Football and Thunderstorms...

Tornado passing Bryant-Denny Stadium at the University of Alabama
on April 27, 2011. No game was in progress.
Photo: "Birmingham News"

...don't mix. There will be multiple opportunities for high school and college games to be affected by thunderstorms and worse Friday and Saturday. Here are some thoughts.

1. Most important rule: Trust your instinct. If things don't look or feel right, shelter regardless of what others might chose to do or not do. 
2. Lightning is a threat in every thunderstorm. Your car offers adequate protection and is superior to some types of stadia. 
3. "Severe" thunderstorms are those with large hail (≥1") and/or damaging winds (≥58 mph). If there is shelter available in a permanent building (i.e., the high school itself) that would be preferable to your car or under the stadium. For most high school stadia, I'd chose my car in a severe thunderstorm.
4. Neither car nor stadium is adequate shelter in a tornado and there is a pretty good chance of at least a few tornadoes Saturday. If a tornado watch is issued and thunderstorms begin to approach, I would probably bail out in plenty of time to get to more substantial shelter long before a traffic jam develops.