Do you actually have good weather?
Elle seemed to be talking of 'dull and humid' day, though warm.
Here, it has clouded over a little bit just now but it is still bright, with decent temps. At least it does not look like rain and I hope it will remain dry tomorrow because, being the longest day, it is the 'fete de la musique' day.
This means that just about everywhere in France there is music of some sort going in the street, usually a local band or a single musician (accordeon being the old favourite) .
The whole is often organised but cafes and dancing takes place outside their place, in the street.
In my village, there are 4 cafes/brasseries (+ a good restaurant, a kebab place and a pizzeria which does many other dishes apart from pizzas), so there is a wide choice of venues with different music style on offer.
All this is free but the cafes make their money on the drinks and snacks they sell.
On top of this, most villages also have a 'fanfare', and they will march through the town centre merrily blowing on their various brass instruments. All this makes for a joyful but noisy event starting from 3/4 pm and going on more or less until whatever time the cafe owners want, because they are granted an all-night permission on that day.
There you are for a bit of useless information!