Drying times can vary quite widely based on a few factors (in decreasing order of importance). (1) Air temperature (2) Direct sunlight (3) Asphalt temperature (4) Wind. The sealer is a water-based product and, just like paint, will dry when all the water evaporates out. Sealer applied in direct sunlight on a 90-degree day can dry almost instantly. Sealer applied in the shade when temperatures are less than 60 degrees can take 48 hours or more to dry. Under most circumstances, if applied in the morning, sealer will take 2-4 hours to dry.