result in areas of blowing snow.

- Southerly gap winds are expected for the Alaska Range passes with gusts up to 70 mph for Windy Pass and up to 85 mph possible for Isabel Pass north of Trims Camp.

- Unseasonably mild conditions continue through Saturday with highs in the mid 30s to near 40 and lows in the 20s and low 30s. These temperatures are about 10 to 15 degrees above the late October seasonable averages.

West Coast and Western Interior... - A broad swath of precipitation spreads northeast tonight with numerous showers along the West Coast for Friday and isolated showers further inland that gradually diminish over the weekend.

- Snow levels decrease from about 2kft southeast of the Seward Pen to around 500ft over the Koyukuk and at the surface over the western Seward Pen. Below about 500ft receives up to 3 inches of snow, 3-7 inches for higher elevation ridges, and locally up to 10" for the highest elevation mountains.

- A cold front briefly shifts east Saturday into Sunday bringing drier weather and more seasonable temperatures until the next Bering Sea low brings a return to much above normal temperatures and precipitation chances early next week.

North Slope and Brooks Range... - Snow is expected across the West-Central Brooks Range tonight through Friday then expanding northwest across the Romanzof Mountains and Chukchi Coast on Friday.

- Snowfall amounts are generally less than 4 inches except for the higher elevation portions of the Brooks range where 4-12 inches are expected. Snow chances end by Monday morning.

- Unseasonably warm temperatures continue as highs in the 30s and lows in the 20s persist across most of the North Slope through Saturday, maintaining well above normal thermal trends for late October.

SYNOPSIS

Ex-Typhoon Champi will be the driving factor of Alaska's weather into this weekend. As this system tracks east toward Bristol Bay through Friday, a tight pressure gradient forms over Alaska. This will result in gusty south winds, especially for the Alaska Range Passes that will persist through Saturday. Associated with these gusty winds is high surf especially during the afternoon high tides through Friday near Hooper Bay. A warm front tracks northeast across Alaska this weekend, bringing with it another round of rain for the YK-Delta and lower elevations across the interior and snow for the northern interior and higher elevations. As a result of the southerly flow associated with this system, the southeast interior including Fairbanks remain mostly dry. The North Slope also stays mostly dry, but chances of light snow spread north of the Brooks Range Friday through the weekend. The storm system weakens over the weekend leading to more isolated rain/snow showers for the West Coast/Western Interior, especially near the systems cold front.

SHORT TERM.../Through Saturday/

An amplified upper level pattern due to the remnants of Typhoon Champi and downstream ridging result in another period of active weather through this weekend. The primary weather impacts are associated with an expansive precipitation shield shifting northeast across Northern Alaska embedded within a Chinook pattern. The warm origins of the this system results in another period of mixed precipitation. The Chinook pattern keeps most of the south-central and eastern interior dry where downslope flow prevails and results in warmer temperatures mainly at or above 30F through Friday. Farther north and west, precipitation may begin as snow at lower elevations, but it is expected to transition to rain south of the Yukon Valley. Otherwise, elevations above 1500-2000ft should stay predominantly snow with up to 4 inches across the interior highlands and up to 12 inches across the west-central Brooks Range. By midday Friday a warm front extends from south-central AK toward the Chukchi coastline and a cold front extends south from there along the West Coast. The cold front focuses precipitation chances Friday night through Saturday as it slowly shifts east, bringing a more seasonable air mass.

The Alaska Range is the other noteworthy area of weather impacts with southerly upslope flow focusing snowfall for the south-facing slopes. Snowfall amounts range from 6 to 12 inches within the passes along the highways with higher amounts at higher elevations. Very strong winds are expected through both mountain passes with Windy Pass already gusting up to 67 mph and Isabel gusting up to 64 mph. With a cross-barrier pressure gradient around 8-10 mb and 500 mb flow nearly parallel to the passes gusts over 70 mph are likely tonight and Friday before diminishing Friday night.

COASTAL HAZARD POTENTIAL

As the remnants of Typhoon Champi continue east tonight into Friday, high surf is expected with elevated sea levels of 2.5 to 3.5 feet above the normal high tide line. While onshore flow persists, these higher water levels contribute to beach erosion and high surf that may bring water to nearby low lying areas, especially during the evening high tide cycles. Ex-Typhoon Champi weakens and tracks southeast toward the Gulf of Alaska late this week leading to improving conditions.

HYDROLOGY

Repeated rounds of precipitation due a series of storm systems over the past week already resulted in elevated river and stream levels, especially for the Seward Peninsula. The remnants of Ex-Typhoon Champi brings another round of precipitation up to 0.5" resulting in river levels remaining elevated this weekend. While the water levels remain elevated, there are no flooding concerns at this time.

AFG WATCHES/WARNINGS/ADVISORIES

AK...High Surf Advisory until 1 AM AKDT Saturday for AKZ825. High Wind Warning until 5 AM AKDT Friday for AKZ847. Winter Weather Advisory until midnight AKDT Friday night for AKZ848. High Wind Warning until 7 AM AKDT Saturday for AKZ849. Winter Weather Advisory from 10 PM this evening to 7 AM AKDT Saturday for AKZ850. MARINE...Small Craft Advisory until 1 AM AKDT Friday for PKZ801-802-804. Small Craft Advisory until 7 PM AKDT this evening for PKZ803- 812>815-859>861. Small Craft Advisory from 10 PM this evening to 4 AM AKDT Friday for PKZ803. Small Craft Advisory until 4 AM AKDT Friday for PKZ805-852-853. Small Craft Advisory until 4 PM AKDT this afternoon for PKZ806- 858. Small Craft Advisory from 7 PM this evening to 6 PM AKDT Friday for PKZ806-807. Small Craft Advisory from 7 PM this evening to 1 AM AKDT Friday for PKZ808. Small Craft Advisory from 7 PM this evening to 4 AM AKDT Friday for PKZ809-855. Small Craft Advisory from 4 AM to 10 AM AKDT Friday for PKZ810. Small Craft Advisory from 4 AM to 6 PM AKDT Friday for PKZ811- 857. Brisk Wind Advisory until 4 PM AKDT this afternoon for PKZ814- 815. Small Craft Advisory from 10 AM to 1 PM AKDT Friday for PKZ814. Small Craft Advisory until 6 PM AKDT Friday for PKZ816-851. Gale Warning from 1 AM to 4 AM AKDT Friday for PKZ816. Gale Warning from 7 AM to 1 PM AKDT Friday for PKZ816. Small Craft Advisory until 6 PM AKDT Friday for PKZ817-854. Gale Warning from 10 PM this evening to 6 PM AKDT Friday for PKZ817. Small Craft Advisory until 10 PM AKDT this evening for PKZ850. Small Craft Advisory from 4 PM to 6 PM AKDT Friday for PKZ850. Gale Warning from 7 AM to 4 PM AKDT Friday for PKZ851. Gale Warning from 4 AM to 6 PM AKDT Friday for PKZ854. Small Craft Advisory from 10 PM this evening to 6 PM AKDT Friday for PKZ856. Small Craft Advisory from 1 PM to 6 PM AKDT Friday for PKZ858- 859. Brisk Wind Advisory until 7 PM AKDT this evening for PKZ859>861. Brisk Wind Advisory from 4 PM to 6 PM AKDT Friday for PKZ859. Small Craft Advisory from 1 PM to 4 PM AKDT Friday for PKZ860.