One weapon, one single event will not wipe out the entire power grid in the US. Multiple, simultaneous events might bring down a good portion of it though, at least temporarily.
Jericho — pretty good mini series.
I get a kick out of people that say an EMP wouldn’t do anything. Hello, Carrington event? Melted thick solid copper telegraph lines, electrocuted operators and set stations on fire.
https://owlcation.com/stem/massive-solar-flare-1859
Satellites being affected by a solar flare is a big concern. Some nukes set off high enough might affect low orbit satellites too. I don’t know if a man made emp could be powerful enough to burn up large transformers or not.
The next solar maximum is 2024 but it seems like the late 1800s and early 1900s had more activity than anything since.