Can you seal a hot tub leak in the winter?

I live in Michigan and have found a leak in my hot tub. Is there any substance I can use on outdoor plumbing that will seal in the cold. The average outside temp right now is mid 40's to lower 50's (on a good day) and alot colder at night. I really don't want to lose out on using the hot tub all winter!!! The hot tub is currently empty and dry