An unusually snowy winter like this one may seem ideal for the car wash business, given all the salt-streaked cars it produces.

But local car wash owners say the weather hasn't been much of an advantage.

Some snow definitely helps business, explained Noah Levine, who owns Rapid Car Wash on Colman Street in New London, but there's a limit.

This winter, "there's just too much snow," he said Sunday. "Too much of a good thing."

"Customers are going to want to have three or four days of a clean car," said Levine. If bad weather is predicted and "they think it's going to last one day or until they get to the traffic light," drivers figure a wash isn't worth the cost.

Herbert Nyberg, who owns Colonial Car Wash in Norwich and in Niantic, agreed with Levine's assessment.

The day of a snowstorm and several days after are bad for business, said Nyberg, but on the third or fourth day the cars start to roll in.

He said the clustered snowstorms of early 2014 have impacted the demand for car washes because by the fourth day after a storm it's often snowing again.

February is usually one of the busier months, but Nyberg had to close because of bad weather several times this month, which has hurt his revenue. Adding to the problem, is that the bitter cold has also kept customers away even when it doesn't snow.

On a warm day after a snowfall, the line of cars at Rapid Car Wash sometimes stretches all the way to the street, said Levine's wife, Linda. But although they might get 500 customers on a day like that, it's often followed by a few days in which only the most loyal customers come in, so it averages out, she said.

Linda Levine said there are some people who will visit the car wash before a storm or even while it's snowing, but they are unusual - "faithful diehards," as she described them.

Stacie Girardin of Groton was one of dozens of customers who packed the Rapid Car Wash parking lot on Sunday afternoon, taking advantage of the sunnier weather to clean and vacuum her car.

Girardin said it was the first wash she'd given the minivan all winter, because there was no point in cleaning frequently with the continuous bad weather.

"I feel like I wash my car less" in the winter, agreed fellow customer Blaze Wiersch of New London, who said she will usually hold off if she knows more snow is coming.

But both Levine and Nyberg encourage people to wash during the winter, because the salt and other chemicals can damage vehicles.

Salt, which dissolves easily in water, is not difficult to rinse off cars, explained Levine.

"Cleaning the car in the winter is probably easier than doing it in the springtime," when bugs and pollen stick to the vehicle, he said.

But if salt is left sitting on the vehicle for days on end, cautioned Nyberg, it could mar the finish, so drivers should clean the car regularly. He said salt and dirt could also accelerate rusting on brake lines and other car components.

Additionally, the magnesium chloride the state uses in combination with salt can corrode the undercarriage of cars, so both Nyberg and Levine suggest getting an underwash to remove it.

A report on the Connecticut General Assembly's website acknowledges that magnesium chloride, which is only used when the temperature is below 25 degrees, can corrode vehicles, but said the chemical increases road safety.

The Department of Transportation encourages drivers to wash their vehicles, including the undercarriages, regularly during the winter, according to the report.

k.catalfamo@theday.com