What can cool a surface down?
To cool a surface down requires heat (energy) to be removed from that surface. When you apply a coat of paint to a surface the paint will absorb heat (energy), which then gives the solvents sufficient energy to evaporate from the paint film. This process continues until all the solvent has evaporated. The removal of energy from the object cools the surface down. You will experience this if you spill gasoline, solvent or alcohol on your skin, as it evaporates it cools your skin down. Remember that surface temperature is different then ambient air temperature and must be measured with a surface thermometer to decide whether the surface is high enough above the dew point to allow you to paint. For example a steel hull will be cooler on the shady side compared to the sunny side. In the morning the sunny side will generally be lower than the ambient temperature where as in the afternoon it may be higher. What is relationship between relative humidity and dew point? The following chart shows
