Good to see Cardiff had a decent turnout, and some new faces.
Forecast looking pretty good as of this moment for Westminster (20C, sunny intervals). Brighton...a lot less good but the lack of sunshine usually means a better standard of images. It was a nightmare in the harsh midday sun at The Level last year. 2013 was the best one I've done, light wise. Ideally you'd have light cloud cover, no wind and very high temperatures, to ensure everyone has a dip in the fountain, extended rest stops and a long skinny dip on the beach.
2012 had about the worst conditions you're likely to experience in June in England. Max temperature of 12C, cool winds, heavy rain throughout the ride. But it was still a good turnout and the weather made for a much smaller number of idiots who get in your way
Down side was much shorter rest stops at Hove Lawns and Old Steine, and very few bothered with the beach at the end.
Temperature is the key. I think very humid conditions and rain would probably make for a very interesting event. Unfortunately we're not likely to get much in the way of heat down on the coast this Sunday, so we'll have to hope it at least isn't too windy or wet.