What Is Extreme Cold?

Extreme cold is generally defined as a prolonged period of excessively cold weather. Extreme cold conditions are often, but not always, part of winter storms.

Why Prepare?

Winter in Massachusetts almost always includes periods of extreme cold weather. Exposure to cold can cause frostbite or hypothermia and has the potential to become life-threatening. Although anyone can suffer from cold-related health issues, some people are at greater risk than others, such as older adults, young children, those who are sick, and those without adequate shelter. To reduce the risks of extreme cold conditions, take the proper safety precautions to protect yourself and your family.


The National Weather Service issues wind chill advisories and warnings to alert the public of potential extreme temperatures. Learn more about the Wind Chill Index and how it is calculated.

Wind Chill Advisory

Wind chill index between -15°F and -24°F for at least three hours.

Wind Chill Warning

Wind chill index below -25°F for at least three hours.

Before Extreme Cold Weather

  • Be Informed by receiving alerts, warnings, and public safety information before, during, and after emergencies. Download the Massachusetts Alerts app.
  • Create and review your family emergency plan.
  • Assemble an emergency kit. Add seasonal supplies to your emergency kit such as extra winter clothing and blankets.
  • Prepare your home for possible emergencies.
    • Know where your electricity, gas, and water switches and valves are located and how to shut them off. You may need to turn off water pipes if your pipes freeze or burst.
    • Maintain heating equipment and chimneys by having them cleaned and inspected every year.
    • Make sure your home is properly insulated.  Caulk and weather-strip doors and windows to keep cold air out. Install storm windows or cover windows with plastic from the inside to provide insulation.
    • Ensure you have sufficient heating fuel and safe backup heating options like fireplaces, wood stoves, or a generator in case you lose electricity.
    • Check that your smoke and carbon monoxide detectors are working and have fresh batteries.
  • Ensure your vehicle is ready for safe winter driving. Keep the gas tank at least half-full and have a Winter Emergency Car Kit in the trunk.

During Extreme Cold Weather

  • Continue to monitor the media for emergency information.
  • Follow instructions from public safety officials.
  • Minimize outdoor activities for the whole family, including pets.
  • Dress in several layers of loose-fitting, lightweight clothing instead of a single heavy layer. Outer garments should be tightly woven and water repellent. Wear a hat, mittens (not gloves), and sturdy waterproof boots to protect your extremities. Cover your mouth with a scarf to protect your lungs.
  • Take recommended safety precautions when using space heaters, a fireplace, or a woodstove to heat your home. Keep a fire extinguisher handy.
  • Make sure emergency generators or secondary heating systems are well ventilated.
  • If you lose heating, move into a single room. Seal off unused areas by stuffing towels against the cracks under the doors, and at night, cover windows with extra blankets or sheets.
  • Wrap pipes in insulation or layers of newspapers covered in plastic to prevent them from freezing. Let a trickle of warm water run from a faucet to keep water moving through your pipes.
  • If your pipes freeze, remove any insulation, pour hot water over them or wrap them with towels soaked in hot water, and completely open all faucets. You can also use a hair dryer, with caution, to thaw pipes. Never use an open flame to thaw pipes.
  • Check with your local authorities or Call 2-1-1 to find warming centers or shelters near you.
  • In the event of a power outage, you may need to take additional precautions or go to an emergency shelter to stay warm.
  • Know the symptoms of and watch out for cold-related illnesses. Call 9-1-1 to report emergencies.
  • Be a good neighbor. Check on family, friends, and neighbors, especially the elderly, those who live alone, those with medical conditions, and those who may need additional assistance.