I think this lot of House Martins are a little early to be gathering for their Autumn flock!
So that's what blue sky looks like!!
Nice photos Chrispy, they are still around here just outside Sheffield but not in any great numbers so you may have some of mine.
My photos are on Flickr and Website
It's been around 98°F round here today so they're probably just sitting around topping up their tan!
It's warm here but very humid/cloudy/raining typical summer weather.