The best time to seal your parking lot or driveway is during the summer and fall. Winter is not a good time for sealing because the colder air will affect the performance of the sealant and may not cure properly. Sealing is best performed in warm and dry weather. You should seal your driveway in the fall or summer when the temperature is at least 60 degrees Fahrenheit. In the summer, it is best to seal your driveway in the morning before it gets too hot. Make sure that before you seal your driveway you look at the weather forecast to see if it is going to rain. If it is, it is best to wait to seal your driveway a different day.