Went last year and weather was fantastic. Not going this year though.
The weather at the moment near Longleat (I am currently about 3 miles away) is good enough for flying, no low cloud, looks to be at about 4000 ft towards longleat.
Longleat sits down at the bottom of a hill so hopefully it might be a bit protected from the elements.
Hope the weather is good for tomorrow.
Watch the traffic at the end though! Last year me and a friend walked out of the venue past all the queuing cars and were home in 20 mins. Got my Dad to pick us up down a country lane!