A corollary of the Fresh Air Is Always Good doctrine is that weather doesn't matter. Being outside is ALWAYS good for you. When I was in daycare/preschool, we spent half the day outside. Every day. Usually a few hours in the morning and a few in the afternoon. I disliked bad weather at an early age and really preferred being inside playing, but there was no mercy. Norwegian daycare is still like that. I see kids outside all day, all year. Most daycares will have a large outdoor area with lots of stuff to do.
This is a typical daycare facility:
And here are some kids I found online. The part that makes my friends laugh is that it is considered very convenient to line the kids up, all dressed in their heavy duty rain gear, and hose them off with the garden hose! They will be messy from playing in the mud (we have a lot of mud in Norway) so what better way to clean a lot of kids really fast??