Severe Weather
Shawnee Fire Department News

Severe Weather Terms
Tornado Awareness
Thunderstorm Awareness
Signs and Warnings
Preparedness
Family Disaster Plan
Response
Recovery
Six Common Lightning Myths
Informative Internet Sites




The Shawnee Fire Department would like to remind you of the hazards associated with severe weather. Knowing the safety precautions could prevent injuries and possibly save your life and/or someone else’s life. Know how to protect yourself and your family during severe weather and different emergency situations.


Severe Weather Terms
  • Tornado Watch indicates that conditions are right for a tornado to develop and that the sky should be watched.
  • Tornado Warning indicates a tornado has been sighted or spotted on radar. Warnings will give the location of the tornado and the area immediately affected by the warning.
  • Flood Watch means a flood is possible in your area.
  • Flood Warning means flooding is already occurring or will occur soon in your area.
  • Flash Flood Watch means flash flooding is possible in your area.
  • Flash Flood Warning means a flash flood is occurring or will occur very soon.
  • Thunderstorm Watch means conditions are favorable for severe weather to develop.
  • Thunderstorm Warning means areas where severe weather is imminent.

The “WATCH” and “WARNING” advisories are passed to local radio and television stations and broadcast over local NOAA Weather Radio stations serving the warned areas. These warnings are also relayed to local emergency management and public safety officials who can activate local warning systems to alert communities.


Tornado Awareness

Tornadoes are relatively short-lived local storms. They are composed of violently rotating columns of air that descend in the familiar funnel shape from thunderstorm cloud systems. The weather conditions that tend to generate tornadoes are unseasonably warm and humid earth surface air, cold air at middle atmospheric levels, and strong upper-level jet stream winds. Tornadoes can occur anywhere in the United States during any month of the year. However, the Great Plains and Gulf Coast States experience the largest number of tornadoes. The greatest frequency of tornadoes occurs in the months of April, May and June.

The destructive path of a tornado averages about 250 yards in width and 15 miles in length. In extreme conditions, a tornado may travel more than 300 miles and leave a path of total destruction more than a mile wide. Tornadoes will travel up to 60 mph, with wind speeds approaching 400 mph in the tornado’s center. Tornadoes usually travel from a westerly direction to an easterly direction.


Thunderstorm Awareness

By definition, a thunderstorm is a cloud that contains lightning and thunder. A typical storm is usually 15 miles in diameter lasting an average of 30 minutes. Every thunderstorm produces lightning, which kills more people each year than tornadoes.

Lightning often strikes outside of heavy rainfall and may occur as far as 10 miles from the rain. If you are outside during a lightning storm, seek inside shelter immediately and stay off the telephone. Debunking a myth, rubber-soled shoes and/or rubber tires provide NO protection from lightning. However, if lightning hits the car you are in, the steel frame of a hard topped vehicle will provide increased protection provided you are not touching metal when your car is hit by lightning.

A severe thunderstorm is a storm that contains large hail (three-quarters of an inch in diameter or larger), damaging or straight-line winds (58 mph or greater) and/or a tornado. A downburst is a strong out-rush of wind formed by rain-cooled air. Strong down-bursts, which produce extensive damage, are often mistaken for tornadoes. A down-burst can easily overturn a mobile home, tear roofs off houses and topple trees.

The National Weather Service considers a thunderstorm severe if it produces hail at least three-quarters of an inch in diameter, winds of at least 58 mph and/or a down-burst.

Heavy rain from thunderstorms can lead to flash flooding. The power of flowing water can easily sweep away trees, building, automobiles and people. Drivers needlessly die when they drive their cars into low water crossings and drown when the car is swept off the road.

On an average, it takes about two feet of water for a car to float downstream. However, it takes less than one foot of water for a smaller car to stall. Once a car stalls, the driver normally gets out to walk to safety. If the driver is not careful, he could be swept into deeper water beneath the low water crossing.

NEVER drive into a flooded area.
NEVER drive around road barricades.
NEVER assume the water isn’t deep. Looks can be deceiving. How many times have television crews captured dramatic footage of rescue workers plucking victims out of flooded water downstream caused by low water crossings? While the water may only look two feet deep, it might be closer to five or six feet deep.

Be proactive. If you are camping near a small stream, be prepared to move quickly if flooding occurs. Heavy rain upstream may lead to serious flooding near your campsite with little or no warning. Avoid camping near streams if rain is forecast.


Signs and Warnings

Tornadoes develop during severe thunderstorms. While not all thunderstorms create tornadoes, the potential is there. During violent weather, keep tuned to a local television or radio station for tornado reports.

If you are outside and see a funnel-shaped cloud with obvious rotating motion, it may be a tornado. As a tornado develops, it will produce a loud roar that grows louder as the funnel cloud touches the ground. When nearby, a tornado has a loud sound comparable to the combined roars of several jet engines.

The National Severe Storms Forecast Center in Kansas City issues Tornado Watches. Local National Weather Service offices issue Tornado Warnings. Local officials may sound sirens in a tornado warning.


Preparedness

The best preparation for a tornado is to designate a safe place in or around your home as a tornado shelter. Tornado shelters are safest if they are underground. A storm cellar or basement away from windows offers the best protection.

If neither of these is available, plan to find shelter under heavy furniture or mattresses near an inside wall of your house on the ground floor. Get under solid furniture or cover yourselves with mattresses pulled off the bed.
  • Plan tornado drills with your family so everyone knows what to do.
  • Know the location of the designated shelter where you work or go to school.
  • Plan to evacuate your manufactured (mobile) home.
  • Make an inventory of your household furnishings and other possessions.
  • Supplement the written inventory with photographs or video. Keep inventories and pictures in a safe deposit box or some other safe place away from the premises.


Family Disaster Plan

During a year, there are a lot of potential disasters that could impact your family:
  • A Hazardous Material accident could force your family to evacuate your home.
  • A winter storm, an earthquake or tornado could cut off basic services such as gas, water, electricity or phone service.

There are six basic types of supplies you should have packed in a special container (such as a large trash container, a backpack or a duffel bag) in case of a natural or man-made disaster.

Those supplies include:
  • Water – store one gallon per person per day.
  • Ready to eat food, canned juices, high energy foods, vitamins, comfort foods and of course special foods for infants or family members on a special diet.
  • First aid supplies including bandages, antiseptics, soap, latex gloves, and non-prescription drugs such as aspirin, antacid, anti-diarrhea medication, etc.
  • Clothing and bedding to include sturdy shoes, rain gear, blankets, hats, gloves, thermal underwear and sunglasses.
  • Tools and emergency supplies including:
    • battery operated radio
    • flashlights
    • fire extinguisher
    • pliers
    • shut off wrench
    • matches in a water proof container
    • liquid soap
    • personal items
    • household chlorine bleach
  • Special items for an infant, medication for family members, books and games for entertainment and important family documents.
  • Always keep your gas tank full!


Response

If you have a storm cellar or shelter, go to it immediately with your family. If no shelter is available, go to your basement and get under a heavy workbench or stairs. Do not position yourself directly underneath heavy appliances on the floor above you.

If your home has no basement, stay in the center of the house away from the windows or in a small room on the ground floor that is away from outside walls. Take cover under solid furniture or mattresses. Protect your head.

In mobile homes or vehicles, evacuate and take shelter in a substantial structure. If there is no nearby shelter, lie flat in the nearest ditch or ravine with your hands shielding your head.

In any large building, such as an office or department store, avoid all large, poorly supported roofs. Go to the basement or to an inner hallway on a lower floor.

Do not drive. You are safer in a home or basement shelter than in a car. If you are driving in a city and spot a tornado, get out of your car and go to a nearby building. If you are driving in open country, drive at a right angle away from the tornado’s path if you can safely do so. Do not try to outrun the storm. If you cannot avoid the tornado, get out of your car. Lie flat in the nearest depression, such as a ditch, culvert or ravine. Protect your head and stay low to the ground.

Lighting – What To Do
If you are caught outside in a thunderstorm, get inside a building or a car. If you must stay outside, keep away from metal, including golf carts, motorcycles, fences, metal lines or pipes. Stay below ground level, away from hilltops, open beaches or fields. And most importantly stay away from open water.

Lightning – Stay Inside
Each year lightning kills more Americans than tornadoes or hurricanes. Most of these deaths happen outside. If you are inside a building, or even a car, your chances of being struck by lightning are slim. Stay on top of weather conditions when planning camping trips, swimming, fishing, golf or other outdoor activities.

Never Drive Into Water
Never drive into a flooded area. It takes two feet of water on the road to make a car float. Once floating, the car will be swept downstream and will often overturn, trapping occupants inside. If your car stalls in high water, abandon it immediately – Move To Higher Ground.


Recovery
  • After a tornado passes, stay tuned to the local radio or TV station to get an all-clear signal before leaving your shelter. Sometimes more than one tornado will develop during a violent storm.
  • Re-enter buildings with extreme caution.
  • Be alert to fire hazards such as broken electric wires or damaged electrical equipment, gas or oil leaks, or smoldering piles of wet hay or feed. Report damaged utility lines to appropriate authorities.
  • Have damage to your property assessed by your insurance company.

Wind Damage on the Fujita Scale
  • F0 – Weak (40-72 mph) – chimneys are lightly damaged, branches break, signs blow down
  • F1 – Weak (73-112 mph) – Roofs are damaged, mobile homes overturned automobiles blow off road
  • F2 – Strong (113-157 mph) – Objects become airborne; crops flatten
  • F3 – Strong (158-206 mph) – Walls collapse, trains derail, cars are lifted and thrown, trees are uprooted
  • F4 – Violent (207-260 mph) – Well-constructed houses are leveled, large objects become airborne, crops are uprooted
  • F5 – Violent (261-318 mph) – Strong frame houses disintegrate, cars are thrown more than 100 yards, trees are debarked, and ground becomes barren

Six Common Lightning Myths
  1. Lightning never strikes twice. It strikes the Empire State Building in New York City between 22 to 25 times each year.
  2. Rubber tires or foam pad will insulate me from lightning. It takes about 10,000 volts to create a one-inch spark. Lightning has millions of volts and easily can jump 10-12 feet.
  3. Lightning rods will protect my house or outdoor festivities. Lightning rods are “preferential attachment points” for lightning. You do not want to “draw” lightning to any area with people nearby.
  4. Get off the water when boating, canoeing or sailing. Tall trees and rocky outcrops along the shore and on nearby land may be more dangerous places.
  5. A cave is a safe place in a thunderstorm. If it is a shallow cave or old mine with metal nearby, it can be a deadly location during lightning.
  6. Injured persons carry an electrical charge. Injured persons DO NOT carry an electrical charge and can be handled safely. Apply First Aid procedures to a lightning victim if you are qualified to do so. Call 911 or send for help immediately.

Informative Internet Sites
www.GoodStartsHere.org