Once the window is cleaned of dirty, rain water won't spot the windows. The spots generally come from dirty windows. Rain is pure water and once it dries it does not leave any minerals behind. If you spray your windows with a garden hose, you will get spots on the windows from the minerals in the water that is left behind once it dries. Heavy rain may have a different affect as the heavy rain can wash the dirt from above the window down onto the clean windows. This is not likely though.
Patriot Window Cleaning LLC offers a 100% satisfaction guarantee and has a 7 day rain guarantee. After your cleaning and it rains, if the windows get spots on them, we will come back out and spot clean the affected windows free of change.
However, we do understand that some customers would rather reschedule the service to better weather conditions. Just keep in mind that in Texas the weather is very unpredictable and changes constantly. We try our best to keep an eye on the weather to best accommodate our customers.