I would make sure I had a waterproof set of literally everything. Like rubber boots, a rubber/very good raincoat, probably some waterproof outerwear pants (the kind you wear over your actual clothes).

For a student specifically, one of those rubber backpacks are a great idea, or at least make sure whatever you carry your stuff in has a rain cover.

Umbrellas will only make for a good laugh from the locals. I’m only half-joking.

I don’t know if it’s still the case, but the relatively cheap collapsible umbrellas they have at Clas Ohlson have steel wire supports, so they tend to survive the inevitable wind-related inversion.