Best Way To Clear Your Windscreen In Winter, Stay Compliant and Safe

Winter mornings bring a familiar routine for a lot of drivers: start the engine, crank the heat, and head back inside while the car warms up and the windshield clears. It feels harmless, but in many states this habit, known as puffing, can carry a fine, and it is one of the easiest ways to have a vehicle stolen.

This piece looks at what puffing actually is, what the law says about leaving an engine running unattended, the separate rules around driving with a snow or ice covered windshield, and safer ways to get on the road on a cold morning.

What Is Puffing?

Puffing is the term used across much of the country for leaving a vehicle running and unattended while it warms up. The name comes from the visible puffs of exhaust steam a car gives off in cold weather, which is exactly what makes an idling car easy for a thief to spot from across a parking lot or street.

The National Insurance Crime Bureau, an industry body that tracks vehicle theft trends, has warned for years that puffing hands opportunistic thieves an easy target. With the engine running, the doors often unlocked, and the keys already in the ignition, all a thief has to do is get in and drive away.

What Does the Law Say About Leaving Your Engine Running?

There is no single federal law covering this, so the rules depend on where you live. A number of states and cities have specific laws against leaving a vehicle unattended with the engine running, and the penalties vary:

• Texas requires drivers to stop the engine, remove the key, and lock the vehicle before walking away, under the state's Transportation Code.
• Ohio generally bans leaving a vehicle unattended with the engine running under its Revised Code, with a first offense carrying a fine of up to $150.
• Maryland treats it as a ticketable offense, with a fine and a point added to the driver's record.
• Delaware has a specific statute covering unattended motor vehicles.

Other states rely on local ordinances rather than statewide law. Kansas City, for example, has its own rule requiring drivers to stop the engine and lock up before leaving a vehicle unattended, even though Missouri has no statewide law on the practice. Given how much this varies, it is worth checking your own state and city rules rather than assuming the same law applies everywhere.

One consistent exception across most of these laws is the remote starter. A vehicle started remotely, with the doors locked and no key inside, is generally not considered unattended in the same way, since there is nothing for a thief to simply reach in and take.

Why Insurers Care About This Too

Even in places where puffing is not against the law, it can still cost you. If a vehicle is stolen while it was left running and unlocked, some insurers may treat this as negligence on the owner's part, which can affect how a claim is handled. It is worth checking the specific terms of your policy, since coverage decisions vary by insurer and by state.

The Separate Law on Windshields Covered in Snow and Ice

Leaving your engine running to defrost the windshield raises a second legal issue: driving before that ice or snow has actually been cleared. Several states treat this as its own offense, separate from anything to do with puffing.

Pennsylvania and New Jersey both require drivers to clear accumulated snow and ice from exposed surfaces of the vehicle, including the windshield, hood, and roof, before driving. New Jersey's law applies whether or not any snow or ice actually comes loose, with fines starting at $25 per offense and rising sharply, up to $1,000, if flying snow or ice causes injury or damage. Pennsylvania takes a similar approach, and both states impose steeper fines, up to $1,500, if uncleared snow or ice comes off the vehicle and hurts someone or damages property.

Other states without a dedicated snow and ice statute still enforce the same outcome through general obstructed view laws. New York, Connecticut, and several Midwestern states can cite a driver for an obstructed windshield regardless of whether there is a specific snow removal law on the books, since driving without a clear view is treated as unsafe in its own right.

How to Clear Your Windshield Safely

• Stay with the vehicle while it warms up. If you do not have a remote starter, plan to stand by the car rather than heading back inside, so the engine is never running unattended.
• Use a remote starter if you have one. This lets the engine and heater run while the vehicle stays locked, which sidesteps both the theft risk and most unattended vehicle laws.
• Use the defrost settings properly. Front and rear defrosters, along with heated mirrors on some vehicles, will clear the glass faster and more evenly than waiting on cabin heat alone.
• Keep an ice scraper in the vehicle. A manual scraper clears the windshield in a couple of minutes without needing the engine running at all, and is often the fastest option.
• Avoid hot water on cold glass. A sudden temperature change can crack a windshield, so stick to a scraper or the car's own defrost system.
• Consider a windshield cover. Fitting one overnight stops frost from settling in the first place, which cuts down on morning prep significantly.

Protecting Your Vehicle Beyond the Basics

Following the law around unattended vehicles reduces the risk of theft, but it does not eliminate it entirely. Vehicle tracking adds another layer of protection, since a GPS tracker can show a vehicle's location in real time if it is ever taken, which gives law enforcement a far better chance of recovering it quickly. For businesses running a fleet, this matters even more, since a stolen work vehicle does not just represent a financial loss but also lost time and disrupted jobs.

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RAM's GPS fleet tracking gives you real time location data on every vehicle in your fleet, so if one is ever stolen, you and law enforcement have a far better chance of getting it back quickly. Book a demo of our software today.

Common Questions About Puffing and Winter Driving Laws

Is it illegal everywhere to leave my car running unattended?

No. It depends on your state and, in some cases, your city. Several states have specific laws against it, others rely on local ordinances, and a few have no rule at all. Check your local laws if you are unsure.

Does a remote starter get around these laws?

In most places, yes. A vehicle that is locked, has no key inside, and is started remotely is not considered unattended in the same sense as a car with the door unlocked and the key in the ignition.

Will my insurance cover a stolen car if I left it running?

It depends on your insurer and policy. Some may view it as negligence, which can affect a claim, so it is worth checking your policy's specific wording or asking your provider directly.

Is driving with a snow covered windshield actually illegal?

In a number of states, yes, either through a specific snow and ice removal law or through general rules about maintaining a clear view while driving. Fines can range from small amounts for the windshield alone up to much larger penalties if uncleared snow or ice causes an accident.

What is the safest way to defrost a windshield?

Stay with the vehicle, use its defrost settings and a scraper rather than hot water, and consider a windshield cover to reduce the amount of ice that builds up overnight in the first place.