Idaho State Journal report
Severe thunderstorms, hail, strong winds, heavy rain and unseasonably cold temperatures are possible in East Idaho starting Thursday morning, according to the National Weather Service.
The stormy weather, which is expected to continue into Friday, comes with the potential for tornadoes because of the strong cold front that's forecast to move through East Idaho, according to the weather service.
People planning to spend time in the mountains should prepare for winter conditions, said weather service meteorologist Jack Messick at the Pocatello Regional Airport. He said snow is expected to accumulate in the mountains and could get as low as 5,000 feet.
“It won’t be nice hiking weather,” he said.
That follows a string of one tornado and two funnel clouds in East Idaho on Sunday. The tornado was near Bone, which is northeast of Blackfoot. He said the weather service recently got people out to confirm that the funnel cloud near Bone touched down, which means it can be termed as a tornado.
Idaho typically sees five or six tornadoes a year on average, but there can be more, , Messick said.
Recently, the state has been getting cold air from Canada meeting warm air from the Gulf of Mexico. The difference in temperatures provides ideal conditions for thunderstorms and even tornadoes, he said.
“It takes a severe thunderstorm to generate a tornado,” he said.
And the bigger the difference in temperature between the cold air and the warm air, the stronger the tornado, Messick said.
The tornado that hit East Idaho on Sunday is considered the weakest category at EF0. But that means the wind speeds are still 65 mph to 85 mph and that’s hurricane strength, Messick said. That can damage trees, mobile homes and other structures. Cold temperatures are also expected.
“It’s very unusual this time of year,” he said.