BOISE, Idaho -- An earthquake shook the Boise area about 5:53 p.m. Mountain Daylight time on Tuesday, according to the U.S. Geological Survey.
The shaking was reported to last for 20 to 30 seconds, with a small pause.
U.S. Geological Survey pegged the earthquake at 6.5 magnitude with an epicenter in the mountains northwest of Stanley. The epicenter was about 28 miles west of Challis, the National Weather Service said.
There were at least five aftershocks, according to USGS: a 4.6 at 6:27 p.m., a 3.6 at 6:01 p.m., a 3.4 at 6:49 p.m., a 3.5 at 7:03 p.m. and a 3.3 at 7:13 p.m.
Stanley Mayor Steve Botti said as of 6:15 p.m. he hadn't seen any damage in his town yet.
"Stuff was flying all over the place," Botti said. "I was upstairs and I tried to walk down the steps and I couldn't because it was shaking too much." According to the Idaho Statesman archive, the 6.5 magnitude would be the second-largest earthquake in Idaho history if it stands (the number often is adjusted with more information). The Borah Peak earthquake, which was a magnitude 6.9, killed two people in Challis near the quake's epicenter. The second-largest is a three-way tie at 5.8 from 1983-84.
The five strongest previous Idaho earthquakes were all in the Challis area.
Expect more earthquakes in the days to come, USGS says. There's a 99% chance of aftershocks of magnitude 3 or higher and a 48% chance of a magnitude 5 quake or higher, its forecast says.
"According to our forecast, over the next one week there is a 4% chance of one or more aftershocks that are larger than magnitude 6.5," the USGS forecast says. "It is likely that there will be smaller earthquakes over the next one week, with 4 to 790 magnitude 3 or higher aftershocks. Magnitude 3 and above are large enough to be felt near the epicenter. The number of aftershocks will drop off over time, but a large aftershock can increase the numbers again, temporarily." "We don't have any reports of damage just yet," Hayley Williams of Boise Police said.
"We haven't sent any first responders out -- police or fire," Stephany Galbreaith of Meridian Police said.