textproduct: Fairbanks

SYNOPSIS

Warm weather continues across majority of northern Alaska as southerly flow has set up from a low in the Bering. Portions of the western Seward Peninsula and Bering Strait may continue to see a chance for mixed precipitation through the end of today. Over the next few days, a series of fronts will work their way across the state, bringing chances for isolated showers and afternoon thunderstorms. Most of the precipitation will be confined to the west of the Central Interior as the southerly flow over the Alaska Range will result in downsloping across the Eastern Interior. Some isolated showers may still be possible on the south facing side of elevated terrain. In addition to this, these systems will bring another round of gusty gap winds through the Alaska Range passes. Cold and cloudy conditions are expected to continue over the North Slope through the end of the week as high pressure continues to linger over the Arctic.

KEY WEATHER MESSAGES

Central and Eastern Interior... - Isolated to scattered showers are expected to begin for the Interior today into Tuesday with a non-zero chance of embedded thunderstorms amongst the showers.

- Southerly winds will be diurnally driven throughout the week. Another round of strong gap winds are expected through the Alaska Range passes beginning late tonight, persisting through Tuesday night. Wind gusts through Isabel and Windy Pass are expected to be between 45 and 55 mph. The strongest gusts are expected through Isabel Pass.

- Seasonably normal temperatures are expected to continue across the Interior through much of the week.

West Coast and Western Interior... - Periods of wintry mix are expected to continue through this morning from St. Lawrence Island to the Bering Strait. Light ice accumulations are possible. A Winter Weather Advisory remains in effect through this afternoon.

- Gusty S-SE winds are expected across the West Coast Tuesday afternoon with the shortwave passage.

- Numerous waves of precipitation is expected to move N/NW across the YK-Delta throughout the week. Most of the precipitation will fall as rain, but some patches of wet snow is possible. - Another round of freezing precipitation is possible through the Bering Strait late Tuesday night into Wednesday.

North Slope and Brooks Range.. - Chilly temperatures persist with highs in the 20s and lows in the teens along the North Slope. A gradient of temperatures across the Brooks Range with highs in the 50s to near 60 along the southern slopes and low 40s for the northern slopes.

- Northeast wind speeds are expected remain elevated for the western North Slope through tonight. There may be periods of blowing snow at Point Lay if there remains enough blowable snow to their northeast.

- Showery conditions are expected to continue through Tuesday along the southern portions of the Brooks Range. Little to no precipitation is expected across the North Slope.

- A brief period of increased wind gusts is expected for the NE Arctic Coast Tuesday, bringing the potential for blowing snow.

FORECAST ANALYSIS AND DISCUSSION

Monday through Wednesday. An active pattern continues across much of the state to kick off the week. The bulk of the weather is being driven by a Bering low that has been spinning west of St. Lawrence Island over the last day or so. Meanwhile, an upper-level high has set up over the western Chukchi, along with a ridge strengthening over Canada.

The forecast period starts with a line of showers across the central portion of the West Coast, that will continue to shift to the N/NW throughout today. With cold air advection moving south down the Bering, the western side of this line of showers, extending over the Bering Strait, will see a chance for wintry precipitation through the end of today. Another line of energy will move north across the state today, bringing chances for scattered showers and a slight chance for isolated afternoon thunderstorms. This wave will also work to continue the southerly flow that has been set up across majority of the state. With the southerly flow continuing, the south facing slopes of the Brooks Range are expected to get persistent showers with each of these passing systems. A more pronounced shortwave will follow behind the line of energy, moving over the Seward Peninsula by early Wednesday morning. This will continue to allow the chances for isolated showers and afternoon thunderstorms for the Central Interior and West Coast through the middle portions of the week.

Looking back over the Interior, majority of the area will continue to see the southerly flow set up by the broad troughing across the state. This will keep the area mostly dry, however a shower or two may still be possible at times. With the shortwave moving over the Seward Peninsula, energy from this will extend over the Alaska Range as it shifts north. This will help enhance the gradient and bring the next round for gusty gap winds beginning early Tuesday morning.

A similar pattern is expected to continue toward the later half of the week. By the end of the short-term period, another low will be moving along the northern side of the Aleutians, towards Bristol Bay. This will help to continue the broad troughing across the state and set up another potential for gusty gap winds through the Alaska Range on Thursday.

FIRE WEATHER

A low continues to spin in the Bering Sea with ridging persisting over western Canada. As expected, this pattern will allow for strong southerly flow to continue over the state. As the pressure gradient briefly weakens over the Alaska Range, winds will weaken by the late morning before restrengthening Tuesday morning. This second round of winds through the passes will mimic fairly similar conditions this past weekend with gusts as high as 60 mph possible through Isabel and Windy Pass, and gusts as high as 50 mph through Delta Junction. This cycle of rising and falling winds looks to repeat itself again, with winds weakening Wednesday and strengthening again on Thursday. With min RH values at Delta Junction expected to hover at or near 25% throughout the week, we will be keeping an eye out for potential Red Flag conditions, especially when the winds are strongest Tuesday and Thursday.

Across the rest of Northern Alaska, sunny skies and prolonged daytime heating will keep high temperatures in the 60s, with the warmest temperatures expected on Tuesday in the Yukon Flats. Min RH values will bottom out around 20% across much of the Tanana Valley and Yukon Flats on Tuesday as well, with the western portions of Alaska seeing min RH values between 30 to 40% through the week. Isolated to scattered afternoon rain showers will be possible across the Yukon Delta and eastern Interior this week, but accumulations should remain light. A few of these showers may develop into thunderstorms Monday and Tuesday afternoon, but overall lightning chances should remain low. Winds away from the Alaska Range will generally be out of the south/southeast becoming gusty in the evening and at higher elevations.

HYDROLOGY

Yukon River: The breakup front on the Yukon has passed Grayling. Water remains high on the Yukon upriver from the breakup front due to snowmelt with a Flood Warning remaining in effect for Galena through 10 PM tonight. No significant flooding is expected from this high water, although there may be areas of minor flooding. The latest data from the river gauge at Galena shows the water levels dropping down to 123.7ft and into Action Stage. High water is possible in some villages along the Lower Yukon over the next few days.

Buckland River: Water levels are falling and the river upstream of Buckland is open.

Chena: The Chena River continues to respond to warmer temperatures with higher elevation snowmelt leading to rivers running higher than normal, but likely remaining below action stage.

Additional Information: Visit www.weather.gov/aprfc for the latest hydro information.

Please report observed flooding to local emergency services, law enforcement, or to the National Weather Service when you can do so safely.

EXTENDED FORECAST DAYS 4-7

Thursday through next Sunday. High confidence remains in place through the extended forecast, with a broad upper level trough over the Bering Sea and a ridge of high pressure situated in the NE Pacific. This setup will remain conducive for southerly flow to continue across much of the state, keeping temperatures near normal with highs around the 30s/40s/50s along the coast and 50s/60s in the Interior. The coldest conditions will continue to be across the North Slope north of the Brooks Range where highs in the 20s/30s will be more common with 40s farther south. Long range models remain in good agreement on the location and strength of a surface low around 985 mb in the Southern Bering Sea for Thursday. This system is expected to take a northeast track towards Southwest Alaska and as it does, eject a series of fronts into Northern Alaska that will keep daily scattered showers around heading into the weekend. As this low approaches, a pressure gradient will develop with high pressure over the High Arctic which will lead to gusty winds developing along the West Coast and through Alaska Range Passes. Wind gusts up to around 25-40 mph are expected along the West Coast with gusts up to around 50-65 mph for Alaska Range Passes and at Delta Junction. As the late week Bering Sea low ultimately weakens and dissipates its energy, long range models remain in reasonable agreement on another 985 mb low moving into the Gulf of Alaska this weekend. At this time, this system is expected to stay farther south, with daily scattered shower chances reinforced into early next week by the now broad upper level troughing setup over our region.

Coastal Hazard Potential Days 3 and 4...None

AFG WATCHES/WARNINGS/ADVISORIES

AK...Winter Weather Advisory for AKZ820-821-827. Flood Watch for AKZ829-830. PK...Brisk Wind Advisory for PKZ810-851-856. Small Craft Advisory for PKZ811. Small Craft Advisory for PKZ812. Small Craft Advisory for PKZ816. Small Craft Advisory for PKZ817-854. Brisk Wind Advisory for PKZ857. Small Craft Advisory for PKZ858. Heavy Freezing Spray Warning for PKZ858.