Heavy snow can immobilize a region and paralyze a city, stranding commuters, closing airports, stopping the flow of supplies, and disrupting emergency and medical services. Accumulations of snow can cause roofs to collapse and knock down trees and powerlines. Homes and farms may be isolated for days and unprotected livestock may be lost. In the mountains, heavy snow can lead to avalanches. The cost of snow removal, repairing damages, and the loss of business can have severe economic impacts on cities and towns.
BLIZZARD: Winds of 35 mph or more with snow and blowing snow reducing visibility to less than ¼ mile for 3 hours or more.
BLOWING SNOW: Wind-driven snow that reduces visibility. Blowing snow may be falling snow and/or snow on the ground picked up by the wind.
SNOW SQUALLS: Brief, intense snow showers accompanied by strong, gusty winds. Accumulation may be signifi cant.
SNOW SHOWERS: Snow falling at varying intensities for brief periods of time. Some accumulation is possible.
SNOW FLURRIES: Light snow falling for short durations with little or no accumulation.
An avalanche is a mass of tumbling snow. More than 80 percent of midwinter avalanches are triggered by a rapid accumulation of snow, and 90 percent of those occur within 24 hours of snowfall. An avalanche may reach a mass of a million tons and travel at speeds up to 200 mph.
Heavy accumulations of ice can bring down trees and topple utility poles and communication towers. Ice can disrupt communications and power for days while utility companies repair extensive damage. Even small accumulations of ice can be extremely dangerous to motorists and pedestrians. Bridges and overpasses are particularly dangerous because they freeze before other surfaces.
Winter storms can generate coastal flooding, ice jams and snow melt, resulting in significant damage and loss of life.
COASTAL FLOODS: Winds generated from intense winter storms can cause widespread tidal flooding and severe beach erosion along coastal areas.
ICE JAMS: Long cold spells can cause rivers and lakes to freeze. A rise in the water level or a thaw breaks the ice into large chunks which become jammed at man made and natural obstructions. Ice jams can act as a dam, resulting in severe flooding.
SNOW MELT: Sudden thaw of a heavy snow pack often leads to flooding.
Exposure to cold can cause frostbite or hypothermia and become life-threatening. Infants and elderly people are most susceptible. What constitutes extreme cold varies in different parts of the country. In the South, near freezing temperatures are considered extreme cold. Freezing temperatures can cause severe damage to citrus fruit crops and other vegetation. Pipes may freeze and burst in homes that are poorly insulated or without heat. In the North, extreme cold means temperatures well below zero.
Wind Chill is not the actual temperature but rather how wind and cold feel on exposed skin. As the wind increases, heat is carried away from the body at an accelerated rate, driving down the body temperature. Animals are also affected by wind chill; however, cars, plants and other objects are not.
Frostbite is damage to body tissue caused by extreme cold. A wind chill of -20° Fahrenheit (F) will cause frostbite in just 30 minutes. Frostbite causes a loss of feeling and a white or pale appearance in extremities, such as fingers, toes, ear lobes or the tip of the nose. If symptoms are detected, get medical help immediately! If you must wait for help, slowly rewarm affected areas. However, if the person is also showing signs of hypothermia, warm the body core before the extremities.
Hypothermia is a condition brought on when the body temperature drops to less than 95°F. It can kill. For those who survive, there are likely to be lasting kidney, liver and pancreas problems. Warning signs include uncontrollable shivering, memory loss, disorientation, incoherence, slurred speech, drowsiness and apparent exhaustion. Take the person’s temperature. If below 95°F, seek medical care immediately!
If Medical Care is Not Available, warm the person slowly, starting with the body core. Warming the arms and legs fi rst drives cold blood toward the heart and can lead to heart failure. If necessary, use your body heat to help. Get the person into dry clothing and wrap in a warm blanket covering the head and neck. Do not give the person alcohol, drugs, coffee or any hot beverage or food. Warm broth is the first food to offer.
There are many ways for winter storms to form; however, all have three key components.
COLD AIR: For snow and ice to form, the temperature must be below freezing in the clouds and near the ground.
MOISTURE: Water evaporating from bodies of water, such as a large lake or the ocean, is an excellent source of moisture.
LIFT: Lift causes moisture to rise and form clouds and precipitation. An example of lift is warm air colliding with cold air and being forced to rise. Another example of lift is air fl owing up a mountain side.
KEEP AHEAD OF THE STORM by listening to NOAA Weather Radio, commercial radio and television for the latest winter storm warnings, watches and advisories
NOAA Weather Radio is the best means to receive warnings from the National Weather Service. The National Weather Service continuously broadcasts warnings and forecasts that can be received by NOAA Weather Radios, which are sold in many stores. The average range is 40 miles, depending on topography. Purchase a radio that has a battery back-up and a Specifi c Area Message Encoder feature, which automatically alerts you when a watch or warning is issued for your county or parish.
The National Weather Service issues outlooks, watches, warnings and advisories for all winter weather hazards. Here’s what they mean and what to do. Use the information below to make an informed decision on your risk and what actions should be taken. Remember to listen to your local offi cials’ recommendations and to NOAA Weather Radio for the latest winter storm information.
OUTLOOK: Winter storm conditions are possible in the next 2-5 days. Stay tuned to local media for updates.
WATCH: Winter storm conditions are possible within the next 36-48 hours. Prepare now!
WARNING: Life-threatening severe winter conditions have begun or will begin within 24 hours. Act now!
ADVISORY: Winter weather conditions are expected to cause signifi cant inconveniences and may be hazardous. If you are cautious, these situations should not be life threatening.
Primary concerns are loss of heat, power and telephone service and a shortage of supplies if storm conditions continue for more than a day.
Have available:
Plan your travel and check the latest weather reports to avoid the storm!
Fully check and winterize your vehicle before the winter season begins.
Carry a WINTER STORM SURVIVAL KIT:
Keep your gas tank near full to avoid ice in the tank and fuel lines.
Avoid traveling alone.
Let someone know your timetable and primary and alternate routes.
Move animals to sheltered areas.
Shelter belts, properly laid out and oriented, are better protection for cattle than confi ning shelters, such as sheds.
Haul extra feed to nearby feeding areas.
Have water available. Most animals die from dehydration in winter storms.
Make sure pets have plenty of food, water and shelter.
Wear loose, lightweight, warm clothes in layers. Trapped air insulates. Remove layers to avoid perspiration and sub sequent chill. Outer garments should be tightly woven, water repellent, and hooded. Wear a hat. Half your body heat loss can be from the head. Cover your mouth to protect your lungs from extreme cold. Mittens, snug at the wrist, are better than gloves. Try to stay dry.
Find shelter:
No shelter:
Melt snow for drinking water:
Stay in vehicle:
Be visible to rescuers:
Exercise:
Stay inside:
No heat:
such as shoveling heavy snow, pushing a car or walking in deep snow. The strain from the cold and the hard labor may cause a heart attack. Sweating could lead to a chill and hypothermia. Take Red Cross Cardiopulminary Rescue (CPR) and Automated External Defi brillator (AED) training so you can respond quickly to an emergency
Prepare for hazards that affect your area with a Family Disaster Plan. Where will your family be when disaster strikes? They could be anywhere at work, at school or in the car. How will you fi nd each other? Will you know if your children are safe? Disasters may force you to evacuate your neighborhood or confi ne you to your home. What would you do if basic services – water, gas, electricity or telephones – were cut off?
Contact your local National Weather Service office, American Red Cross chapter or emergency management office for a copy of “Your Family Disaster Plan” (L-191/ARC4466).
For More Information:
Contact your local National Weather Service (NWS) office, American Red Cross chapter or local emergency management agency for more weather-related brochures.
You can find more information on flash flooding in the Floods… The Awesome Power brochure. Contact your local Red Cross chapter or NWS office for copies. You can download a copy at this NWS Web site http://www.nws.noaa.gov/om/water/ahps/pdfs/Floodsbrochure_02_06.pdf. To find additional materials on winter safety, try the following Web sites:
NWS: www.nws.noaa.gov
FEMA: www.fema.gov
Red Cross: www.redcross.org
Publication #: ARC 4467 June 2008 NOAA/PA 200160
Disclaimer and Reproduction Information: Information in NASD does not represent NIOSH policy. Information included in NASD appears by permission of the author and/or copyright holder. More