Forgetting to shut a sunroof on a car can make for a messy situation. Water should never be allowed to enter a car. Leaving a sunroof open in the rain is especially hazardous because a large amount of water can enter the vehicle quickly.
Shut the sunroof as soon as it starts raining. Letting water in can short out electric systems and cause mildew to form in the interior. Shutting the roof right away prevents further damage.
As soon as possible, dry the interior completely using bath and kitchen towels. If it has stopped raining, open all the doors and reopen the sunroof. Use a hair dryer if one is available. Remove the floor mats and allow them to air out for a few hours.
Fix and Clean
The car might have electrical damage, which will need to be fixed by a professional. So that mildew doesn't develop and leave a smell, sprinkle baking soda over the carpet and let it sit overnight before vacuuming it up. Use a steam cleaner to clean the carpet and the upholstery. Use leather cleaner on leather trim and seats.