Well, not actually seeing it, as the snow was too heavy but (perhaps because of the snow), the flash seemed to be FAR brighter than you would expect in a "regular" electrical storm. Ever get dazzled if you (accidentally, of course) look directly at lightning? Well, it was like that but in every direction. It didn't seem to matter if the lightning was behind you... you still got dazzled. (And I was driving at the time: icy roads, thick heavy snow, and brightly flashing sky in all directions... I would rather have been hiding in my wardrobe!)
It was pretty eerie and, having consulted Mr. Google earlier, I appear to have witnessed a somewhat rare meteorological event.
Thankfully, normal rain service has resumed today.