In 1958, Sports Illustrated had Thunder with 4 miles of trails, a 2400′ poma lift with a 510′ rise and 4 rope tows. The previous year it had been open 100 days and served 7000 skiers. New for 1958 were a 2100′ rope tow, a new run, lodge improvements, ski patrol room, and ski school dorm.
On Feb. 3, 1966, The Cass City Chronicle printed the AAA guide to Winter Sports Fun in Michigan. It listed Thunder as having 12 runs from 1600 to 3000′ long, beginners area, T-Bar, Poma, and 2 rope tows.
One of the comments below claims Thunder was opened by the parents of Cary Adgate, former US Olympic Ski Team member and Pro racer who was inducted into the US Ski Hall of Fame in 2008. If Thunder was opened in 1958, Adgate would have been 5 years old, and probably learned to ski there.
Later, Thunder Mountain was purchased by Ev Kircher as one of the parts of the Boyne Country Development.
Now abandoned, with the lifts long stripped, it is the site of sledding runs and poached ski runs. For a hilarious commentary and some fabulous pictures from an ascent in 2009, see http://www.tetongravity.com/forums/showthread.php/179708-TR-Thunder-Mountain-MI
If you have any information about skiing at Thunder Mountain, please post it or send it to us via the directions on the About MILSAP page.
On a recent trip to Charlevoix county I took a picture of the former area from the driveway. The day was very foggy, but I could read the signs at the gate: Posted, No Hunting, No Trespassing, Video Surveillance, Live Fire Zone.
Here are some early pictures of Thunder Mountain from the Adgates, passed along by John Shepherd.