winter storms...
the Deceptive Killers
A
GUIDE TO SURVIVAL
U.S.
DEPARTMENT OF COMMERCE
National
Oceanic and Atmospheric Administration National Weather Service Warning and
Forecast Branch November 1991
Sometimes winter storms are accompanied by strong winds creating blizzard conditions with blinding wind-driven snow, severe drifting, and dangerous wind chill. Strong winds with these intense storms and cold fronts can knock down trees, utility poles, and power lines. Storms near the coast can cause coastal flooding and beach erosion as well as sink ships at sea. In the West and Alaska, winds descending off the mountains can gust to 100 mph or more damaging roofs and other structures.
Extreme cold often accompanies a winter storm or is left in its wake. Prolonged exposure to the cold can cause frostbite or hypothermia and become life-threatening. Infants and elderly people are most susceptible. What constitutes extreme cold and its effect varies across different areas of the United States. In areas unaccustomed to winter weather, 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, below zero temperatures may be considered as "extreme cold." Long cold spells can cause rivers to freeze, disrupting shipping. Ice jams may form and lead to flooding.
Heavy accumulations of
ice can bring down trees, electrical wires, telephone poles and lines, and
communication towers. Communications and power can be disrupted for days while
utility companies work to repair the extensive damage. Even small accumulations
of ice may cause extreme hazards to motorists and pedestrians.
Heavy Snow Storms
Heavy snow can immobilize a region and paralyze a city, stranding commuters, stopping the flow of supplies, and disrupting emergency and medical services. Accumulations of snow can collapse buildings and knock down trees and power lines. In rural areas, 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 loss of business can have large economic impacts on cities and towns.
FLURRIES - Light snow falling for short durations. No accumulation or light dusting is all that is expected.
SHOWERS - Snow falling
at varying intensities for brief periods of time. Some accumulation is
possible.
SQUALLS - Brief, intense snow showers
accompanied by strong, gusty winds. Accumulation may be significant. Snow
squalls are best known in the Great Lakes region.
BLOWING SNOW - Wind-driven snow that
reduces visibility and causes significant drifting. Blowing snow may be snow
that is falling and/or loose snow on the ground picked up by the wind.
BLIZZARD - Winds over 35 mph with snow
and blowing snow reducing visibility to near zero.
Rain drops that
freeze into ice pellets before reaching the ground. Sleet usually bounces when
hitting a surface and does not stick to objects. However, it can accumulate
like snow and cause a hazard to motorists.
Rain that falls
onto a surface with a temperature below freezing. This causes it to freeze to
surfaces, such as trees, cars, and roads, forming a coating or glaze of ice.
Even small accumulations of ice can cause a significant hazard.
From
the Mid-Atlantic Coast to New England...The classic storm is called a Nor'easter. A low
pressure area off the Carolina coast strengthens and moves north. Wind-driven
waves batter the coast from Virginia to Maine, causing flooding and severe
beach erosion. The storm taps the Atlantic's moisture-supply and dumps heavy
snow over a densely populated region. The snow and wind may combine into
blizzard conditions and form deep drifts paralyzing the region. Ice storms are
also a problem. Mountains, such as the Appalachians, act as a barrier to cold
air trapping it in the valleys and adjacent low elevations. Warm air and
moisture moves over the cold, trapped air. Rain falls from the warm layer onto
a cold surface below becoming ice.
Along
the Gulf Coast and Southeast...This
region is generally unaccustomed to snow, ice, and freezing temperatures. Once
in a while, cold air penetrates south across Texas and Florida, into the Gulf
of Mexico. Temperatures fall below freezing killing tender vegetation, such as
flowering plants and the citrus fruit crop. Wet snow and ice rapidly accumulate
on trees with leaves, causing the branches to snap under the load. Motorists
are generally unaccustomed to driving on slick roads and traffic accidents
increase. Some buildings are poorly insulated or lack heat altogether. Local
municipalities may not have available snow removal equipment or treatments,
such as sand or salt, for icy roads.
In
the Midwest and Plains...Storms
tend to develop over southeast Colorado in the lee of the Rockies. These storms
move east or northeast and use both the southward plunge of cold air from
Canada and the northward flow of moisture from the Gulf of Mexico to produce
heavy snow and sometimes blizzard conditions. Other storms affecting the
Midwest and Plains intensify in the lee of the Canadian Rockies and move
southeast. Arctic air is drawn from the north and moves south across the Plains
and Great Lakes. Wind and cold sometimes combine to cause wind chill
temperatures as low as 70F below zero. The wind crosses the lakes, tapping its
moisture and forming snow squalls and narrow heavy snow bands. This is called
"lake-effect snow."
From the
Rockies to the West Coast...Strong
storms crossing the North Pacific sometimes slam into the coast from California
to Washington. The vast Pacific provides an unlimited source of moisture for
the storm. If cold enough, snow falls over Washington and Oregon and sometimes
even in California. As the moisture rises into the mountains, heavy snow closes
the mountain passes and can cause avalanches. The cold air from the north has
to filter through mountain canyons into the basins and valleys to the south. If
the cold air is deep enough, it can spill over the mountain ridge. As the air
funnels through canyons and over ridges, wind speeds can reach 100 mph,
damaging roofs and taking down power and telephone lines. Combining these winds
with snow results in a blizzard.
In
Alaska...Wind-driven waves
from intense storms crossing the Bering Sea produce coastal flooding and can
drive large chunks of sea ice inland destroying buildings near the shore. High
winds, especially across Alaska's Arctic coast, can combine with loose snow to
produce a blinding blizzard and wind chill temperatures to 90F below zero!
Extreme cold (-40F to -60F) and ice fog may last a week at a time. Heavy snow
can impact the interior and is common along the southern coast. With only brief
glimpses of the winter sun across the southern horizon, the snow accumulates
through the winter months. In the mountains, it builds glaciers, but the heavy
snow accumulations can also cause avalanches or collapse roofs of buildings. A
quick thaw means certain flooding. Ice jams on rivers can also cause
substantial flooding.
Winter
Storm Facts:
What Makes a Winter Storm?
COLD AIR:
below freezing temperatures in the clouds and near the ground are necessary to make snow and/or ice.
MOISTURE:
to form clouds and precipitation. Air blowing across a body of
water, such as a large lake or the ocean, is an excellent source of moisture.
LIFT:
something to raise the moist air to form the clouds and cause
precipitation. An example of lift is warm air colliding
with cold air and being forced to rise over the cold dome. The boundary between
the warm and cold air masses is called a front. Another example of lift is air
flowing up a mountainside.
WINTER STORMS ARE CONSIDERED
DECEPTIVE KILLERS ..... BECAUSE MOST DEATHS ARE
INDIRECTLY
RELATED TO THE STORM
· People die in traffic
accidents on icy roads.
· People die of heart
attacks while shoveling snow.
· People die of hypothermia
from prolonged exposure to cold.
Everyone is
potentially at risk during winter storms. The actual threat to you depends on
your specific situation. Recent observations indicate the following:
· Related to
ice and snow:
· About 70%
occur in automobiles.
· About 25%
are people caught out in the storm.
· Majority
are males over 40 years old.
· Related to
exposure to cold:
· 50% are
people over 60 years old.
· Over 75%
are males.
· About 20% occur in the home.
COLD
FROSTBITE
Frostbite is
damage to body tissue caused by that tissue being frozen. 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.
Warning signs - uncontrollable shivering, memory loss,
disorientation, incoherence, slurred speech, drowsiness, and apparent
exhaustion.
Detection - Take the person's temperature. If below 95F
(35C),immediately seek medical care! If medical care is not available, begin
warming the person slowly. Warm the body core first. If needed, use your own
body heat to help. Get the person into dry clothing, and wrap them 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 better. Do not warm
extremities (arms and legs) first! This drives the cold blood toward the heart
and can lead to heart failure.
The wind chill is
based on the rate of heat loss from exposed skin caused by combined effects of
wind and cold. 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.
AVOID OVEREXERTION, 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.
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When CAUGHT in a Winter Storm... |
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OUTSIDE |
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Find shelter: |
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· try
to stay dry |
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· cover
all exposed parts of the body. |
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No shelter: |
|
|
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· prepare
a lean-to, wind-break, or snow cave for protection from the wind. |
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· build
a fire for heat and to attract attention. |
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· place
rocks around the fire to absorb and reflect heat. |
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Do not eat snow: It
will lower your body temperature. Melt it first. |
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IN A
CAR OR TRUCK |
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Stay in your car or
truck. Disorientation occurs quickly in wind-driven snow and cold. |
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Run the motor about
ten minutes each hour for heat: |
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|
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· open
the window a little for fresh air to avoid carbon monoxide poisoning. |
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· make
sure the exhaust pipe is not blocked. |
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Make yourself visible
to rescuers: |
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|
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· turn
on the dome light at night when running engine. |
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· tie
a colored cloth (preferably red) to your antenna or door. |
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· raise
the hood indicating trouble after snow stops falling. |
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Exercise from time to
time by vigorously moving arms, legs, fingers, and toes to |
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keep blood
circulating and to keep warm. |
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|
|
AT
HOME OR IN A BUILDING |
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Stay inside. When
using ALTERNATIVE HEAT from a fireplace, wood stove, space |
|
heater, etc.: |
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· use
fire safeguards. |
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· properly
ventilate. |
No heat:
·
close off unneeded rooms.
· stuff
towels or rags in cracks under doors. · cover
windows at night.
Eat and drink.
Food provides the body with energy for producing its own heat. Keep the body
replenished with fluids to prevent dehydration.
Wear layers of loose-fitting,
lightweight, warm clothing. Remove layers to avoid overheating, perspiration,
and subsequent chill.
KEEP AHEAD OF THE STORM by listening to NOAA Weather Radio,
commercial radio, and television for the latest winter storm watches, warnings,
and advisories.
What to Listen For...
WINTER
STORM WATCH:
Severe winter conditions, such as
heavy snow and/or ice, are possible within the next day or two. Prepare now!
WINTER
STORM WARNING:
Severe winter conditions have begun or
are about to begin in your area. Stay indoors!
BLIZZARD
WARNING:
Snow and strong winds will combine to
produce a blinding snow (near zero visibility), deep drifts, and
life-threatening wind chill. Seek refuge immediately!
WINTER
WEATHER ADVISORY:
Winter weather conditions are expected
to cause significant inconveniences and may be hazardous. If caution is
exercised, these situations should not become life- threatening. The greatest
hazard is often to motorists.
FROST/FREEZE
WARNING:
Below freezing temperatures are
expected and may cause significant damage to plants, crops, or fruit trees. In
areas unaccustomed to freezing temperatures, people who have homes without heat
need to take added precautions.
BE PREPARED... Before the Storm Strikes
At home and at work...
Primary concerns
are the potential loss of heat, power, telephone service, and a shortage of
supplies if storm conditions continue for more than a day.
Have available:
· Flashlight
and extra batteries.
· Battery-powered
NOAA Weather Radio and portable radio to receive emergency information. These
may be your only links to the outside.
· Extra food and water.
High energy food, such as dried fruit or candy, and food requiring no cooking
or refrigeration is best.
· Extra medicine and
baby items.
· First-aid supplies.
· Heating
fuel. Fuel carriers may not reach you for days after a severe winter storm.
· Emergency
heating source, such as a fireplace, wood stove, space heater, etc.
· Learn to
use properly to prevent a fire.
· Have proper
ventilation.
· Fire extinguisher and
smoke detector.
· Test units
regularly to ensure they are working properly.
In cars and trucks...
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: · blankets/sleeping bags;
· flashlight with extra batteries;
· first-aid kit;
· knife;
· high-calorie, non-perishable food;
· extra clothing to keep dry;
· a
large empty can and plastic cover with tissues and paper towels for sanitary
purposes;
· a
smaller can and water-proof matches to melt snow for drinking water; · sack of sand (or cat litter);
· shovel;
· windshield
scraper and brush;
· tool
kit;
· tow
rope;
· booster
cables;
· water
container;
· compass
and road maps.
· Keep your gas tank
near full to avoid ice in the tank and fuel lines.
· Try not to travel
alone.
· Let someone know your
timetable and primary and alternate routes.
On the farm...
· Move animals to
sheltered areas. Shelter belts, properly laid out and oriented, are better
protection for cattle than confining shelters, such as sheds.
· Haul extra feed to
nearby feeding areas.
· Have a water supply
available. Most animal deaths in winter storms are from dehydration.
DRESS TO FIT THE
SEASON. Wear loose-fitting, light-weight, warm clothing in several layers.
Trapped air insulates. Layers can be removed to avoid perspiration and
subsequent 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.
Families should be prepared for all hazards that
affect their area and themselves. NOAA's National Weather Service, the Federal
Emergency Management Agency, and the American Red Cross urge each family to
develop 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
find each other? Will you know if your children are safe? Disasters may force
you to evacuate your neighborhood or confine you to your home. What would you
do if basic services - water, gas, electricity or telephones - were cut off?
Follow these basic steps to develop a family disaster plan...
I. Gather information about hazards.
Contact your local National Weather Service office, emergency management office
or civil defense office, and American Red Cross chapter. Find out what type of
disasters could occur and how you should respond. Learn your community's
warning signals and evacuation plans.
II. Meet with your family to create a
plan. Discuss the information you have gathered. Pick two places to meet: a
spot right outside your home for an emergency, such as fire, and a place away
from your neighborhood in case you can't return home. Choose an out-of-state
friend as your "family check-in contact" for everyone to call if the
family gets separated. Discuss what you would do if advised to evacuate.
III. Implement your plan.
1. Post emergency telephone numbers by phones;
2. Install safety features in your house, such as smoke
detectors and fire extinguishers,
3. Inspect your home for potential hazards (such as
items that can move, fall, break, or catch fire) and correct them;
4. Have your family learn basic safety measures, such as
CPR and first aid; how to use a fire extinguisher; and how and when to turn off
water, gas, and electricity in your home;
5. Teach children how and when to call 911 or your local
Emergency Medical Services number; (6) Keep enough supplies in your home to
meet your needs for at least three days. Assemble a disaster supplies kit with
items you may need in case of an evacuation. Store these supplies in sturdy,
easy-to-carry containers, such as backpacks or duffle bags. Keep important
family documents in a waterproof container. Keep a smaller disaster supplies
kit in the trunk of your car.
A DISASTER SUPPLIES KIT SHOULD
INCLUDE: A 3-day supply of water (one gallon per person per day) and food that
won't spoil one change of clothing and footwear per person one blanket or
sleeping bag per person a first-aid kit, including prescription medicines
emergency tools, including a battery-powered NOAA Weather Radio and a portable
radio, flashlight, and plenty of extra batteries an extra set of car keys and
cash special items for infant, elderly, or disabled family member.
IV. Practice and maintain your plan.
Ask questions to make sure your family remembers meeting places, phone numbers,
and safety rules. Conduct drills. Test your smoke detectors monthly and change
the batteries at least once a year. Test and recharge your fire extinguisher(s)
according to manufacturer's instructions. Replace stored water and food every
six months.
NOAA/PA 91002 ARC
4467
page prepared by:
Joan Von Ahn