Fairbanks North Star Borough, AK Weather

Key messages

Central and Eastern Interior:

- Widespread precipitation moves in from west to east on Monday, with rain in the valleys and snow above 2000 feet. Rainfall accumulations of 0.10-0.30" is expected with lighter accumulations east of Fairbanks. Snow amounts generally around 2-4" is likely across the highway summits, but only around a T-1" possible the valleys.

- Drier conditions are expected going into Tuesday, with clearing skies giving way to cooler overnight temperatures in the low/mid 20s Tuesday and Wednesday night. Potentially slick travel conditions may result where standing water or wet road surfaces refreeze overnight.

- A strong, organized, and wet front moves in from west to east Wednesday into Thursday, bringing back rain and high elevation snow chances to the Interior. Additionally, gusty southerly winds strengthen through the Alaska Range Passes with gusts up to 65 mph possible.

- Remnants of Typhoon Champi moves inland Thursday, pushing an additional wave of precipitation and gusty winds into the Interior Friday through Saturday. More details on this storm to come soon.

- High temperatures remain in the low/mid 30s through the end of the week with lows in the mid/upper 20s. A gradually decline of temperatures is likely going into the weekend.

West Coast and Western Interior:

- Widespread rain, gusty winds, and high surf continues to impact the West Coast today with an additional 0.10-0.25" expected through Monday night.

- As another low moves into the Bering Sea and tracks north into the Gulf of Anadyr Tuesday into Wednesday, rain and high elevation snow showers impact portions of the West Coast and Western Brooks Range. Highest rainfall accumulations will be around Nome with an additional 0.25-0.50" expected through Tuesday night.

- By Wednesday, a front connected to the preceding system taps into an atmospheric river and drapes itself over the West Coast. This front/AR works to support a continuation of moderate/heavy rainfall across Western Alaska as it gradually moves east through Thursday. Rainfall accumulations of 0.50-1.50" are possible across the West Coast with up to 0.50 possible in the Western Interior.

- Remnants of Typhoon Champi move into the Bering Sea Thursday through Friday, reinforcing widespread moderate/heavy precipitation chances, gusty winds, and potentially some coastal flooding/high surf conditions across Western Alaska. More details on this storm to come soon.

- High temperatures will remain in the upper 30s/low 40s, with overnight lows in the 30s.

North Slope and Brooks Range:

- Snow gradually tapers off through Monday night across the Brooks Range with additional accumulations around 3-5" north of Coldfoot and 1-3" near Anaktuvuk Pass.

- Drier conditions are expected Tuesday through Wednesday afternoon east of Anaktuvuk Pass while the Western Brooks Range continues to see persistent snow showers through midweek. Periods of blowing snow may develop at times through Wednesday as winds gust to around 35 to 50 mph.

- Fairly calm and benign weather persists along the rest of North Slope thanks to predominantly southerly flow. Expect highs in the low/mid 30s and lows in the mid/upper 20s through midweek.

Synopsis

Widespread rain and high elevation snow showers continue to build into the Interior from west to east this morning as a now weakening Bering Sea low moves inland over the West Coast. As this system moves east, widespread rain/snow showers, gusty winds, and elevated water levels will continue to impact the the West Coast, with several inches of accumulating snow expected in the Brooks Range. By Tuesday, a period of drier weather settles in for the Interior and eastern half of the North Slope. However by Wednesday, another round of rain/snow, gusty winds, and elevated water levels impact the West Coast due to a strong, moist low in the Gulf of Anadyr. A front associated with this low moves east through the state on Thursday and supports moderate/heavy rains across Northern Alaska. Towards the end of the week, remnants of Typhoon Champi move into the Bering Sea with specific impacts from this storm are still uncertain right now. Stay tuned for more details.

Short term

The forecast remains on track as active weather prevails across Northern Alaska. We start off by examining a now weakening low moving east across the state, gradually building in widespread rain/snow showers over the Interior. Through the day, we expect to see snow levels gradually rise to around 2000 feet, keeping rain the predominant precipitation type within the valleys. Rainfall accumulations will be highest from Fairbanks west, with very light accumulations expected farther east. At elevation, light to moderate snowfall is expected along the highway summits, but impacts from this look to remain minimal. However, because this storm brings quite a bit of warm air and moisture with it, rain on top of snow may lead to slushy and wet travel conditions. Along the West Coast, conditions gradually improve through the day, with some lingering rain/snow showers in the Western Interior and Brooks Range.

As we look towards Tuesday, rain/snow showers will have largely moved out of the Interior as high pressure strengthens in the Gulf of Alaska. Simultaneously, another low in the Bering Sea makes its way up north into the Gulf of Anadyr, working to reinforce strong southwesterly flow over the West Coast. Models are in pretty good agreement with the strength of this low hovering somewhere around 500 dam at 500 mb, which is fairly strong. However, due to its far west track, its impacts will be limited to just the West Coast and Western Brooks Range through Wednesday. As a result, we see a continuation of rain, high elevation snow, gusty winds, and elevated water levels all along the coast from Hooper Bay north to Kivalina. Although southwesterly flow tends to be a bit concerning for the West Coast during this time of year, we thankfully see within the latest PETSS guidance that water levels should only remain marginally higher than normal with most communities seeing water levels anywhere from 2 to 4 feet above the normal high tide. However, because this is the third storm of note within the last week or so, beach erosion continues to be a point of concern. High Surf Advisories remain in effect in these regions through early Wednesday morning.

Once this storm moves farther north into the Chukchi Sea through Wednesday, it leaves behind a very well organized front that taps into an abundance of moisture via an atmospheric river. This front drapes over the West Coast by Wednesday evening and gradually pushes east across the state into Thursday morning. As a result, widespread rain showers build into the Interior once again from west to east, with the highest accumulations expected across the West Coast and Western Interior. A few embedded snow showers are possible with this system, but will mainly be confined to the Western Brooks Range. Outside of precipitation, other impacts from this system include strengthening southerly gap winds through the Alaska Range Passes. Gusts may reach as high as 65 mph at times through Wednesday evening. These winds are expected to briefly subside going into Thursday morning but quickly ramp up again Thursday afternoon as remnants of Typhoon Champi move into the Bering Sea and reinforce strong southerly flow through the passes. There is still quite of bit of uncertainty regarding the extent of impacts from this storm, but more on this will be discussed in the "Long Term Discussion".

Long term

At the start of the extended forecast period, Thursday, what was the Gulf of Anadyr storm will have moved across Siberia and into the Arctic Ocean west of the date line. Another storm system has entered the southwestern Bering Sea in its wake and is on a course for the West Coast. This next storm system is a low that, before entering the Bering Sea, combined with the remnants of Typhoon Champi. This storm is therefore fairly strong, with a peak low pressure in the 960 to 970 millibar range and very wet.

Forecast confidence has grown regarding the track this storm will take towards the West Coast Thursday into Friday. Previous model runs suggested a range of tracks potentially making landfall anywhere from the Seward Peninsula to the northern portions of Bristol Bay, but recent model trends have begun to concentrate potential tracks near Nunivak Island. A track in this location would favor easterly, offshore, flow across most of the West Coast from Hooper Bay north which would limit coastal flooding potential for much of the region. Higher than normal water levels would still be expected for many areas due to storm surge, but less favorable winds would limit coastal impacts. The storm remains very wet with widespread moderate to heavy precipitation expected across the Western portions of the state Thursday which would be able to move inland Friday and Saturday. Most of this precipitation would be rain in the valleys, with snow expected along Interior summits and in the larger mountain ranges. There is still some uncertainty with this storm, but forecast details are beginning to become clearer. We will continue to monitor this storm and provide updates as the forecast certainty continues to increase.

Coastal hazard potential

A series of storm systems continue to move through the Bering Sea this week. The current storm system is the second in this series and, as of early Monday morning, continues to move northeast through the Seward Peninsula. This low rapidly weakens through Monday, but the next storm system enters the Western Bering Sea Monday morning as well. This next storm is significantly stronger than the previous two and is expected to be the strongest in this series of storms. Thankfully its expected track is almost due north from the Western Aleutians towards the westernmost edge of the Gulf of Anadyr. Due to this track, coastal impacts will be significantly limited despite the size and strength of the storm. It however will keep water levels above normal. High Surf Advisories are in effect for the entire West Coast from Hooper Bay to Kivalina. Several days of higher than normal water levels across most of the coast enhances the risk of beach and coastal erosion.

Water levels are expected to have a brief window to decrease late Wednesday into Thursday ahead of yet another large low pressure system that moves through the Bering Sea. This storm system contains the remnants of Typhoon Champi causing it to be fairly strong, peaking in the 960 to 970 millibar range, and very wet. Confidence is increasing in the track of this storm as it moves from the southwestern Bering Sea towards the West Coast Thursday. Current forecasts trends are concentrating possible storm tracks near Nunivak Island. A track south of the Norton Sound would limit the potential for coastal hazards for areas north of Hooper Bay due to mostly easterly, offshore, winds. The storm surge would still keep water levels above normal though with beach and shore erosion remaining a likely threat. It is still too early to give any specific expected details regarding potential impacts from this storm system, but forecast trends are beginning to favor a more southerly track which would be less impactful for the Norton Sound Coast. We will continue to monitor this storm and update the forecast as confidence continues to increase.

Hydrology

Several very wet storm systems are expected to move across Alaska this week. The heaviest precipitation from these storm systems is currently expected across the higher elevation areas of the West Coast and Western Interior, especially along the Southern Seward Peninsula and 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. Additional precipitation totals across much of Western Alaska will be around 1 to 3 inches for most locations, with south facing slopes potentially seeing some locally higher totals. There is a chance that there could be enough rainfall induced snowmelt to bring some minor flooding concerns to rivers and streams in the immediate vicinity of those higher terrain areas of Western Alaska. This chance is most likely in those portions of Western Alaska that could see those locally higher precipitation totals where nearby rivers and streams are already relatively high.

Watches, warnings and advisories

AK: Winter Weather Advisory until 10 PM AKDT this evening for AKZ809-837-839>845. Winter Storm Warning until 10 PM AKDT this evening for AKZ812- 831. High Surf Advisory until 4 AM AKDT Wednesday for AKZ815-817- 818-820>822-824-825. High Wind Warning from 4 PM this afternoon to 4 PM AKDT Tuesday for AKZ820-821-827. Winter Weather Advisory until 4 PM AKDT Tuesday for AKZ832-834- 835-838. MARINE: Gale Warning until 7 AM AKDT this morning for PKZ801-802. Small Craft Advisory until 1 PM AKDT this afternoon for PKZ801- 802-805-850-853. Small Craft Advisory from 4 PM this afternoon to 6 PM AKDT this evening for PKZ801-802-816-850. Small Craft Advisory until 4 PM AKDT this afternoon for PKZ803- 804-852. Small Craft Advisory until 10 AM AKDT this morning for PKZ816- 851. Small Craft Advisory from 1 PM this afternoon to 6 PM AKDT this evening for PKZ851.