textproduct: Fairbanks

SYNOPSIS

As a series of lows track into Southwest Alaska, rain showers will continue to lift north across Western Alaska and the Interior. As one of these lows track east through Southcentral Tuesday into Wednesday, this will help to reinforce rain chances and support an uptick in westerly winds on the backside of the low. Looking ahead, a strong low remains on track to lift northeast through the Western Bering Sea and Eastern Siberia Wednesday into Thursday, bringing widespread rain and gusty southwest winds into Northern Alaska. These impacts will shift east into the Interior Thursday into Friday, as the Bering Sea low taps into atmospheric river moisture, keeping precipitation chances going through the weekend.

KEY MESSAGES

Central and Eastern Interior...

- Increasing clouds will build in out of the south tonight, as isolated to scattered rain showers lift north over the Alaska Range.

- Winds have already ramped up through the Alaska Range passes out of the south and are expected to remain elevated through Tuesday, peaking Monday night into Tuesday morning with gusts up to around 50 mph.

- Showers will continue for Monday, ahead of steadier and more widespread rain building in Monday night into Tuesday and Wednesday as a low works east through Southcentral.

- Rainfall totals through Tuesday night are expected to be around 0.10 to 0.50 inches, locally higher in the Alaska Range around 0.50 to 1.50 inches where snow levels will be around 7000 to 8000 feet

- On the backside of this midweek system, winds will ramp up out of the west as drier conditions build in. Wind gusts for most will peak Wednesday with gusts up to around 30 to 40 mph.

- Temperatures will trend warmer today into Monday, with highs in the 50s/60s and lows in the 30s/40s.

West Coast and Western Interior...

- A series of lows entering Southwest Alaska and lifting north will bring steadier rain chances to the Yukon Delta and Norton Sound region today, lifting north Monday into Tuesday to encompassing all of Western Alaska.

- Rainfall totals through Tuesday night are expected to be around 0.10 to 0.50 inches, with drier conditions out at St. Lawrence Island.

- Southwest winds will pick up on Wednesday ahead of a strong low and atmospheric river moving into Western Alaska late Wednesday into Thursday and Friday. This system will bring widespread rain, gusty winds, and onshore flow, with the potential for high surf and minor coastal flooding. Stay tuned for additional updates.

- Temperatures will hold steady through midweek, with highs in the 40s/50s to low 60s with lows in the 30s/40s.

North Slope and Brooks Range...

- Widespread low stratus and areas of fog persist.

- Conditions will trend drier today into early Monday outside of very isolated showers, with another front lifting north throughout the day Monday into the Brooks Range with rain showers, especially for the NW Arctic Coast.

- Rainfall totals through Tuesday night are expected to be around 0.10 to 0.50 inches in the Central/Western Brooks Range and NW Arctic Coast south of Point Hope.

- Temperatures will hold steady or see a warming trend through midweek with highs in the 40s/50s and lows in the 30s/40s, colder across higher elevations of the Brooks Range.

- As a strong low tracks northeast through the Bering Sea with atmospheric river moisture Wednesday into Thursday, widespread rain and gusty winds will build into far Northern Alaska Thursday into Friday.

- With onshore flow across the NW Arctic Coast, there will be the potential for high surf and minor coastal flooding. Stay tuned for additional updates.

SHORT TERM

Today through Tuesday Night. Early afternoon satellite imagery shows a triple point low centered in the Bering Sea, with one low moving into Southwest Alaska and the other two situated out over the Central Bering. This first low is lifting a front into Western Alaska currently with scattered rain showers, which will extend into the Interior tonight into Monday as moisture works over the Alaska Range. Southerly downsloping flow over the Southern Interior will work to limit moisture transport north, with only very light rain amounts expected in the Central and Eastern Interior during this timeframe. That pair of lows out in the Bering will combine into one circulation on Monday, and track east through Southcentral Monday night into Tuesday and Wednesday. This system will work to reinforce these rain chances through midweek, as steadier rain over Western Alaska shifts into the Interior. Associated with these systems, winds have already begun to pick up through the Alaska Range passes. These winds are expected to remain elevated through Tuesday, peaking Monday night into Tuesday morning with gusts up to around 45 to 50 mph. Have held off on any Wind Advisory issuance at this time given the more marginal winds. Rainfall totals regionwide through Tuesday night are expected to be around 0.10 to 0.50 inches south of and including the Brooks Range. Locally higher precipitation totals are expected in the Alaska Range where efficient southerly upslope flow will favor totals closer to 0.50 to 1.50 inches, with snow levels around 7000 to 8000 feet. West to southwest winds will ramp up Tuesday night into Wednesday as this system to our south tracks east, with more details on that below.

LONG TERM

Wednesday through next Sunday. At the start of the extended period Wednesday morning, two upper- level shortwaves will be producing generally unsettled weather across Alaska. The first shortwave should be on its way out over the Panhandle. This shortwave came from the Pacific and will therefore bring a decent streak rain to Southern Alaska. The second shortwave will likely be just arriving from the west after tracking over Siberia. As a result, showers will be lighter over northern Alaska. Both of these features will work in tandem with high pressure building over southeast Alaska to produce particularly gusty winds across Interior Alaska through the day on Wednesday. This stretch of active weather will serve as a precursor to another, more significant low coming in from the northwest Pacific later Wednesday evening.

Models depict a swath of moisture originating from near Japan being pulled northeast by that low, directly into Western Alaska. Precipitable water within that swath is projected to range between an inch to an inch and a half. The heaviest rain is expected to impact St Lawrence Island, the Southern Seward Peninsula, and the Brooks Range as far east as Coldfoot. The rest of the Western Interior will see heavy to moderate rain through Friday. Rain amounts gradually decrease farther into the Interior.

In addition to the heavy rain, southwest winds in the Bering and along the West Coast will strengthen, peaking on Thursday with gusts expected to reach 50 to 60 mph. before they begin to subside as the low moves away on Friday. Similarly with the rain, winds will be strong in the Interior, but to a lesser extent. We are monitoring the strength and direction of these winds and their impact on water levels along the West Coast. Depending on the direction and strength of the winds, and the length of the fetch, these winds will result in high surf, and possibly minor coastal flooding for a some locations. We will update you as confidence improves.

Periods of rain and breezy conditions will last through the weekend, with the initial system being reinforced by another shortwave moving up through the latter half of the weekend.

COASTAL HAZARD POTENTIAL

Confidence is growing in a respectable strength 975-985 mb system which will move over NE Siberia Thursday and Friday. Strong SW flow near the surface of 25-30kt sustained could bring elevated chances of high surf, and potentially even minor coastal flooding to parts of the West Coast. Currently anticipate that the best chances for elevated surge levels will be around Norton Sound, Bering Strait, and NW Arctic Coast, where the strongest winds will be onshore for at least 18 to 24 hours.

FIRE WEATHER

A brief lull in rainfall across the Interior will continue through tonight ahead of the next system. Highs in the low to mid 60s are expected by this evening in Central and Eastern Interior valleys, with min RH values in the southeastern Interior ranging from the low 40s to the low 50s %. Similar conditions will persist in these areas into Monday, with increasing southerly winds through the Alaska Range passes. Farther west, min RH values will remain well above critical thresholds on both days, with highs generally in the mid to upper 50s, with rain and westerly winds overspreading much of Western Alaska by Tuesday morning as a low pressure system approaches the area. This rain and increasingly gusty westerly winds will expand across much of the remainder of Northern Alaska by Tuesday afternoon, including some recently dry portions of the Upper Tanana Valley, where wetting rains will be more likely than not by Wednesday evening. Some of these areas as well as the Fortymile Country and eastern Alaska Range could also see isolated thunderstorms with weak instability in the area and a north-moving wave moving across the area. Additional widespread rainfall will remain possible across most of Northern Alaska late in the week as another system approaches, although the Upper Tanana Valley will likely remain drier with this next round of rainfall.

HYDROLOGY

Rainfall totals through the first half of the week will be low enough that flooding concerns are not anticipated. Atmospheric river moisture will build in to finish out the week from the Bering Sea, which will continue to be monitored.

AFG WATCHES/WARNINGS/ADVISORIES

AK...None. MARINE...None.