PALMER — It’s not often that Southcentral Alaska residents wake to thunder in the middle of the night.
But what forecasters are calling an unusual storm moved from the Talkeetna Mountains into the Matanuska Valley and then Anchorage and south to the Kenai Peninsula from Wednesday night into Thursday morning.
At least one lightning-caused structure fire was reported.
Crews from Central Mat-Su, Palmer and West Lakes fire departments responded to a fire on the roof of the Grand View Inn & Suites in Wasilla for a lightning-caused fire, according to Ken Barkley, emergency services director for the Matanuska-Susitna Borough.
Wasilla resident Chris Reynolds, a guest at the hotel, said in a Facebook post that the “monster” storm hit Wasilla around 2:30 a.m. Lightning struck the top of the building.
“I felt the building shake on the last thunder clap,” Reynolds wrote. “Shortly after people were banging on the door yelling at me to evacuate.”
Contacted Thursday, he said firefighters advised him he probably couldn’t stay at the Grand View so he found another place to stay.
No one answered the phone Thursday morning at the hotel. Damage was isolated to the attic after fire crews opened up the hotel roof, Barkley said.
No other lightning-related structure fires were reported Wednesday night or Thursday morning in Mat-Su, he said.
It wasn’t immediately clear whether the storm sparked new wildland fires, according to an Alaska Division of Forestry fire information officer.
Numerous fires, some started by lightning, were already burning around the state, including several near Talkeetna. A lightning-caused tundra fire near the community of St. Mary’s by Thursday had grown to nearly 50,000 acres and was burning within 8 miles of the village near the Yukon River.
On Wednesday evening, the first reports about the large thunderstorm system came in around 11 p.m. and continued into Thursday morning in Kenai, according to Tim Markle, an Anchorage-based meteorologist with the National Weather Service, who said around 8 a.m. he was still tracking the storm on radar as it rumbled south toward Ninilchik and Anchor Point before an anticipated path to Southwest Alaska.
Southcentral Alaskans are more accustomed to what Markle called “popcorn variety storms” that rise over the mountains on warm days and drift over populated areas in late afternoon or evening before dissipating.
This kind of big overnight storm that’s slowly moving over a broad area is unusual, especially over Cook Inlet, where the cooling effect of water often defuses storms.
The Weather Service received reports of thunder, hail and rain from Palmer and Wasilla to Eagle River to East Anchorage to the Kenai.
But, as is typical with early summer storms that lack the moisture of those in rainy August, precipitation was highly variable, according to Rick Thoman, a climate specialist with the International Arctic Research Center Alaska at the University of Alaska Fairbanks.
One Eagle River gauge registered three-quarters of an inch from the night storm, Thoman said. Another gauge at Merrill Field measured seven-hundredths of an inch, while a few blocks away people reported water running down the street from the deluge.
The overnight thunderstorm was “quite unusual” for the Anchorage area, he said. “They’re unusual anywhere, but typically where we see them is farther north.”