It must be at least 40 degrees Fahrenheit or above for 6 hours in order for the paint to adhere and begin to cure properly. The dew point is more important than temperature, but that is a more complex calculation. If you are in question, it’s probably to close to call, and we suggest you just wait for warmer weather. A long lasting paint project will cure completely without frost or freezing and not be subject to moisture early in the curing process.