Severe Weather Planning and Response: Tornadoes
You’ve seen the destructive force of tornadoes vividly illustrated on TV over the past month or so. Are you and your employees prepared to survive such a catastrophic event? Are your plans based on reality, or assumption? To plan effectively, it is important to separate fact from fiction so that your plan has credibility as well as effectiveness.
Many areas of the US have experienced severe tornadoes this spring, and the threat continues now that summer is almost here. The majority of tornadoes occur in the United States, Europe and South East Asia, but are also known to occur in many other places, such as Canada, South Africa, Australia, New Zealand, Japan, South America.
Since tornadoes can occur worldwide and pose a major threat to life and property, how to deal with these severe risks should be a part of every company’s emergency preparedness and response planning. Severe weather hazards should also be emphasized in your training program to provide employees with information about how to respond to such conditions both on and off the job.
Thanks to last week’s release of the new Superman movie, a new generation is being taught one of the worst ways to shelter from a tornado in the open- run for the nearest highway overpass. Here are a few myths that you may need to unlearn before writing, or updating, your workplace and personal tornado response plans:
“Opening the windows in your house before a tornado will reduce damage by balancing the pressure inside and outside the structure.
”False! Homes are damaged and destroyed by the extremely strong winds in a tornado, not pressure. If a tornado is approaching, you should seek shelter immediately. Taking the time to open all of your windows will put you in danger and will not protect your home from forceful winds.
“Tornadoes cannot cross lakes, large rivers or wide bodies of water.”
False! Tornadoes that form on land can cross bodies of water, including rivers and lakes. Tornadoes can also form on water. These tornadoes are called “waterspouts.” Never think that a body of water will protect you from a tornado.
“Tornadoes never strike the same area twice.”
False! Tornadoes can strike any area at any time, regardless of past history. For instance, Cordell, Kansas was hit by tornadoes on the same day, May 20, three years in a row. Also, three different tornadoes hit the same church in Guy, Arkansas on the same day.
“A tornado is more likely to hit a mobile home park.”
False! Tornadoes are not more likely to hit a mobile home park, but the chances of them doing more damage and destruction to mobile homes are greater than to other structures. There are thousands of mobile homes located in tornado alley, and the damage seen in mobile home parks is significantly worse than what would occur in a neighborhood of frame homes. Even the weakest of tornadoes can flip and destroy a mobile home, when a frame home would receive little to no damage in the same storm.
“Tornadoes can always be seen from far away.”
False! Not only do tornadoes not always have to appear as a visible funnel cloud, but they can also be hidden by heavy rainfall during the day or by darkness at night.
“If I am near a highway overpass, I should abandon my vehicle immediately and take shelter there.
”False! While a highway overpass is a sturdy structure that may offer protection from flying debris, it will not protect you from dangerous winds. In fact, an overpass can act as a wind tunnel and may cause accelerated wind that collect debris, causing you more harm. If you are in your vehicle and a tornado is approaching, you should pull your vehicle to the side of the road immediately, get out, and lay flat in a nearby ditch covering your neck and head.
“The safest place to take shelter from a tornado is in the southwest corner of a basement.”
False! While it was once widely believed that debris would not fall in the southwest corner of a structure that has now been rethought. The safest place to take shelter during a tornado is an interior room on the lowest floor of your home or building, as far as possible from exterior walls and windows. Even in a basement interior walls can provide additional protection from flying debris.
“If a tornado is not coming directly towards me, I am out of harm’s way.”
False! Tornadoes do not follow a specific path or route, and can change directions at any time. The only safe place to be during a tornado is in a location that offers shelter from high winds and debris.
“The damage to homes during a tornado is caused by an explosion from changes in air pressure.”
False! Homes are damaged by the strong winds produced by a tornado, not by the changes in the air pressure.
“Downward-bulging clouds mean that a tornado is forming.”
False! While downward-bulging clouds that show signs of a rotating motion can certainly mean a tornado is forming, not all downward-bulging clouds indicate a tornado. Some of these clouds are simply storm clouds and are completely harmless.
“Tornadoes do not hit big cities.”
False! Tornadoes can hit anywhere at any time. Several large cities have been hit by tornadoes throughout history, including Dallas, Miami, Minneapolis, Oklahoma City, Wichita Falls, Salt Lake City and St. Louis.
“A tornado cannot travel up and down hillsides.”
False! Tornadoes can travel up and down hillsides, and are just as violent and dangerous. Living on a hill will not protect you from a tornado.
“A tornado always forms and appears as a funnel cloud.”
False! A tornado can cause damage on the ground even when a visible funnel cloud has not formed. Also, if you see a funnel cloud that does not appear to be touching the ground, the wind and circulation may still reach the ground and cause extensive damage.
What to Watch For
Today, we’re fortunate to have advance warning of tornadoes, which allows us to save lives even though there’s usually little we can do to protect property.
Danger signals of a tornado include:
- Severe thunderstorms with frequent lightning, heavy rain, strong winds, and power failures
- Hail pelting down from very dark skies
- A roaring noise
- And of course, the trademark dark, spinning funnel shape from sky to ground
What to Do
The National Weather Service tracks weather systems with radar and can usually give advance warning of dangerous weather conditions. So when skies look threatening, check the local radio or television station for indications of severe storms or tornadoes.
If a tornado watch is in effect, this means you should prepare to take shelter and keep informed of the latest conditions. A tornado warning means that a tornado has been confirmed in the area, and people should take cover immediately.
When a watch is announced, any drapes in the work area should be closed to prevent flying glass and objects from injuring people if a tornado develops. An inspection of the area for other potential flying debris threats, such as patio chairs and tables, should be done at this time as well. The issuance of a warning is a signal to move to interior corridors and close the doors to windowed areas. Remain there unless asked to move to lower levels of the building or an all clear is announced.
It is crucial to understand the difference between a tornado watch and a warning. A Watch is your cue to prepare- to do the things necessary to minimize danger to persons and property. When a Warning is issued, its time to seek shelter, nothing more. No tidying up, no making last minute inspections, no calling the neighbors. When a warning is issued, there is no time for anything other than seeking secure shelter.
Away from work when a tornado approaches, people should abandon cars or mobile homes and find cover in a well-constructed building. If there are no suitable ones nearby, lie flat in the nearest ditch or culvert, and shield your head from flying debris with your hands.
In shopping centers or other large buildings, seek a designated shelter. The next best place to be–there or at home–would be a basement, or on the lowest floor, in the middle of the building behind an interior wall, well away from windows.
Please examine the additional information found at the following links!
- Five Things You Can Do To Prepare for Houston’s Spring Storms (local.allstate.com)
- How to prepare for a tornado: safety tips and resources (pennlive.com)
- Deadly Oklahoma tornado highlights need for safe rooms (smartsign.com)
- Identify Safe Locations in Your Apartment Building for Sitting Out Bad Weather (apartmentguide.com)
- Beyond the Green Screen: Severe Weather Sirens Clarified (wqad.com)
- OVERPASSES AND TORNADO SAFETY Not a Good Mix….. (noaa.gov)
- Tornado Facts and Safety Tips (ohio.gov)
- Tornado Safety Tips for School Administrators (ohio.gov) (pdf)