I choose this person's basement

So a quick check on this, For a 50 megaton airburst on that city 30 miles away (bit closer by the crow flies) I am within the third degree burn radius and the light blast damage radius, However some basic trig and an altitude map say I have no direct line of sight to the airburst assuming its detonated at an altitude of 1km, so I'm free and clear as far as third degree burns are concerned due to that being a product of the flash. As for light blast damage its likely somewhat lessened by the lack of line of sight and very bumpy intervening terrain, though my village is right along a major river and gives us a comparatively straight (by the standards of river valleys) run right to that city so window breaking is probably going to be pretty hit or miss depending on building orientation and local obstructions.

There's also about 250m of elevation between Glasgow and Edinburgh which is fairly significant considering they're 50km apart, a rough eyeball on an elevation map suggests that they each get at least partial obscurity from a nuke dropped on the other.