textproduct: Fairbanks

KEY MESSAGES

Central and Eastern Interior... - Snow showers continue through Wednesday night for areas east of FNSB and Alaska Range passes, with drier weather for Thursday.

- Temperatures will continue to be cool through Thursday with highs in the low to mid 30s. A warming trend is expected to settle in by Friday, before cooler weather returns early next week.

- Gusty south winds develop through the AK Range Friday night, potentially upwards of 60-70 mph on Saturday.

West Coast and Western Interior... - The main story is a Bering Sea low which will bring strong wind and minor coastal impacts Thursday into Friday. More elaboration about the coastal impacts in the coastal section.

- South/southeast winds begin to increase across the West Coast late Wednesday night into Thursday. Maximum wind gusts are expected to be between 45 and 65 mph, with the strongest winds expected offshore.

- Multiple rounds of precipitation are expected, with the bulk of it on Friday. Precipitation will be mostly rain for the southern half of the West Coast and mostly snow for the northern half.

- 10" to 14" of snow expected in the higher terrain North of the Kobuk Valley. Elsewhere, 2" to 4" can be expected.

North Slope and Brooks Range... - The cold front will continue to provide light snow showers for the eastern Brooks Range through Wednesday night. Up to 1" of additional snow is possible.

- Temperatures continue to remain cold with highs in the 20s and lows in the upper single digits to low teens.

- Strong south/southeast winds increase across NW Arctic Coast with gusts up to 60 mph likely on Friday. Periods of rain likely along the Chukchi Sea Coast Friday/Saturday with snow in the Western Brooks Range. Totals of 10-14 inches in the Western Brooks Range.

- Southerly winds increase on Saturday with gusts upwards of 45 mph possible in Atigun and Anaktuvuk Passes and 30 mph along the Arctic Coast.

SYNOPSIS

Snow showers depart off to the east through Thursday, ushering in a period of drier weather for the Central and Eastern Interior which lasts through the remainder of the week (and for the eastern interior, potentially the weekend. The Western half of the area will see a very different story. A strong front moves in from the Bering Sea, bringing with it elevated water levels, high winds, rain and snow. High Surf and Coastal Flood Advisories are in place, along with High Wind Warnings. The majority of the snow expected to fall will occur in the Western Brooks Range, where winter storm warnings have been issued. The low will slowly weaken over the Bering through early next week, before another low moves up from the South for Tuesday and Wednesday.

SHORT TERM /THROUGH SATURDAY/

Snow shower activity has mostly subsided in the Interior as the cold front continues to weaken and move east into Canada. Another weaker front is currently moving east over the Central Interior, but isn't expected to produce any precipitation. An upper level ridge is building over the West Coast, which is forcing both fronts east as well as bringing clear and calm conditions to the West Coast. This ridge moves east into the Interior Thursday and before slowly shifting east into Canada by Saturday.

A group of weaker surface lows phase together in the Western Bering (roughly 500-700 miles west of Mainland Alaska) and deepen to about 950 mb on Thursday. Fortunately, the ridge over Alaska forces the low to stall in the Western Bering while it weakens through Saturday. Even with the low several hundred miles away, the pressure gradient is steep enough to support a steep pressure gradient along the Bering from St. Lawrence Island through to the Western Arctic Coast. The strongest winds (gusts up to 65 mph along the coast are expected will be southeasterly before/while the warm front associated with the low passes over the region on Thursday into Friday. Winds become southerly and calm slightly after the warm front passes, but remain stronger through Saturday. Some water rises are expected along with these stronger winds starting Friday, see the Coastal Hazards Section for more detail.

This low pressure also pulls a swath of moisture from the subtropics (about 35 degrees north) up into the Gulf of Alaska. The most concentrated moisture will stay south of Mainland Alaska, but a portion of that moisture is pulled up the West Coast and into the Southwestern slopes of the Brooks Range. The warmth associated with this subtropical moisture will raise snow levels, so most of this precipitation will fall as rain on the West Coast and Western Interior, with totals in the 0.25"-0.5" range between Thursday afternoon and Saturday evening. Totals up to 1" are possible along higher terrain in the Nulato Hills and Seward Peninsula due to upslope flow. The Southwestern Slopes of the Brooks Range will also get upslope, but temperatures will be cold enough to support snow above about 1500 ft. Snow totals in the region will be in the 3"-6" range, with totals in the 6"-12" over the higher peaks between Thursday evening and Saturday morning.

Both the upper and surface lows continue to shift eastward Friday evening into Saturday. As the upper level low shifts east, flow becomes easterly over the Alaska Range. As the surface low shifts east, a surface pressure gradient begins to steepen along the passes, especially in Isabel Pass. Southerly gap winds in both passes pick up Friday evening into Saturday. Gusts will be stronger in Isabel Pass due to the steeper gradient (there is stronger high pressure to the south/southeast compared to Windy Pass), with gusts up to 70 mph possible.

LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/

A once powerful low by the Kamchatka Peninsula will be on a weakening trend as it occludes and meanders into the central Bering Sea through early next week. As the low weakens, elevated water levels across the west coast will continue to slowly trend back downwards Sunday. Precipitation will become increasingly spotty as the decaying front tries to move into the central interior, with only minimal precipitation chances expected through the early week for the FNSB and areas east. Some minor snow accumulations are possible for the Central and Eastern Brooks Range, but the by now moisture deprived front will lack the moisture for anything more than this. The strengthening pressure gradient will however bring Chinooking winds and downsloping from the AK Range into the Upper Tanana Valley and the Fortymile country. This will not only contribute to windy conditions through the weekend for the AK Range, but also to warmer temperatures for the eastern interior as adiabatic and diabatic heating related thermodynamics take hold.

A low developing along the triple point of what's left of the front south of the state will move north, but will largely dissipate moving up into south central through Sunday. By Tuesday, the low in the Bering will have decayed into a remnant trough, which will be absorbed by another low approaching Alaska. This low, in contrast to recent system, will move up from the S. Ensemble guidance is split on whether to take this next system into either Bristol Bay or the Gulf but in either case the main impact will be another round of rain and breezy conditions.

Coastal Hazard Potential...Still expect fairly minor coastal impacts from Thursday onwards through the weekend as a front moves into the West Coast. While water levels will be elevated, the south/southeast nature of the prevailing wind direction will keep the worst impacts at bay for most areas, with high surf advisories prevailing for most of the coast. Some coastal flood advisories have been issued for the southern Seward Peninsula, along with Hooper Bay. While water levels will peak during high tide Thursday afternoon, anticipate that levels will still remain somewhat elevated for many locations through the weekend as south/southeast flow persists.

HYDROLOGY

No hydrologic concerns are expected.

AFG WATCHES/WARNINGS/ADVISORIES

AK...High Wind Watch from Thursday morning through Friday morning for AKZ801. High Surf Advisory from 10 AM Thursday to 4 AM AKDT Saturday for AKZ801-815-820-824. High Surf Advisory from 1 PM Thursday to 4 AM AKDT Saturday for AKZ818. High Wind Warning from 8 AM Thursday to 1 AM AKDT Friday for AKZ820-821. Coastal Flood Advisory from 10 AM Thursday to 4 AM AKDT Saturday for AKZ821-822. High Wind Watch from Thursday morning through late Thursday night for AKZ822-823. Coastal Flood Advisory from 7 AM Thursday to 4 AM AKDT Saturday for AKZ825. High Wind Warning from 1 AM to 10 PM AKDT Thursday for AKZ827. High Wind Watch from Friday afternoon through late Saturday night for AKZ847-849. MARINE...Small Craft Advisory from 1 AM to 6 AM AKDT Thursday for PKZ801-802-805-810-853-856. Small Craft Advisory from 4 AM to 6 AM AKDT Thursday for PKZ803-808-809-852-855. Small Craft Advisory from 10 PM this evening to 6 AM AKDT Thursday for PKZ806-807-850-854. Gale Warning from 4 AM to 6 AM AKDT Thursday for PKZ806-850- 854. Small Craft Advisory from 4 PM this afternoon to 6 AM AKDT Thursday for PKZ811-857. Small Craft Advisory from 4 PM this afternoon to 4 AM AKDT Thursday for PKZ816-817. Gale Warning from 10 PM this evening to 6 AM AKDT Thursday for PKZ816. Gale Warning from 1 AM to 6 AM AKDT Thursday for PKZ817. Small Craft Advisory until 1 AM AKDT Thursday for PKZ851. Gale Warning from 7 PM this evening to 6 AM AKDT Thursday for PKZ851. Storm Warning from 4 AM to 6 AM AKDT Thursday for PKZ851. Small Craft Advisory from 7 PM this evening to 6 AM AKDT Thursday for PKZ858.