Winter storms can range from moderate snow over a few hours to a blizzard with blinding, wind-driven snow that lasts for several days.
Many winter storms are accompanied by dangerously low temperatures and sometimes by strong winds, icing, sleet, and freezing rain. Some winter storms may affect the entire state or be geographically local to the southeastern coastal plains.
Sleet is formed when raindrops freeze to form an ice pellet before reaching the ground where it will bounce but does not usually stick to objects. However, sleet can accumulate, like snow, and create hazardous driving conditions.
Freezing rain is rain that falls to the ground where the temperature is below freezing and allows the rain to create a glaze of ice on roadways. An ice storm occurs when freezing rain falls and freezes upon impact with objects and creates hazards for power lines, roads, and trees.
A freeze event is marked by low temperatures below the freezing point (32° Fahrenheit).
Freeze events are particularly dangerous. Exposure to freezing events can result in wind chill, hypothermia, and frostbite. More than 50% of the cold injuries occur in people over the age of 60 and more than 75% are males. Around 20% of cold injuries occur in the home.
In the south, near-freezing temperatures are considered extreme cold. Freezing temperatures can be a danger to agricultural production especially when freezes occur late in the season and persist over an extended period of time.
Heavy Snow Event
A heavy snow event is defined by the National Weather Service as an accumulation of 4 or more inches in 12 hours or less. A blizzard is the most severe form of a winter storm. It combines low temperatures, heavy snow, and winds of 35 miles per hour or more, which reduces visibility to a quarter-mile or less for at least three hours. Winter storms are often accompanied by sleet, freezing rain, or ice storm. Such freeze events are particularly hazardous as they create treacherous surfaces
Winter Storm Safety
Before Winter Storms and Extreme Cold
Get ready for a winter storm:
- Restock or update your emergency kit. Always keep at least a seven-day supply of non-perishable food in your home and a gallon of water per person per day.
- Add the following supplies to your emergency kit:
- Rock salt or more environmentally safe products to melt ice on walkways. Visit the Environmental Protection Agency for a full list of suggested products.
- Sand to make traction better.
- Snow shovels and other snow removal equipment.
- Have plenty of heating fuel. Store a good supply of dry, seasoned wood for your fireplace or wood-burning stove.
- Have enough clothing and blankets to keep you warm.
- Make a family communications plan. Your family may not be together when disaster strikes, so know how you will get in touch with one another, how you will get back together, and what you will do in case of an emergency.
- Listen to a NOAA weather radio or other local news channels for important information from the National Weather Service (NWS). Know when weather changes.
- Try not to travel. If travel is needed, keep a disaster supplies kit in your vehicle.
- Bring pets inside during winter weather. Move other animals or livestock to sheltered areas with non-frozen drinking water.
- Make sure you have a good amount of heating fuel. Regular fuel sources may be cut off.
- If you have a fireplace, store a good supply of dry, seasoned wood.
- NEVER USE A CHARCOAL GRILL OR CAMP STOVE INDOORS FOR EITHER COOKING OR HEATING. THE FUMES CAN BE TOXIC.
Winterize your home:
- Winterize your home to by insulating walls and attics, caulking and weather-stripping doors and windows. Install storm windows or cover windows with plastic.
- Winterize your house, barn, shed or any other structure that may give shelter for your family, neighbors, livestock or equipment.
- Clear rain gutters. Fix roof leaks and cut away tree branches that could fall on a house or other structure during a storm.
- Keep heating equipment and chimneys by having them cleaned and checked every year.
- Insulate pipes and allow faucets to drip a little during cold weather to keep from freezing. Running water, even at a trickle, helps keep pipes from freezing.
- All fuel-burning equipment should be vented to the outside and kept clear.
- Keep fire extinguishers on hand. Make sure everyone in your house knows how to use them. House fires can be an extra risk, as more people turn to alternate heating sources without taking the needed safety precautions.
- Learn how to shut off water valves in case a pipe bursts.
- Insulate your home by installing storm windows or covering windows with plastic from the inside to keep cold air out.
- Hire a skilled contractor to check the structural ability of the roof to hold unusually heavy weight from the accumulation of snow - or water, if drains on flat roofs do not work.
Winterize Your Vehicle:
Check or have a mechanic check the following items on your car:
- Antifreeze levels - ensure they are sufficient to avoid freezing.
- Battery and ignition system - should be in top condition and battery terminals should be clean.
- Brakes - check for wear and fluid levels.
- Exhaust system - check for leaks and crimped pipes and repair or replace as necessary. Carbon monoxide is deadly and usually gives no warning.
- Fuel and air filters - replace and keep water out of the system by using additives and maintaining a full tank of gas. A full tank will keep the fuel line from freezing.
- Heater and defroster - ensure they work properly.
- Lights and flashing hazard lights - check for serviceability.
- Oil - check for level and weight. Heavier oils congeal more at low temperatures and do not lubricate as well.
- Thermostat - ensure it works properly.
- Windshield wiper equipment - repair any problems and maintain proper washer fluid level.
- Install good winter tires - Make sure the tires have adequate tread. All-weather radials are usually adequate for most winter conditions. However, some jurisdictions require that to drive on their roads, vehicles must be equipped with chains or snow tires with studs.
During Winter Storms and Extreme Cold
- Stay indoors during the storm.
- Walk carefully on snowy, icy, walkways.
- Try not to do too much when shoveling snow. Doing too much, or overexertion, can bring on a heart attack—a major cause of death in the winter. If you must shovel snow, stretch before going outside.
- Keep dry. Change wet clothing often to stop a loss of body heat. Wet clothing loses all of its insulating value and spreads heat rapidly.
- Wear a lot of layers of thin clothing to stay warmer. You can easily take off layers to stay comfortable. Wear a hat. Most body heat is lost through the top of the head. Cover your mouth with scarves to protect lungs from directly breathing in extremely cold air.
- Watch for signs of frostbite. These include loss of feeling and white or pale look of fingers, toes, ear lobes, and the tip of the nose. If you see these symptoms, get medical help.
- Watch for signs of hypothermia. These include uncontrollable shivering, memory loss, disorientation, incoherence, slurred speech, drowsiness and visible exhaustion. If you see these symptoms, get the person to a warm place. Take off wet clothing. Warm the center of the body first. Give the person warm, non-alcoholic drinks if he/she is conscious. Get medical help as soon as you can.
- Drive only if it is absolutely necessary. See tips below.
- If the pipes freeze, take off any insulation or layers of newspapers. Wrap pipes in rags. Completely open all faucets. Pour hot water over the pipes, starting where they were most open to the cold or where the cold was most likely to enter.
- Keep the area aired when using kerosene heaters as to not build up toxic fumes. Refuel kerosene heaters outside. Keep them at least three feet from flammable objects.
- Conserve fuel, if necessary, by keeping your home cooler than normal. For the time being close off heat to some rooms.
- Keep fire extinguishers on hand. Make sure your family knows how to use them. Know fire prevention rules.
- If you will be going away during cold weather, leave the heat on in your home. Set the temperature no lower than 55ºF.
Driving in Winter Weather
If you must travel, the North Carolina Highway Patrol gives the warnings below.
- Reduce your speed. Driving at the regular speed limit will lower your chances to control the car if you begin to slide.
- Leave plenty of room between you and other vehicles.
- Bridges and overpasses collect ice first. Approach them with a lot of caution. Do not push your brakes while on the bridge.
- If you do begin to slide, take your foot off the gas. Turn the steering wheel IN THE DIRECTION OF THE SLIDE. Do NOT push the brakes as that will cause further loss of control of the car.
If you become trapped in your car:
- Pull off the highway. Stay calm and stay inside your vehicle. At night, turn on the inside dome light, so work and rescue crews can see you.
- Set your directional lights to "flashing" and hang a cloth or distress flag from the radio aerial or window.
- In a rural or wilderness area, put a large cloth over the snow to get rescue crews who may be looking at the area by airplane to see you.
- Do not go out on foot unless you can see a building close by where you know you can take shelter.
- If you run the engine to keep warm, open a window a little bit for air. This will keep you safe from possible carbon monoxide poisoning. When you can, clear away snow from the exhaust pipe.
- Exercise to keep body heat, but try not to do too much. In extreme cold, use road maps, seat covers and floor mats for insulation. Huddle with passengers and use your coat as a blanket.
- Never let everyone in the car sleep at once. One person should stay awake to look out for rescue crews.
- Be careful not to use battery power. Balance electrical energy needs - the use of lights, heat and radio - with your supply.
After Winter Storms and Extreme Cold
- Go to the selected public shelter for your area, if your home loses power or heat during periods of extreme cold.
- Protect yourself from frostbite and hypothermia by wearing warm, loose-fitting, lightweight clothing in many layers. Stay indoors, if possible.
Learn From Every Storm
Restock your emergency supplies to be ready in case another storm hits.
- Assess how well your supplies and family plan worked. What could you have done better?
- Take a few minutes to improve your family plan and supplies before the next winter storm hits.
- Talk to your neighbors and colleagues about their experiences and share tips with each other.
Freezing RainRain that freezes when it hits the ground, creating a coating of ice on roads, walkways, trees and power lines.
SleetRain that turns to ice pellets before reaching the ground. Sleet also causes moisture on roads to freeze and become slippery.
Wind ChillWindchill is the temperature it “feels like” when you are outside. The NWS provides a Windchill Chart to show the difference between air temperature and the perceived temperature and the amount of time until frostbite occurs. For more information, visit: http://www.nws.noaa.gov/om/winter/windchill.shtml.
Winter Weather AdvisoryWinter weather conditions are expected to cause significant inconveniences and may be hazardous. When caution is used, these situations should not be life threatening. The NWS issues a winter weather advisory when conditions are expected to cause significant inconveniences that may be hazardous. If caution is used, these situations should not be life-threatening.
Winter Storm Watch
A winter storm is possible in your area. Tune in to NOAA Weather Radio, commercial radio, or television for more information. The NWS issues a winter storm watch when severe winter conditions, such as heavy snow and/or ice, may affect your area but the location and timing are still uncertain. A winter storm watch is issued 12 to 36 hours in advance of a potential severe storm. Tune in to NOAA Weather Radio, local radio, TV, or other news sources for more information. Monitor alerts, check your emergency supplies, and gather any items you may need if you lose power.
Winter Storm Warning
A winter storm is occurring or will soon occur in your area.
Blizzard WarningSustained winds or frequent gusts to 35 miles per hour or greater and considerable amounts of falling or blowing snow (reducing visibility to less than a quarter mile) are expected to prevail for a period of three hours or longer.
Frost/Freeze WarningBelow freezing temperatures are expected.
Want to learn more about winter weather and extreme cold? Visit these sites for more information:
- National Weather Service: Winter Weather Safety
- Ready.gov: Winter Weather
- ReadyNC.org: Winter Weather
- CDC: Winter Weather
- CDC: Extreme Cold Guide (PDF, 3MB)
- NOAA: Winter Storms, The Deceptive Killers (PDF, 1.2MB)