Few road trips avoid traffic jams, but when drivers encounter intense weather, an inconvenience can turn into an emergency. This week, travelers taking Interstate 95 through Fredericksburg, Va., ran into a winter storm that trapped hundreds on the road overnight in below-freezing temperatures.

Many motorists — including Sen. Tim Kaine (D-Va.) — were forced to improvise, turning their cars on and off to save fuel, taking short naps to recharge, rationing food and water, and sharing sustenance with fellow drivers and passengers. The interstate reopened Tuesday, and elected officials began calling for a large-scale investigation into the meltdown.

With months of winter ahead, By The Way spoke to experts about how to prepare for the worst ahead of time and what to do if your car gets stuck in a scary storm.

What to do before you take the wheel

First, check the forecast, look for any weather advisories, and heed warnings not to travel.

Lauren Opett, the director of communications for the Virginia Department of Emergency Management, recommended “mapping out your trip and then looking at the weather not only where you’re at currently, but where you’re going and then along the route.”

Make sure to properly maintain your car by checking fluid levels, the condition of wiper blades, tire pressure and tread before hitting the road.

If you do drive in a winter storm, be extra careful on the road. Michael de Vulpillieres, a spokesperson for the American Red Cross, said drivers should avoid following other cars too closely and refrain from using cruise control to maintain total command of their vehicles. He also noted that bridges and overpasses freeze over before other roadways.

“Exercising extreme caution if you do have to drive in the snow is really critical,” de Vulpillieres said.

Opett added that drivers should pay special attention to emergency vehicles and snowplows, making sure to move over and slow down when they pass.

What you should always have on hand

Experts advise you should keep a few essentials in your car at all times, including a portable phone charger, a first-aid kit, a flashlight with a backup set of batteries, jumper cables and road flares.

Stow some snacks, such as granola bars, and bottled water, and — if you’re traveling with children or pets — keep food and supplies for them, too.

“But also remember, if you’re creating this kit and you’re just going to leave it in your car, those items do expire,” said David Bennett, repair systems manager at AAA. He said you should check those items frequently and replace them as needed.

What to pack when storms are in the forecast

During winter weather, it’s crucial to dress appropriately. Wear warm clothing and layers, including a coat, hat and gloves, experts said. Carry a blanket or two, and keep seasonal tools such as ice scrapers and snow brushes in your car.

“The big thing that you’re looking to do is to keep your windows clean and have good visibility,” Bennett said.

Opett also recommended sand, salt and non-clumping cat litter, which can help with traction.

How to find help

If you’re having an emergency, 911 should be your first call, Bennett said. Otherwise, if you’re a AAA member and find yourself in need of assistance, reach out to them. You can also contact highway patrol.

Opett urged drivers to remember that responders may be delayed themselves, underscoring the need for personal preparedness. “It could be due to a number of reasons like call volume, access issues, which we saw earlier this week, or just weather conditions that limit their ability to respond quickly.”

While it’s generally safest to stay in your car if you’re stranded, there are other ways to signal that you need help to those nearby.

You can display a brightly colored cloth on your radio antenna, de Vulpillieres said, to signal that you’re in trouble, and raise the hood once it stops snowing. You can also place reflective triangles behind your car to indicate that it has broken down, Bennett added.

It can be dangerous to leave your car in search of assistance unless help is visible within 100 yards, de Vulpillieres warned. “It’s easy to become disoriented in a blowing storm, in a blizzard, so you want to make sure that you’re not moving too far away from your car,” he said.

What to do if you run out of gas

Turn the car on and off as long as you’re stuck, but don’t let it run too long. This conserves fuel, and letting the engine run indefinitely is “not that great for the vehicle,” Bennett said. AAA recommends running the car for five to 10 minutes to warm it up, and then shutting it off for 30 to 45 minutes before starting it up again.

If you do run out of gas, Bennett added, you may have to get out and push to get the car out of the main roadway, either over to the shoulder or onto the median. Then, until you can get help, put those blankets and coats to good use, as there is a risk of hypothermia.

What to do if your car gets flooded underwater

Melting snow or heavy rain can cause flood damage to cars. If you believe water is getting near the engine or passenger cabin, Bennett cautioned, drivers should turn the engine off to avoid hydrolock, which causes it to quit running. “Don’t drive through puddles, because you don’t know how deep those puddles are,” he added.

If the car is flooding, you should get out as soon and as safely as possible. If you lose power and the need arises, you can use tools designed to break the glass and exit through a window.