A lightning bolt is hotter than the surface of the Sun

The air a bolt of lightning passes through can reach some 30,000 kelvin, five times hotter than the surface of the Sun, which is around 6,000.

The reason is that air is a terrible conductor of electricity. When a discharge forces its way through it, it heats it all at once until it turns into incandescent plasma. That brutal, instantaneous heating expands the air explosively, and that shock wave is what we hear as thunder.

All of it lasts a fraction of a second. In that instant, a piece of the sky above your head was hotter than the face of the Sun.