From personal experience.
DO NOT!!! have a large curry and bavarian lager supper if there is a chance of the weather improving.
I was booked in for circuits in the afternoon when my phone went, only to be told that it was CAVOK and to head up to the airfield for the route that I had obviously had planned out.
Luckily Cabair had parked a tupperware trainer in a field and so my take off was delayed until nature had taken its course and I had cleared all systems ready for my flight.
I hate to think of the state I would have been in on arrival at Gloucester.
30.06