Extra-Tropical System Makes Way Up Alaska’s Southwest Coast

The storm system making its way up the southwestern coast of Alaska is bringing rain and high winds.

Download Audio

This is a large weather front. Very large.

“It is just such a massive system. It is releasing a lot of energy,” Michael Lawson, a meteorologist with the National Weather Service, said. He says after this has moved through, there are only a few places in Alaska that won’t have felt its effects.

“By the time it reaches its peak intensity, it will encompass most of the Bering Sea and the frontal boundary that’s associated with it will stretch all the way up into the Brooks Range and then down south over the Southcentral,” Lawson said.

Lawson as the frontal boundaries push up against the northern gulf, a mass of air gets pushed up against the coastal mountains and has nowhere to go. It gets forced into places like Turnagain Arm and Portage Valley.

“As this air gets funneled through these gaps, there’s a lot of pressure built up on the Prince William Sound side and it’s got to relieve itself in some way,” Lawson said. “So, the air gets accelerated through these channels and can manifest itself in very, very strong winds. That’s likely the situation we’re looking at here.”

Lawson says the Turnagain Arm area can expect to see sustained winds of 30 to 50 miles per hour with gusts of 60 to 80 miles per hour over the next few days.

The heaviest rains are expected to fall in the Seward and Cordova areas, with three to six inches projected along the eastern peninsula and north gulf coast through Saturday.

“With the strong southeasterly winds that are going to be the main force behind the wind in Turnagain Arm, the mountains are going to block a lot of that moisture for the Anchorage area and the Western Kenai Peninsula,” Lawson said. “The majority of it is going to be condensed out on the eastern Kenai mountain side.”

Lawson says as of Thursday afternoon, the system was gaining intensity near the Western Aleutians.

Jason Ahsenmacher is the meteorologist who covers the more western regions. Although it’s massive, he says this extra-tropical system isn’t too out of the ordinary. It’s just the first big storm of the season.

“It’s like anything, whether it’s the first snowfall in Anchorage or whatever,” Ahsenmacher said. “There’s always that shock to the system type of thing that you get when you have the first of anything.”

“So, I think that’s why we’re really trying to get the word out, especially for the local communities along the Bristol Bay coast and into the Kuskokwim delta.”

Ahsenmacher says there will be strong winds along the southwest coast of the mainland from Bristol Bay to the Kuskokwim delta.

“They’re going to be looking at max gale force winds,” Ahsenmacher said. “So, winds along the coastline will be gale force of 45 knots and then inland, we might be seeing some gusts as high as 60 – 65 miles per hour. So, this is going to be a pretty big impact for not only small craft boaters, like in Bristol Bay, it’s going to be quite windy across the mainland as well. So, that’s going to be an impact for hunters and people who are out recreating.”

Over the next couple of days, the system will cover the entire Bering Sea. As it develops along the Aleutians over the next 24 hours, Ahsenmacher says the central and eastern chain can expect heavy rain.

“Areas like Atka, Adak, through Dutch Harbor, that’s going to be where the bigger impact is,” Ahsenmacher said. “We’re looking at the potential for 75 mile per hour winds across Adak and Atka and possibly 75 mile per hour winds across Dutch Harbor as well.”

While coastal Alaska does get pummeled by storms every fall, this is definitely a large one. Over the next few days, residents should take precautions if they plan to recreate, hunt, or fish in affected areas.