Spa is already a lovely track in the calendar and there is more! On Saturday and Sunday both rain is expected. As far as I can see it is more likely during the sprint and race.
After leaving a rainy Silverstone race behind are you ready for another one with probably lots of action?

Normally I don't like sprint format at all but rain can make it more interesting thankfully.

Im not familiar with the particular weather of Belgium, but we are not only have rain but also a pretty cold day right?. I mean europe is in summer and that temperatures in the picture above are more like fall. So the grip can be a big trouble for the teams even if the rain goes away.