Every year, around this time of year the same old question arises with outdoor car covers. "Is my car cover leaking?"
The simple answer is No it probably isnt,
Its not leaking, its simple physics due to the time of year, when Damp, Heavy Air passes through breathable fabric, such as a Breathable Car Cover and comes into contact with a cold metal car, forming dew.
This can also be seen, at night or early morning with cars in the street that have moisture on them, yet its not been raining. Same principle. What it means it your car cover is working properly, allowing air to pass both ways through it.
As the temperature rises during the day, this occasional moisture will vent away as the air passes out into the atmosphere. Chances are in Summer and warmer climates you will never see this, but remove car early morning in places like the UK and some parts of Europe and you will.
The only way to prevent this phenomena it to fit a non breathable, plastic cover, which is bad news all round and something we would never recommend. The damp air cant get in, but also, any moisture under the cover, rising up from the ground will get trapped. The car can also sweat during summer months so a breathable cover is ALWAYS the way to go.
The Car Cover Experts - http://www.coveryourcar.co.uk