textproduct: Fairbanks

KEY MESSAGES

Central and Eastern Interior...

- Following light rain/snow showers today into tonight, widespread precipitation and breezy winds will build in west to east on Monday. With warming temperatures, rising snow levels will lead to a transition over to mostly rain in the valleys throughout the daytime hours.

- Precipitation amounts through Monday night are expected to be around 0.10-0.30" for most, with a T-0.10" east of FNSB. Up to 2-4" of snow will be possible across higher elevation highway summits, with lighter snow amounts in the valleys. Wind gusts will peak around 20 to 35 mph out of the southwest regionwide.

- Dry conditions will return west to east Monday night into Tuesday, as clearer skies Tuesday night into Wednesday give way to overnight lows in the teens and 20s. Any wet ground surfaces will likely refreeze, creating potential slick travel conditions.

- High pressure will keep conditions dry for Tuesday and Wednesday, with a front working west to east Wednesday night into Thursday bringing the return of rain/snow showers. Southerly gap winds will ramp up Tuesday night into Wednesday through the Alaska Range passes, with gusts up to 65 mph possible.

- Remnants of Typhoon Champi will move into Western Alaska Thursday into Friday, with rain/snow showers building into the Interior Thursday night into Friday and Saturday. Southerly gap winds will increase yet again during this timeframe, with gusts over 70 mph possible.

- Highs in the 20s/30s to low 40s will persist through Friday, with lows in the teens/20s to low 30s as coldest locations remain farther east.

West Coast and Western Interior...

- As a 980 mb low in the Bering Sea continues to track northeast towards the Kotzebue Sound today into Monday, widespread rain, high elevation snow, high surf, and wind gusts of 30 to 55 mph will continue to build into Western Alaska. Up to around 0.75" of rain is expected, with moderate to heavy rain at times.

- Following this first system, a second 970 mb low will track northeast through Eastern Siberia Tuesday into Wednesday, driving another front into Western Alaska widespread rain, high elevation snow, high surf, and wind gusts of 40 to 60 mph primarily along the West Coast. - As atmospheric river moisture brought in by the second low continues to build into Western Alaska Wednesday, a shortwave trough and or a weak closed low lifting northeast will help keep steady rain chances going as the front gradually shifts inland. Rainfall with this second and third system will be around 0.50-1.50" along much of the coast, and 0.25-0.50" in the Western Interior.

- Attention then quickly turns to remnants of Typhoon Champi which will enter the Bering Sea on Wednesday, ultimately moving into Western Alaska Thursday into Friday. This system is expected to be around 965 mb in the Central Bering Sea and gradually weaken as it moves inland.

- Exact forecast details regarding this strong storm later in the week will come into focus over the coming days, with the potential for strong winds, heavy precipitation, and coastal flooding/high surf. Stay tuned for updates.

- High temperatures will hold steady in the upper 30s to mid 40s, with overnight lows in the 30s to low 40s.

North Slope and Brooks Range...

- Moderate snow will continue in the Brooks Range tonight into Monday, with drier conditions returning Monday night into Tuesday. Additional snow amounts through Monday will be around 3-6" from Galbraith to Coldfoot with higher amounts above pass level, while Anaktuvuk Pass is expected to see another 1-3".

- Winds gusts up to around 30 to 40 mph will persist over Atigun and Anaktuvuk Passes, which could lead to periods of blowing snow at times with localized blizzard conditions possible.

- Two successive Bering Sea lows lift north through Tuesday, bringing additional snow, gusty winds, and elevated water levels to parts of the Chukchi Sea coast and Western Brooks Range. A High Wind Watch remains in effect for the Western Arctic Coast around the Lisburne Peninsula for wind gusts up to 60 mph Monday night into Tuesday.

- Elsewhere across the North Slope, a mix of sun and clouds will prevail as winds remain out of the south and conditions remain predominantly dry.

SYNOPSIS

An active weather pattern will continue across Northern Alaska into next week, as a ridge of high pressure in the Northeast Pacific maintains a favorable storm track into Western Alaska. Rain/snow chances will continue across the Western Interior today with steadier snow in the Brooks Range, as more isolated showers persist along the West Coast. A pair of strong Bering Sea lows will lift northeast through the Bering Strait into the Chukchi Sea Sunday into Monday and again Monday into Tuesday, bringing additional rounds of rain/snow, gusty winds, and high surf to Western Alaska. Across the Interior, this system will bring widespread rain/snow and gusty winds. Following yet another system on Wednesday primarily impacting the West Coast, we are closely monitoring remnants of Typhoon Champi as it makes its way into the Bering Sea on Wednesday, with impacts reaching Western Alaska Thursday into Friday.

SHORT TERM

Today through Tuesday Night. Scattered rain/snow showers continue this morning across Northern Alaska as a decaying low moves north through the Chukchi Sea. These showers will continue to move east and impact portions of the West Coast and Interior through Sunday, with pockets of freezing rain possible in the valleys of the Central Interior during the afternoon. Areas which experience strong upslope flow due to southwesterly flow aloft will see snowfall accumulations of several inches, especially within the Brooks Range, Alaska Range, and Koyukuk Valley. Periods of blowing snow may develop where gusty winds coincide.

By Sunday night, a second Bering Sea low follows closely behind the heels of its predecessor and tracks northeast towards Norton Sound. As this system moves inland, another round of rain/snow is expected along the West Coast in addition to elevated water levels. These higher water levels prompted the issuance of High Surf Advisories along the coast from Hooper Bay north to Kivalina. Shoreline erosion could occur. Elsewhere, as this system pushes farther east, an additional wave of rain/snow showers moves into the Interior. Because this second system brings quite a bit of warm air and moisture with it, temperatures climb into the upper 30s/low 40s on Monday, keeping rain the predominate precipitation type below 2000 feet. Accumulations will be a tad higher than with the preceding storm, but overall remain fairly light around 0.30" in the valleys and 2-4" of snow at higher elevations through Monday night. Across the Western/Central Brooks Range, upslope flow will support additional snowfall accumulations of 3-6" along the Dalton, with locally higher amounts near 12" possible above pass level.

Looking towards Tuesday, a third Bering Sea low tracks north into the Gulf of Anadyr simultaneously as high pressure reestablishes itself in the Gulf of Alaska. This helps to reinforce southwesterly flow over the state and allows for yet another round of rain/snow, gusty winds, and coastal flooding to impact Western Alaska. With this, High Wind Watches were issued along the Chukchi Sea coasts through late Tuesday night. Because this low's track stays farther offshore than the previous two systems, impacts from this storm remain confined to the West Coast and Western Brooks Range, giving the Interior and eastern half of the North Slope a brief break from active weather. By Tuesday night, this low will have moved into the Chukchi Sea and drape a well organized front across the state. This system will be tapping into atmospheric river moisture, which will keep precipitation chances going into Wednesday. This front will move northeast across the state Wednesday through Thursday, briefly cooling temperatures down a bit ahead of a fourth system that looks to move into the Bering Sea Thursday into Friday. More on this system in the Long Term Discussion below.

LONG TERM

Wednesday through next Sunday. At the start of the extended forecast period, Wednesday, the third storm in our series of storms will have cross eastern Siberia into the Arctic Ocean west of the date line. An atmospheric river connected to that low that was pulling a large amount of moisture into Western Alaska separates from the low, allowing what remains of that moisture to shift inland. Additional rain and snow is expected across the Interior Wednesday into Thursday. Higher pressure over Canada and the Eastern Interior is weakened somewhat by this push of moisture. The fourth storm in our forecast enters the southwestern Bering Sea Wednesday and pushes east towards the West Coast through Thursday. This fourth storm is expected to contain remnants of Typhoon Champi and thus is expected to be fairly strong, around 960- 970 millibars in strength as it approaches the West Coast, and very wet.

The exact position of the storm as it makes landfall is still uncertain. The majority of model ensemble members suggest that the storm will take a path east into Western Alaska, making landfall near the YK Delta. Most of the 00Z run GEFS and Canadian ensemble members support a more southerly track landing near Nunivak Island. The 00Z run European ensemble is far less confident than the GFS and Canadian models with members stretching across much of the Eastern Bering Sea with members as far south as Bristol Bay and as far north as the Seward Peninsula. The location of this storm center as it approaches the West Coast will have very large impacts on the coastal waters forecast and coastal flooding potential. More southerly tracks will cause most of the strongest winds along the Norton Sound, Chukchi Sea, and Bering Strait Coasts to be more easterly, significantly limiting flooding potential for areas along the coast from Hooper Bay north. More northerly tracks could bring coastal flooding and erosion impacts back to the West Coast.

Regardless of track, an immense amount of moisture is expected with this system. Most of the West Coast and Western Interior will see another round of heavy precipitation, mostly rain in the valleys with snow possible at higher elevations. Most models have this precipitation pushing well into the Central Interior and even into portions of the Eastern Interior Friday into Saturday. Gusty easterly winds are expected as the storm pushes against higher pressure to the east. The amount of moisture will help keep temperatures above normal moving into the weekend.

COASTAL HAZARD POTENTIAL

A series of storm systems continues to move through the Bering Sea and impact the West Coast. Storm impacts are expected to continue in some form through the end of the week. There are four main storms to keep track of. The first is in the Chukchi Sea and continues to exit the region to the north. It previously brought increased water levels to most of the West Coast. Water levels began declining from their peak Saturday. High Surf Advisories remain in effect for the West Coast from Hooper Bay to Kivalina.

The second follows the first Sunday afternoon through Monday. It's a weaker system than the first and follows a slightly more easterly path. This storm is expected to keep water levels slightly elevated across the West Coast with widespread high surf conditions expected. A major component of the impacts from this storm is that it follows the first closely enough that water levels will not fully receed. Multiple high tide cycles with high surf conditions could lead to extensive coastal erosion.

The third storm is quite a bit strong, but tracks much farther west of the first two storms. It moves through the Western Bering Sea Monday into Tuesday almost directly north from the Western Aleutians into Eastern Siberia. An atmospheric river attached to this storm system spins east of it over the West Coast, but the primary coastal impacts will be a slight increase in water levels over the previous high surf water levels. This increase in water levels could cause additional coastal flood impacts, although high surf is still expected to be the majority impact for most of the coast. High Surf Advisories have been extended for the West Coast to account for continued higher than normal water levels that are expected.

The forth storm is potentially the most impactful. The low pressure system in question is expected to enter the southwestern Bering Sea Wednesday and push towards the West Coast through Thursday. This storm system is expected to contain remnants of Typhoon Champi which will keep it fairly strong (in the 960-970 millibar range) and very wet. There is still some uncertainty regarding the exact track of this storm system which was detailed in the long term forecast section. Coastal impacts will largely depend on its exact track as it makes landfall into Western Alaska. We will continue to monitor this storm closely and update the forecast as the storm track becomes more certain.

HYDROLOGY

As a series of strong storms in the Bering Sea continue to support rain/snow into next week, we will be closely tracking atmospheric river moisture as it builds into Northern Alaska. The track and timing of the heaviest rain/snow will continue to be monitored over the coming days, with heaviest totals expected across higher elevations of the West Coast, Southern Seward Peninsula, and in the Western/Central Brooks Range. At this time, we are not anticipating any rain or snowmelt related flooding, but we will continue to monitor should the situation change. The main factor will be if we are able to see rainfall induced snowmelt, which could lead to minor flooding concerns immediately closest to the higher terrain in nearby rivers and streams. Additional precipitation totals across much of Western Alaska will be around 1 to 3 inches for most, with locally higher totals in southerly upslope favored regions.

AFG WATCHES/WARNINGS/ADVISORIES

AK...High Wind Watch from Monday evening through Tuesday evening for AKZ801. Winter Weather Advisory until 10 PM AKDT Monday for AKZ809-837- 839>844. Winter Storm Warning until 10 PM AKDT Monday for AKZ812-831. High Surf Advisory until 4 AM AKDT Wednesday for AKZ815-817- 818-820>822-824-825. High Wind Watch from Monday afternoon through Tuesday afternoon for AKZ820-821-827. Wind Advisory from 7 PM this evening to 10 AM AKDT Monday for AKZ830-852. Winter Weather Advisory from 10 PM this evening to 4 PM AKDT Tuesday for AKZ832-834-835-838. Winter Weather Advisory until 4 PM AKDT Monday for AKZ845. MARINE...Small Craft Advisory until 1 AM AKDT Monday for PKZ801-854-858. Small Craft Advisory from 4 AM to 1 PM AKDT Monday for PKZ801. Small Craft Advisory from 4 PM to 6 PM AKDT Monday for PKZ801- 802-816-850. Gale Warning until 7 AM AKDT Monday for PKZ801. Small Craft Advisory until 1 PM AKDT Monday for PKZ802-805-850- 853. Gale Warning from 1 AM to 7 AM AKDT Monday for PKZ802. Small Craft Advisory until 4 PM AKDT Monday for PKZ803-804-852. Small Craft Advisory until 4 AM AKDT Monday for PKZ806-809-810. Small Craft Advisory until 4 PM AKDT this afternoon for PKZ807. Small Craft Advisory from 10 PM this evening to 4 AM AKDT Monday for PKZ807-856. Small Craft Advisory from 7 PM this evening to 4 AM AKDT Monday for PKZ808. Brisk Wind Advisory from 1 AM to 4 AM AKDT Monday for PKZ809. Small Craft Advisory until 10 PM AKDT this evening for PKZ811- 857. Small Craft Advisory until 1 AM AKDT Monday for PKZ812-817. Small Craft Advisory until 10 AM AKDT Monday for PKZ816. Gale Warning until 7 PM AKDT this evening for PKZ850. Gale Warning from 1 AM to 4 AM AKDT Monday for PKZ850. Small Craft Advisory until 10 AM AKDT Monday for PKZ851. Small Craft Advisory from 1 PM to 6 PM AKDT Monday for PKZ851. Small Craft Advisory until 4 AM AKDT Monday for PKZ855. Small Craft Advisory until 7 PM AKDT this evening for PKZ856.