textproduct: Fairbanks

SYNOPSIS

Widespread upper level ridging is expected for much of Northern Alaska, driving high temperatures in the Interior and West Coast into the low to mid 70s Wednesday and Thursday. An Arctic low will begin to dig down south by Wednesday night into Thursday, strengthening north/northwesterly winds over the Brooks Range and Kotzebue Sound through Friday night. This low is also expected to bring westerly flow and moisture to the region, influencing cooler and wetter conditions. Scattered showers, rain for the Interior and snow for the North Slope, are expected through the weekend and early next week.

KEY WEATHER MESSAGES

Central and Eastern Interior...

- A pattern change will allow for warmer temperatures reaching the low to mid 70s over most of the Interior valleys beginning today and continuing into Thursday.

- Scattered showers are possible for the Alaska Range, Eastern Interior, and Northern Interior through the weekend and early next week.

West Coast and Western Interior...

- Warmer temperatures with highs in the low to mid 70s through Thursday.

- Mostly clear and dry conditions persist for inland areas through Thursday until clouds build in later this week.

- Diurnal fog and low clouds for the western coast near Norton Sound and Kotzebue Sound may persist through tonight.

- Strong west to northwest gusts are likely to pick up this morning over Kotzebue Sound through Friday night with gusts up to 30 mph likely.

North Slope and Brooks Range..

- Below average conditions are expected to persist with temperatures mostly between 30 and 40 degrees through Friday.

- More snow moves into the northern Brooks Range and North Slope today, with some rain mixing in during the daytime hours. Accumulations around an inch with higher amounts at elevation in the Brooks Range.

- Strong north/northwest gusts are likely to pick up this morning over the Brooks Range through Friday night with gusts up to 30 mph likely.

FORECAST ANALYSIS AND DISCUSSION

Wednesday through Friday.

Widespread upper level ridging is expected for much of Northern Alaska through Thursday, influencing warmer and drier conditions. Many areas within the Interior and West Coast are likely to see high temperatures up to the low to mid 70s for Wednesday and potentially Thursday. By Thursday afternoon, an Arctic low will begin digging down over the North Slope, bringing the first chances for scattered rain and snow showers of the upcoming weekend. Cooler temperatures and westerly flow associated with this low are expected to bring high temperatures back down into the 60 degree range for most of the Interior and West Coast. Wetter conditions are also likely for this weekend, with scattered rain showers possible for the Alaska Range, Northern Interior, and Eastern Interior through the weekend.

As the Arctic low shifts southward starting late Wednesday into Thursday, a strong pressure gradient forms over the Kotzebue Sound and Brooks Range and lasts through Friday night. As a result, strong northwesterly winds ramp up through these areas, reaching 30 mph gusts at times.

FIRE WEATHER

Upper-level ridging is expected to persist through much of the rest of the week, leading to a decrease in shower and thunderstorm activity. Light, isolated showers are possible, but chances of wetting rain and thunderstorms remain unlikely. High temperatures are expected to remain in the 60s and 70s everywhere except the North Slope where areas will remain in the 20s and 30s. Minimum relative humidities are expected to generally be in the 30% range, except the Tanana Valley, Fortymile Country, and the Yukon Flats where 20% is possible. Winds are expected to be generally light, but may increase near the Seward Peninsula and Brooks Range Wednesday night into Thursday. A pattern shift is expected towards the end of the week and into the weekend as upper-level troughing builds into the state from the north, leading to the possibility of isolated showers and thunderstorms returning as shortwaves move into northern Alaska.

HYDROLOGY

No changes from the previous hydro forecast discussion.

Sagavanirktok River: Some overflowing is occurring; however, breakup along the Sag River has not begun yet. Today and Wednesday look to be the warmest days with highs in the 30s to near 40 along the coast and low 50s towards the northern Brooks Range. Temperatures will then dip back down later in the week to below normal, around the low 30s for a high near the coast and the mid to upper 30s for the northern Brooks Range. Near the Sag River source on the north Brooks Range, high temperatures could reach the mid 50s through Wednesday, with snow levels reaching upwards of 4000 ft. Again, temperatures look to cool going into the late week but continue to be above freezing.

EXTENDED FORECAST DAYS 4-7

For Saturday through next Tuesday.

At the start of the extended forecast period Saturday, the overall pattern will be dominated by broad troughing centered on a large upper level low over the high Arctic. Temperatures cool under this pattern with highs falling back into the low to mid 60s in the Interior and below freezing along the Arctic Coast. Afternoon showers and the occasional extremely isolated afternoon thunderstorm are possible each day under this pattern. Heavier showers are only expected when stronger shortwaves rotate through the pattern across the state. When these cross the region, stronger northwesterly winds are expected along the Chukchi Sea Coast and westerly winds across the Arctic Coast are expected as well as heavier showers. There is still some uncertainty regarding the exact timing and strength of these shortwave features, but there is a good chance that one will cross the region early next week bringing back more widespread showers.

Coastal Hazard Potential Days 3 and 4...None

AFG WATCHES/WARNINGS/ADVISORIES

AK...None. PK...None.