Any suggestions for where to hold a winter Boot Camp?

I actually read your question a bit differently than Marlan 🙂

Perhaps you are doing your Boot Camp outdoors in the Spring-Autumn months and are looking to continue on into the cooler winter temps.

You may look into moving your boot camps indoors by looking to rent space for say the 3-4 months of winter.

I teach at a martial arts school and do a Sat. morning boot camp. The owner was approached by another outside boot camp instructor who asked whether he could use the school on Sunday mornings.