>>345616Not sure really, probably a combination of a humid evening, a stream nearby and our campsite shaded by trees.
It would have been lovely if not for the miniature demonspawn that would converge on our position no matter where we moved to. Found this when I got home and started looking for a solution:
http://midgeforecast.co.uk/Only for Scotland unfortunately, but still worth keeping bookmarked.
Pic is of a much less annoying insect plaguing our chosen pitch.