textproduct: Fairbanks

SYNOPSIS

An arctic low is quickly moving southeast through the Chuckchi and Bering Sea this morning towards the Gulf. This will provide some energy that will help to produce isolated to scattered showers and thunderstorms today across the Eastern Interior, Norton Sound Coastline, and the Southern Interior. Low pressure will be the dominant feature for the next several days keeping temperatures moderated and bringing daily precipitation chances across the Interior. Early next week there are signals for high pressure to arrive, with that, warmer and drier conditions are possible.

KEY WEATHER MESSAGES

Central and Eastern Interior... - Isolated to scattered showers are possible over the next couple of day. These will be accompanied with a chance to see an isolated thunderstorm today. Most of the storms will be relegated to the higher terrain today, but could move into the valleys.

- Temperatures will struggle to reach seasonable normal with the Tanana Valley and Yukon Flats barely making it into the 70s, and everywhere else in the Eastern Interior remaining in the 60s.

West Coast and Western Interior... - Gusty northerly winds will strengthen today across the coastline with the strongest winds in the Bering Strait. The Bering Strait could see wind gusts up to 40 mph through Friday night.

- A quick moving front will bring rain chances to the Seward Peninsula, St. Lawrence Island, and Y-K Delta today. The Eastern Norton Sound coastline and Lower Yukon could see an isolated thunderstorm as the front moves across.

- Temperatures will remain in the 50s/60s today across most of the region, and will see a slight warmup starting Friday as the arctic air moves out of the region.

North Slope and Brooks Range.. - Rain and snow will continue across the western Brooks Range and western North Slope today. At Utqiagvik this morning we have seen a glaze of ice develop from a period of Freezing Rain. After 7 am the threat of freezing rain rapidly diminishes.

- Temperatures will remain fairly static over the next couple of days with 30s/40s along the coast and upper 50s/60s on the plains.

- Later this afternoon northerly winds will begin to strengthen across the Brooks Range. We could see 20 to 30 mph winds across the Range, with the strongest winds on Friday. Gusty winds will stick around until Saturday.

FORECAST ANALYSIS AND DISCUSSION

A vorticity maxima that was at the base of an arctic trough had finally wrapped up on itself, and it is now closing off as it races southeast towards the Gulf from Eastern Siberia. This low will be weak with a surface pressure around 1010 mb, and is only just one of a few weak lows that are influencing mainland Alaska. These lows will keep cooler and rainier weather around for most of Northern Alaska. A low that is moving into Western Canada from Southeast Alaska is bringing vorticity maxima as well as moist southeasterly flow into the Interior. While temperatures will remain marginal for convective initiation the vorticity and moisture advection can help to provide synoptic scale lift for thunderstorms today and tomorrow. This energy will stick around in the Interior, as there isn't really anything to move it until we see high pressure move into the region later this weekend.

Friday night an arctic trough will begin to dig south into the Interior. There is not a lot of cold air aloft associated with this trough, so temperatures will slightly cool on Saturday, but the main threat will be isolated thunderstorms in the Central Interior. These thunderstorm chances will heavily depend on the timing of the trough, and if it can align with peak heating. The ECMWF has the trough currently hung up on the Brooks Range, so the threat for thunderstorms would be there. Compared to the GFS/NAM solution where it has the trough axis from Galen to Fort Yukon. While the difference isn't that large, as we begin to transition to a warmer and drier pattern early next week, any fires started from the lightning could see growth when we get into the warmer and drier pattern. This warmer and drier weather will talked about in more detail in the Extended Forecast Discussion.

FIRE WEATHER

A series of low pressure systems are rotating around Alaska, keeping fire weather conditions moderate for the near future. Temperatures will range from the high 60s to mid 70s through the weekend, except in the eastern Interior where cloudier and rainier weather will keep things a little cooler. By the start of next week, it will get warmer, as high pressure from Siberia moves over Alaska. Tuesday looks like it will be the warmest it has been in a will be while for most of the Interior, with temperatures reaching up to the mid 80s. Relative humidity will bottom out in the 35 to 25 percent range for rain free areas through the weekend.

Northerly winds build in from the east into the Yukon Flats on Thursday and will become breezy for the entire Interior on Friday and Saturday, but only up to about 10 mph.

The highest chances for wetting rain will be in the Eastern Interior Thursday night into Friday. Otherwise, chances for precipitation will be limited to light showers and a few isolated thunderstorms. Chances for thunderstorms will be greatest in the southern Interior on Thursday, although high resolution models are also showing thunderstorms tracking over the Yukon Flats and southwest Interior. Friday looks like the best day for more active thunderstorms. The best chances will be in the Western Interior, but the Upper Tanana Valley will likely get some as well. The lack of wetting precipitation beyond the Eastern Interior means that fuels will be getting steadily drier through the rest of the week.

EXTENDED FORECAST DAYS 4-7

Sunday through Tuesday

A Siberian ridge will gradually be shifting east and placing itself directly over most of Northern Alaska. This allows a warm bubble of air to be draped over the area allowing for a period of warmer than normal temperatures early next week for much of Northern Alaska. 850Mb temperatures may approach 10C to 15C across the Interior with values near 5C to 10C for the North Slope and West Coast. These temperatures support surface temperatures in the low to mid 80s in the Interior Valleys and 60s/70s along the West Coast and North Slope. At the very least it will be much warmer and drier than what we are currently seeing. Early next week there will also be a low in the Gulf. The combination of a low in the Gulf and high over the Brooks Range brings easterly flow to the Interior. This type of pattern would likely lead to areas of scattered thunderstorms across the Interior. Thunderstorms, in addition to potentially hot and dry conditions may result in an uptick of critical or near critical fire weather danger.

Coastal Hazard Potential Days 3 and 4...None

AFG WATCHES/WARNINGS/ADVISORIES

AK...Winter Weather Advisory for AKZ801>803. PK...Small Craft Advisory for PKZ806-807-811. Small Craft Advisory for PKZ817. Small Craft Advisory for PKZ854. Small Craft Advisory for PKZ856. Small Craft Advisory for PKZ857.