Xylol or naptha are both fairly slow solvents. They give good wetting, and allow the paint to flow out nicely. Down side is you are more likely to run the paint in those conditions. 60 degree weather is a little colder than I like to paint in. If you just have to, use a faster solvent, unleaded gasoline actually works quite well. Put on several light coats and watch how it flows. If you try to hammer on a full build coat all at once, you will likely have some drips and sags on vertical surfaces.