So here's the deal: my story takes place in modern America in the aftermath of an unexplained event where a runic magic system was introduced to humanity by an unknown entity. Every week a new rune is given to everyone on Earth over the age of 13, and everyone can keep any six of their choosing before having to give one up to make room for the next week's rune. Each rune represents a supernatural power the bearer is capable of using.

One of the biggest difficulties of adapting society to this new paradigm is that there's no way anyone can tell what new power everyone's going to get next Saturday at 12:00 PM EST. Mounting concerns about potential unpredictable consequences of future runes, and mounting distrust of the motives of the unknown entity providing the powers, eventually prompt governments to start safeguarding against potential accidents. And the American government decides that it wants everyone off of the roads and on the ground during an hour long period every week, from 11:15AM to 12:15PM EST, to make sure that if something unexpected and dangerous arrives on the rune pipeline one week, it doesn't result in massive, deadly, infrastructure-crippling pileups on all major roadways.

The additional Doylist reason for this is because by the end of the first book, one of these runes will cause total societal collapse by disabling all technology that runs on electricity, and the main villain's plan ultimately makes this last way longer than one week, thereby plunging the setting into post-apocalyptic territory. And for various storyline reasons, I want the roads to still be usable, and I don't want to have to wait until massive organized efforts to get the useless cars off of highways can happen before I can do these things.

But my main issue is that I don't know for certain if such a law would be constitutional, passable, feasible, or even enforceable in practice. Would it be?

Would there be any fundamental issues I'd have to address in order to justify an hour-long period on Saturdays when everyone has to keep their vehicles parked and off of the roads and all planes are grounded?