What if it rains right after you have your windows professionally cleaned? You just paid good money to have your windows cleaned and wouldn’t you know it, it rains. Just like when you wash your car. So now what? Not to worry. Rain doesn’t necessarily spot windows. Rain on a dirty window does. You see once your windows are professionally cleaned there is an amount of time where the surface of the glass is free from any contaminants or dirt. If it were to rain during that time, the water from the rain is pure, and will evaporate spot free. So when you have rain water land on a clean piece of glass there is a better than 99 percent chance the rain water will dry spot free on your window. Spotting from rain water usually occurs when the window is dirty. Rain water mixes with the dirt on the window and that’s what causes the window to spot when the window dries. But for your peace of mind its always a good idea to ask your window cleaning company if they offer a rain guarantee. Some don’t. Some offer outstanding rain guarantees. So use this information to your advantage the next time you decide to have your windows cleaned professionally. Hope this helps.