Happy Monday! Rainy days are my favorite. We are located in Elk Grove, Ca, so we are far from freezing temperatures; however, every cold rainy day I have at least one customer ask if it is okay to tint windows when it is raining. The answer is yes.
Quality films that use a pressure sensitive, non-dyed adhesive have no problem bonding to glass that has been properly prepared for mounting. Colder temperatures do mean that the adhesive will take longer to cure. The moisture that is present in freshly tinted glass will take longer to dissipate. These conditions can actual help the installer to QA (quality assure) the installation, as he/she is no longer working with film that may dry as soon as it is pulled into direct sunlight.
Professional window tinting operations are open year around...rain, sleet, or snow. When prospecting for a store it is always important to ask what type of film will be installed. You want to make sure the film is not a low quality, dyed adhesive product. Films that use a dyed adhesive layer are often single ply and will have long term issues with adhesion.
I remember years ago when I thought tint was tint. I could not have been more misinformed. Again, it is safe to tint your windows during cold weather. Stay warm and be well.