Aleutian storm season opens big with 120 mph-gusts in Unalaska over the weekend

Unalaska pictured after high winds tore across the island in the early morning hours on August 30, 2020, with gusts recorded as high as 120 mph.
Unalaska pictured after high winds tore across the island in the early morning hours on August 30, 2020, with gusts recorded as high as 120 mph. The Department of Public Safety issued a travel advisory at 8:30 a.m. due to, “extremely high winds and large flying debris.” (Hope McKenney / KUCB)

A storm early Sunday morning in Unalaska recorded high gusts of 120 mph. The strong winds toppled boats, threw shipping containers into the bay and even blew the windows out of American President Lines’ crane.

The rapidly developing storm, which moved from the North Pacific and across the Eastern Aleutians, was an intense storm for this time of year, according to climatologist Rick Thoman.

“It appears this was the strongest storm to affect Alaska during the month of August on record,” said Thoman, who works for the Alaska Center for Climate Assessment and Policy.

He said in addition to the widespread reports of high wind gusts across Unalaska, there were gusts of around 80 mph reported farther northeast along the Alaska Peninsula and even into upper Bristol Bay.

Thoman said the origin of this storm has been the topic of considerable discussion within the Alaska weather community over the past 24 hours. The storm might have been fueled by Typhoon Bavi, Thoman said, which moved into the Korean Peninsula late last week.

“It raised eastward from north of Japan across the North Pacific, and then crossed the Aleutians near Unalaska,” he said. “The question that we’ve been discussing is was this in any way a piece of, or sparked by Bavi? It certainly wasn’t a classic typhoon turning into a big Aleutian storm, but Bavi may have supplied some energy for this storm that impacted the area.”

This kind of storm is out of the ordinary for the summer months, according to Thoman. He said Unalaska may see similar events happen in October, November or December, but Sunday’s event appears to have had the lowest atmospheric pressure of any August storm on record for the state — which likely contributed to the very high winds across the Eastern Aleutians and Alaska Peninsula. And, he added, a changing climate could also be a contributing factor.

“Most of the North Pacific Ocean surface temperatures are warmer than normal: virtually the entire Bering Sea ocean surface temperatures are warmer than normal,” Thoman said. “It’s not a lot warmer than normal, but with water, even a small difference supplies extra moisture and energy to the atmosphere. So that could have played a role.”

Thoman said the rapidly-moving storm is a good reminder that we’re moving into the storm season. And while he said he doesn’t necessarily expect a repeat of this combination of events, it’s always good for Unalaskans to be prepared.

Reader Interactions