How strong is a magnitude 5.8 natural disaster?
There were no immediate reports of injuries, according to the Lewis and Clark County Sheriff's Office.
Helena, Montana, the state's capital, experienced moderate shaking in today's M=5.8 quake.
There are reports of power outages around the center of the quake near Lincoln, MT. Many people awoke to rattling windows.
Missoula Police Department Corporal Mick McCarthy said property damage has not yet been reported.
"They aren't common, they don't happen as often or as frequent as they do on the west coast", she said. A magnitude 4.5 quake rattled the same area about five minutes later. It caused significant damage, but no fatalities.
Montana Resources Vice President of Human Resources Mike McGivern said the mine didn't experience any damage. For residents in Spokane, which is the second most-populated city in Washington State, it will be particularly shocking.
An quake of that magnitude can cause damage to poorly constructed buildings but as most, none to slight damage to all other buildings.
Baldwin told the broadcaster that there have been 16 earthquakes of magnitude 5 or greater within a 300-kilometer radius from the epicenter in the last 100 years. The largest was the August 1959 M 7.2 Hebgen Lake natural disaster - the largest historic event in the intermountain region - which occurred about 280 km to the south-southeast of the July 6th event.style="text-align: center;"