A strong storm in the Bering Sea is expected to bring high winds and widespread flooding to a large swath of the Western Alaska coast starting early Friday morning (Oct. 23).
According to the National Weather Service, Hooper Bay could see water levels as high as 7 feet above the normal high tide line and wind gusts as high as 70 miles per hour beginning early Friday, and extending into the evening.
National Weather Service meteorologist Alekya Srinivasan said the storm’s south to southeasterly winds will be less impactful than the southwest winds typically associated with coastal flooding in the region.
"The wind direction makes a large difference in what communities may see. Since we are expecting south-southeast flow, that's why we're expecting Hooper Bay to be one of the more impacted areas from this system," Srinivasan said.
Srinivasan said water levels of 4.8 feet or higher above normal high tide generally trigger a flood warning for Hooper Bay, reducing access to the community’s airstrip and cutting off access to some sections of town.
The storm is followed close behind by a second Bering Sea low-pressure system that has Hooper Bay and the rest of the Yukon Delta Coast under a coastal flood warning through late Sunday evening (Oct. 25).
"We are expecting water levels to gradually decrease through the weekend, but they won't return to normal high tide line for a few days as we do get that second system moving in, which would pretty much elevate the water levels once again," Srinivasan said.
Down the coast
Down the Kuskokwim Delta Coast, the communities of Kipnuk, Kwigillingok, and Kongiganak are under a coastal flood advisory from early Friday morning through 1 a.m. Saturday morning.
National Weather Service meteorologist Josh Ribail said the worst-case scenario would bring water levels up to 5 feet above the normal high tide line in Kwigillingok, but that maximum levels of 3 feet above the normal high tide line are far more likely.
"As for impacts, we're expecting [flooding of] low-level structures that are not on stilts, and maybe some boardwalks for the most likely scenario," Ribail said.
A high wind warning has also been issued for the interior Kuskokwim Delta. Sustained south to southeast winds as high as 50 miles per hour and gusts as high as 75 miles per hour are expected to impact communities along Kuskokwim Bay and upriver to Bethel through early Saturday morning (Oct. 24).
Ribail said meteorologists are closely monitoring the possibility that the second storm in line could bring a shift to southwesterly winds for the Kuskokwim Delta coast — and with that shift, more flooding.
"It’s something of concern. But there's a decent amount of uncertainty with that one — how strong the winds will be, where the core of those winds will be as well, and how much fetch we're going to get," Ribail said.
The Alaska Division of Homeland Security and Emergency Management said it has increased staff on standby through the weekend available to respond in case communities are severely impacted.
