Late showing of the Noctilucent Clouds.
The night of August 11/12 was the first clear, starlit night for many weeks, a welcome relief from the almost continuous cloud cover we have had to endure this summer (though, be it noted, rainfall has been exceptionally low).
This night gave some spectacular meteors from the Perseid shower and a late showing of the tenuous, silvery noctilucent clouds.
Full details on the Northern Skies site at http://www.spanglefish.com/