In January 2019, the Arctic polar vortex made headlines as it plunged the Midwestern U.S. into a deep freeze that lasted several days. The record-setting low temperatures were linked to as many as 21 deaths in the region, and during the worst, the U.S. Postal Service canceled mail deliveries in several areas. For many, it was the first time they’d heard of a polar vortex, a term known better to meteorologists and scientists. What is a polar vortex and why is it so dangerous? Here's what you should know.
What Is a Polar Vortex?
A polar vortex is a large area of low pressure and cold air that exists in both of the Earth’s poles. The Arctic polar vortex, also referred to as the Northern Hemisphere polar vortex, is a band of strong and cold winds that surrounds the North Pole 10 to 30 miles above the surface. Similarly, the Southern Hemisphere's polar vortex covers the South Pole, but it is larger, colder, and longer-lasting than the Arctic vortex.
How the Polar Vortex Affects Our Weather
Miles below the polar vortex, at 5 to 9 miles above the surface of the Earth, is another strong band of winds — the polar jet stream. These winds typically travel west to east around the pole in a stable pattern. Most of the time, the two bands of wind don’t interact with each other, but occasionally, the polar vortex weakens and begins to spread out. When that happens — about every two years, according to NOAA stratosphere expert Amy Butler — the polar jet stream starts to get wavy, developing deep valleys and ridges that sometimes stall over a region for days at a time. Combined with other conditions, it can spark an outbreak of extreme cold weather in the Northern Hemisphere.
Why Is the Polar Vortex Dangerous?
In and of itself, the polar vortex isn’t dangerous, but extended periods of extreme cold can be very dangerous if you’re not prepared for them. The addition of high winds that accompany weather driven by a polar vortex makes the low temperatures even more hazardous. Being prepared for cold-weather events can help you keep your family and yourself safe and healthy when the polar vortex gets knocked off-kilter.
Cold Weather Safety Tips
The safest place to be when the temperatures dip into freezing territory is indoors, but that’s not always possible. Here’s how to prepare and plan for winter cold, indoors and out:
- Plan ahead. Before winter sets in, winterize your home, paying special attention to rooms used by infants, children, or older adults.
- Prepare your car for winter. Have the radiator checked and add antifreeze if necessary. Replace your windshield wiper fluid with one made for winter. Check your tires, or replace them with snow tires. Keep the gas tank as near to full as possible. Put together a car emergency kit and keep it in your car.
- Monitor the weather conditions. An AcuRite Olympus Series® weather station can keep you informed of temperature, humidity, wind speed and direction, and much more. You can even customize your weather station to provide real-time alerts and notifications.
- Avoid driving in hazardous conditions. If you live in an area where winter storms are common, learn what to do if you’re forced to drive in winter storms.
If you go outdoors, the Centers for Disease Control and Prevention offers these tips and suggestions:
- Dress warmly. Wear a hat, a scarf, or a knit mask that covers your nose and mouth; a coat with sleeves that are snug at the wrist; mittens; water-resistant boots; and several layers of loose-fitting clothing.
- Understand the difference between humid cold and dry cold and how to best prepare for either.
- Stay dry. Wet clothing will speed up heat loss, increasing the risk of hypothermia.
- Understand wind chill. The wind not only makes it feel much colder, it actually draws heat away from your body faster.
- If you’re planning outdoor recreation, make sure someone knows what your plans are. Keep your skin covered as much as possible. Bring along extra dry clothing, a two-way radio, waterproof matches, and paraffin fire starters.
In addition, a portable weather device can help you monitor for conditions such as extremely low temperatures or strong wind gusts while you’re out, giving you time to get to safety or prepare to shelter.
If You Get Stranded in the Cold
If you get stranded in freezing weather, it’s usually best to stay with your vehicle or shelter. Moving around increases the risk of exposure and may make it harder for help to find you. These steps will also increase your safety:
- Tie a brightly colored scarf or item of clothing to your car antenna. If you’re not with your vehicle — if, for example, you’re hiking or camping — increase visibility with something brightly colored.
- Move anything you need from your trunk to the passenger area to decrease the number of times you’ll have to exit the vehicle.
- Wrap your entire body in extra clothing or blankets.
- Stay awake. You’re less vulnerable to hypothermia and other cold-related health problems when you’re awake.
- Run the motor and heater about 10 minutes per hour, with one window cracked slightly for air. Be sure the exhaust pipe isn’t blocked with snow.
- If you’re stranded with other people, huddle together to conserve warmth.
- Move your arms and legs to increase circulation and body heat.
Winter Weather and the Polar Vortex
Winter and cold weather go together, with or without help from the polar vortex. Being prepared for the cold with a home weather station can help you and your entire household get through the winter cold safely and in good health.