Tornadoes are the most violent storms in nature’s arsenal. Winds can reach more than 300 mph and the storms are often accompanied by damaging hail and lightning. A tornado is defined as a violently rotating column of air extending from the base of a thunderstorm to the ground. Air moves rapidly upward around a tornado center. This distinguishes tornadoes from microbursts, which often do tornado-like damage and can be mistaken for tornadoes. In contrast to the upward rush of air in a tornado, air blasts rapidly downward from thunderstorms to create microbursts.
A tornado watch means conditions are favorable for the development of tornadoes. Remain alert to further weather updates while under a tornado watch.
A tornado warning means either the National Weather Service sees tornadic activity on its doppler radar or a storm spotter reports seeing a tornado. When a tornado warning is issued, Emergency Management will sound San Angelo's warning sirens. Take cover immediately and remain alert to further weather alerts.
An approaching cloud of debris can mark the location of a tornado even if a funnel is not visible. Before a tornado hits, the wind may die down and the air may become very still. Tornadoes generally occur near the trailing edge of a thunderstorm. It is not unusual to see clear skies behind a tornado.
Tornado strength is measured by the "Fujita Scale," which categorizes tornado severity (F0 being the least severe and F5 the most) based on damage observed, not recorded wind speeds. Wind speeds referred to in this scale are estimates intended to represent the observed damage.
When a tornado is coming, you have only a short time to make life-or-death decisions. Advance planning and quick response are keys to surviving a tornado.
Before a tornado
1. Write a disaster plan.
2. Build your disaster kit.
3. Conduct tornado drills each tornado season. 4. Designate an area in the home as a shelter, and practice having everyone in the family go there in response to a tornado threat. 5. Discuss with family members the difference between a "tornado watch" and a "tornado warning."
During a tornado
If at home
1. If you have a tornado safe room or engineered shelter, go there immediately.
2. Go at once to a windowless, interior room, storm cellar, basement or lowest level of the building.
3. If there is no basement, go to an inner hallway or a smaller inner room without windows, such as a bathroom or closet.
4. Get away from the windows.
5. Get under a piece of sturdy furniture such as a workbench or heavy table or desk and hold on to it.
6. Use arms to protect head and neck.
7. If in a mobile home, get out and find shelter in a building with a strong foundation. Mobile homes are particularly vulnerable because they can overturn easily. If shelter is not available, lie in a ditch or low-lying area a safe distance away from the unit.
If at work or school
1. Go to the area designated in your tornado plan.
2. Avoid places with wide-span roofs such as auditoriums, cafeterias, large hallways or shopping malls.
3. Get under a piece of sturdy furniture such as a workbench or heavy table or desk and hold on to it.
4. Use arms to protect head and neck.
1. If possible, get inside a building.
2. If shelter is not available or there is no time to get indoors, lie in a ditch or low-lying area or crouch near a strong building. Be aware of the potential for flooding.
3. Use arms to protect head and neck.
If in a car
1. Never try to out-drive a tornado in a car or truck.
2. Get out of the car immediately and take shelter in a nearby building.
3. If there is no time to get indoors, get out of the car and lie in a ditch or low-lying area away from the vehicle. Be aware of the potential for flooding.
After a tornado
1. Help injured or trapped persons.
2. Give first aid when appropriate.
3. Don't try to move the seriously injured unless they are in immediate danger of further injury.
4. Call for help.
5. If you smell gas, do not turn on any appliances or switches. This includes using phones, flashlights or a cell phone.
6. Turn on radio or television to get the latest emergency information.
7. Stay out of damaged buildings. Return home only when authorities say it is safe.
8. Use the telephone only for emergency calls.
9. Clean up spilled medicines, bleaches or gasoline and other flammable liquids immediately. Leave the building if you smell gas or chemical fumes.
10. Take pictures of the damage - both to the house and its contents - for insurance purposes.
Myth: If traveling when a tornado hits, an underpass is a safe place to ride it out.
Fact: Most of us have seen the famous video of the people caught by a tornado who sought shelter under an overpass. In reality, they were lucky. Wind speeds are increased as they are "squeezed" through an underpass. It is safer to get out of the car and lie in a ditch away from the vehicle.
Myth: Opening the doors and windows will prevent your house from "exploding" in a tornado.
Fact: This myth is based on the idea that the sudden pressure change associated with twisters will cause the house to explode. However, houses are not air-tight and the pressure change is not so rapid that your house will explode if you keep your windows and doors shut. Opening the doors and windows will just remove a barrier between you and flying debris.
Myth: The southwest corner of the house is the safest location during a tornado.
Fact: Always go to the lowest level and center of the house, preferably a small interior room such as a bathroom during a warning.
Myth: Cities, hills and rivers have natural protection from tornadoes.
Fact: Tornadoes have no barriers. They can and will cross hills, mountains, rivers, etc. Several major cities in the U.S. have been victims of tornadoes, including Dallas and Fort Worth.
Myth: Mobile homes attract tornadoes.
Fact: Mobile homes are no more likely to be struck by a tornado than other buildings. However, they are more vulnerable to wind damage when a tornado or other high-wind event occurs.