Not great prospects at the moment, but thanks for the forecast, hopefully it might improve.
One criticism though, the span of your forecast. Glastonbury is no longer a 3 day event day event. All of the 25,000 extra attendees for this this year will be arriving on Wednesday 20th and many of the minor stages will have stuff going on from Thursday. I'm sure I read somewhere that getting on for 50% of ticket holders arrive on the Wednesday (this rings true from my experience), so all in all, there is likely to be 100,000 people plus there from Wednesday 20th. Also, the site will still be full on the Monday morning and for a large part of the day. So, if your forecast only runs from Friday to Sunday, it will only really be 50% of a forecast, if you see what I mean... Put that right and you'll be a bit more credible than the other forecasters out there (with the exception of Glastofestivalforecast of course)