It's better to wash the car on a non-windy, cool cloudy day. Do not wash the car especially under the strong sun light, on a windy day, or when the car body is heated. If you wash the car when the surfaces are hot, shampoo dries quickly and it may cause stains. It also makes it difficult to apply waxes and coating agents evenly.
Therefore, we recommend you wash your car in the morning during the summer or on a sunny day during other seasons. However, remember 2 things: 1. Be sure to wash the car rinsing part by part in order to prevent car shampoo from drying. 2. Do not apply waxes to hot surfaces.
In addition, it's better not to wash the car in a windy day, because flying sand and dust will adhere to the washed car surfaces and it will cause scratches when you wipe with a towel or apply a wax.