So as the news anchors are talking about what the fork's going on, Yujiro is just kinda casually walking as he's being hit in the face with lightning. Yeah, they're looking at a still image, but the meteorologist then goes on to talk about how it lingered about for "Quite some time".
The energy of a lightning bolt is about 5 billion joules
I'll assume "Quite some time" is about 5 seconds, as if you kinda sit there and count it out, it is a bit of time, especially in comparison to an instant event like a lightning bolt, which is only .2 seconds. Meaning, our bolt of lighting would have 25 times the energy of a normal one.
25 times 5,000,000,000 is....
125000000000 Joules, 29.8757170172 Tons, City Block level
Of course, 3 seconds is also a bit of time, so that could serve as a lower end.
3 divided by .2 is 15, 15 times 5,000,000,000 is...
75000000000 Joules, 17.9254302103 Tons, City Block level
While this initially seems wanked since it's calculating the total energy of the lightning, which someone standing on the ground wouldn't have to deal with the entirety of, it's actually directly stated in the manga that the lightning hit Yujiro and had no where else to go (despite there being several more efficient ways to travel), which of course defies normal logic but, hey, Baki.