for the most part, as long as the shop area is kept above freezing no major problems should occur..unless you are working in the tenths range, heat expansion from cutting can alter your end result..
below freezing conditions screw up things like coolant, power loss from turning gears in the equivalent of grease, etc..
I only heat my garage / workshop when I need it, and condensation has already caused some fine surface rust on my new 10" chuck on an old Gisholt lathe..and other items as well
??enjoy..