Probably a safe bet. It absolutely piddled down on the last two times I've been there.

They also have a ridiculous array of glamping options too. (If you're a rich knob who has a spare 3.5K to blow on an American diner trailer thing for a 4 night festival stay, hahahaha!)

https://discoverthebluedot.com/accommodation/

also has info on how to bag your campervan spot.

I have been fortunate enough to go to four of them now, and here's what I've learnt:

Getting there on a Thursday, even if it does involve paying something like £30 extra just for that day (which typically features only one headline 'guest' band) is a must. This is because the campsite fills up really fast.

Bluedot is quite an odd one compared to other festivals of a similar size (15k ish) because it sells day tripper only tickets - so the crowd swells in numbers in the evening, considerably so when the main headliners appear.

If you stand too close to the front (like I did with the Mogwai performance last year) you will miss out on the lazer show on the giant radar telescope dish!