WHAT IS A TORNADO?
A tornado is defined as a violently rotating column of air
extending from a thunderstorm to the ground. The most violent tornadoes are capable of
tremendous destruction with wind speeds of 250 mph or more. Damage paths can be in excess
of one mile wide and 50 miles long.
WHAT CAUSES TORNADOES?
Thunderstorms develop in warm, moist air in advance of
eastward-moving cold fronts. These thunderstorms often produce large hail, strong winds
and tornadoes. Tornadoes in the winter and early spring are associated with strong frontal
systems that form in Texas and Oklahoma and move eastward toward Caddo-Bossier area.
Occasionally, large outbreaks of tornadoes occur with this type of weather pattern.
Several states may be affected by numerous severe thunderstorms and tornadoes.
During the spring in the South-Central States, thunderstorms
frequently develop along a "dryline" which separates very warm, moist air to the
east from hot, dry air to the west. Tornado-producing thunderstorms may form as the
dryline moves east during the afternoon hours.
Along the front range of the Rocky Mountains, in the Texas
Panhandle, and in the southern High Plains, thunderstorms frequently form as air near the
ground flows "upslope" toward higher terrain. If other favorable conditions
exist, these thunderstorms can produce tornadoes.
Small tornadoes can even accompany tropical storms and hurricanes
that move over land. Tornadoes are most common to the right and ahead of the path of the
storm center as it comes onshore.
FREQUENCY OF TORNADOES
Tornadoes can occur at any time of the year.
Tornadoes are most likely to occur between 3 and 9 p.m. but have been
known to occur at all hours of the day or night.
The average tornado moves from southwest to northeast, but tornadoes
have been known to move in any direction. The average forward speed is 30 mph, but may
vary from nearly stationary to 70 mph.
WHAT TO LISTEN FOR
Tornadoes are possible in our area. Remain alert
for approaching storms.
Tornado Warning: A tornado has been sighted or indicated by weather radar. If a
tornado warning is issued for your area and the sky becomes threatening, move to your
pre-designated place of safety.
Severe Thunderstorm Watch: Severe thunderstorms are possible in our area.
Severe Thunderstorm Warning: Severe thunderstorms are occurring.
Remember, tornadoes occasionally develop in areas in which a severe thunderstorm watch or
warning is in effect. Remain alert to signs of an approaching tornado and seek shelter if
threatening conditions exist.
WHOS MOST AT RISK?
People in automobiles.
The elderly, very young and the physically or mentally impaired.
People in mobile homes.
People who may not understand the warning due to a language barrier.
Areas near rivers, lakes, and mountains are safe from
No place is safe from tornadoes. In the late
1980s, a tornado swept
through Yellowstone National Park leaving a path of destruction up
and down a 10,000-ft. mountain.
The low pressure with a tornado causes buildings to
"explode" as the tornado passes overhead.
Violent winds and debris slamming into buildings cause
most structural damage.
Windows should be opened before a tornado
approaches to equalize pressure and minimize damage.
Opening windows allows damaging wind to enter the
structure. Leave the windows alone; instead, immediately go to a safe place.
TORNADO SAFETY: WHAT YOU CAN DO
Before the Storm:
Develop a plan for yourself and your family for home, work, school
and when outdoors. Call OEP for assistance.
Have frequent drills.
Have a NOAA Weather Radio with a warning alarm tone and a battery
backup to receive warnings.
Listen to radio and television for information.
If planning a trip outdoors, listen to the latest forecasts and take
necessary action if threatening weather is possible.
If a warning is issued or if threatening weather approaches:
In a home or building, move to a pre-designated shelter, such as a
If an underground shelter is not available, move to an interior room
or hallway on the lowest floor and get under a sturdy piece of furniture.
Stay away from windows.
Do not try to outrun a tornado in your car; instead leave it
If caught outside or in a vehicle, lie flat in a nearby ditch or
Mobile homes, even if tied down, offer little protection from
tornadoes and should be abandoned.
Occasionally, tornadoes develop so rapidly that advance warning
is not possible. Remain alert for signs of an approaching tornado. Flying debris from
tornadoes causes most deaths and injuries.
Its up to you!
Each year, many people are killed or seriously injured by tornadoes
despite advance warning. Some did not hear the warning while others received the warning
but did not believe a tornado would actually affect them. The preparedness information in
this section combined with timely severe weather watches and warnings, could save your
life in the event a tornado threatens your area. After you have received the warning or
observed threatening skies, YOU must make the decision to seek shelter before the storm
arrives. It could be the most important decision you will ever make!
TORNADO SAFETY IN SCHOOLS
Every school should have a plan!
FAMILY DISASTER PLAN
Families should be prepared for all hazards that affect
their area. The Office of Emergency Preparedness urges each family to develop a family
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.
Gather information about hazards.
Contact the Shreveport National
Weather Service at 631-3669, the Louisiana OEP at 800-256-7036, or the American Red Cross
at 865-9545. find out what types of disasters could occur and how you should respond.
Learn your communitys warning system and evacuation plans.
Discuss the information you have
gathered. Pick two places to meet: a spot outside your home for an emergency, such as a
fire, and a place away from your neighborhood in case you cant 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.
Meet with family to create plan.
(1) Purchase a weather radio with automatic
warning: (2) Post emergency telephone numbers; (3) Install safety features in your house,
such as smoke detectors and fire extinguishers; (4) Inspect your home for potential
hazards (such as items that can move, fall, break or catch fire) and correct them; (5)
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; (6)
Teach children how and when to call 9-1-1; (7) 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 duffel bags. Keep important family documents in a waterproof
container. Keep a smaller disaster supplies kit in the trunk of your car.
Implement your plan.
A disaster supplies kit should include:
A 3-day supply of
water (one gallon per person per day) and food that wont spoil *one change of
clothing and footwear per person * a first aid kit including a battery-powered NOAA
Weather Radio and a portable radio, flashlight and plenty of extra batteries * an extra
set of car keys and a credit card or cash * special items for infant, elderly or disabled