Tornado and Severe Weather Preparedness
Would you know what to do?
Alabama began 1998 quietly with only one tornado in the first three months. But then came April 8, 1998, when one of only two F5 tornadoes nationwide, the most powerful rating, struck parts of Jefferson and Tuscaloosa counties. "That tornado lasted just 45 minutes, and killed 32 people, making it the single deadliest tornado for 1998," according to Brian Peters who is Warning Coordination Meterologist with the National Weather Service's Birmingham office. "We (Alabama) ranked second to Florida in 1998 in the number of tornado deaths but we set a new record for the most tornadoes in a single year since 1950," said Peters.
There were 50 tornadoes in Alabama in 1998, eclipsing the old record of 45 for a single year. The tornadoes in 1998 were spread over five different months. April and September, a relatively low month for tornado occurrences, had the most tornadoes with 20 and 22, respectively. Six tornadoes were reported in May with one in February and one in June. All tornado deaths occurred on April 8th with 34 in two separate tornadoes. Injuries from tornadoes totaled 275.
"1998 lived up to its expectations of being a banner year for tornadoes in Alabama, said Peters. "However, we can expect a higher -than-usual occurrence of tornadoes in Alabama for the two years following an El Niño occurrence. So 1999 and 2000 could see significant storms," Peters noted.
Historically, Alabama's worst tornado disaster occurred March 21, 1932. Alabama suffered from two waves of tornadoes that balmy Monday afternoon. When it was over, more than 3000 people had been killed. In more recent history, the Demopolis-Brent-Wilsonville-Mt. Cheaha tornado of May 27, 1973, the Super Outbreak of April 3, 1974 (which almost totally destroyed downtown Guin, Alabama), the Huntsville tornado of November 15, 1989, and the Piedmont tornado of March 27, 1994, all tragically remind us of the power of tornadoes.
Tornadoes are violently rotating columns of air that descend from thunderstorms to come in contact with the ground. Tornadoes develop from thunderstorms when the wind variation with height supports rotation in the updraft. Severe thunderstorms and tornadoes occur most often in the spring months of March, April, and May. A secondary tornado season occurs in the Fall, typically in November. No month of the year is completely free from tornadoes.
Most tornadoes occur in the afternoon between noon and 6 pm. But tornadoes have occurred in every hour of the day and night, so no time of day is immune from tornado occurrences.
When these conditions come together, severe thunderstorms form and with them the potential for tornadoes.
Springtime tornadoes have wind speeds that vary from as little as 65 miles an hour to as high as nearly 300 miles an hour. Tornadoes move with thunderstorms that produce them at forward motions varying from nearly a standstill to over 70 miles an hour.
Planning - Key to Tornado Survival
Tornadoes develop very quickly; the violent ones, responsible for most deaths, tend to move very fast. In fact, forward speeds of over 60 mph have been observed! Once a tornado is underway, time for planning has passed and immediate action must be taken to protect ourselves. Our plan has to be ready to meet the test.
Preparedness plans come in all sizes as dictated by our individual and collective needs, but it always comes down to the indivdual. Betting that the storm will not strike you may be the most costly wager you ever make. Questions you should ask: Do you know the basic safety rules? How about your home shelter area; would your children know what to do if home alone? Are plans ready to move elderly or disable people to shelter quickly? Do you know the best source for obtaining warning information?
Lets think about these things and PLAN AHEAD. Basic severe weather preparedness plans must include:
Your local Emergency Management Agency, the National Weather Service, or your local Red Cross Chapter can help you with your planing. Brochures on severe weather safety are available upon request. Some safety films are also available from National Weather Service Offices and are loaned without charge to schools and other organizations. It is especially important that school officials understand the severe local storm warning procedures and the importance of tornado drills. School plans must include procedures for buses to follow because they are vulnerable to overturning and high winds.
The primary mission of the National Weather Service is to warn of impending hazardous weather. But even with today's knowledge and technology, we simply cannot warn of every storm when we are dealing with something as volatile as tornado development or flash floods. Storm spotters, radar, and satellite reports all help, but tornadoes can and do develop without being detected. Advance warning time is often only a few minutes and may be only a few seconds. Preparedness is the other key in dealing with this threat.
The National Weather Service and your Emergency Management Agency urge you and your family to take time now to review tornado safety rules.
Knowing what to do means understanding terms used in the warning process.
TORNADO WATCH is issued by the National Weather Service when atmosphereic conditions are favorable for tornado development. Listen to NOAA Weather Radio or commercial radio and television stations for the latest weather information. Stay informed! Review safety precautions wherever you are. Keep an eye out for threatening or rapidly changing weather conditions and be prepared to go to a safe place.
A TORNADO WATCH is normally issued for a large area covering a whole state or a large part of several states. The WATCH is intended to give you time to prepare, time to review safety rules. The sky may be blue, but weather changes could be just over the horizon. Begin preparing when you hear the watch.
TORNADO WARNING is broadcast when a tornado has been detected by radar or a tornado has been reported. A TORNADO WARNING is usually issued for one or two counties. If the tornado warning is for your county, you should seek a safe shelter immediately.
Before a watch or warning is issued, National Weather Service meterologists may issue special outlooks and/or place wording within forecasts to alert you to possible severe weather ahead. The intent is to keep people informed and aware.
Remember, tornadoes form quickly! You may have only a few seconds to react and find shelter. When a tornado threatens, your immediate action can save your life! Seconds do save lives! Know what to do.
Safety Rules
In general, get as low as you can. A basement below ground level or at least the lowest floor of a building offers the greatest safety. And, put as many walls between yourself and the outside as possible. Avoid windows at all cost!
Homes or small buildings: go to the basement or to a small interior room such as a closet or bathroom or an interior hall on the lowest level. If available, get under something sturdy like a heavy table. Protect yourself from flying debris with pillows, heavy coats, blankets, or quilts.
Schools, nursing homes, hospitals, factories, and shopping centers: go to a pre-designated shelter area. Basements are the best, but interior hallways on the lowest floor usually offer protection. Close all doors to the hallway for greater protection.
Mobile homes or vehicles: leave them and go to a strong building. If there is no shelter nearby, get into the nearest ditch and lie flat with your hands shielding your head.
Stay away from windows! Don't bother opening or closing them. It won't protect the structure anyway. You'll just waste time and put yourself, and possibly others, at greater risk. Use those valuable seconds to find a place of safety.
Stay away from doors, windows, and outside walls. Protect your head!
Safety does not stop after the storm has passed. Everyone should be aware of the many dangers that might exist after bad weather has moved out of the area.
Thunderstorm wind reached damaging force in Alabama at least 267 times during 1998 and caused millions of dollars worth of damage. There were three deaths in 1998 along with 18 injuries caused by thunderstorm wind. Damaging thunderstorm wind events remain much more common than tornadoes in Alabama. In a typical year, Alabama is likely to experience 10 to 20 times as many wind events as tornado events. Not only can severe thunderstorms produce injury and damage from violent straight-line hail, but tornadoes can and sometimes do develop very quickly from these storms. Severe thunderstorms will continue to take their toll on lives and property but we can lessen their impact by taking severe thunderstorm warnings seriously.
A severe thunderstorm is defined as having wind of at least 58 mph and/or hail ¾ of an inch in diameter or larger. Severe thunderstorm winds can gust to more than 100 mph, overturning trailers, unroofing homes, and topling trees and power lines. While dime size hail denotes a severe thunderstorm, hail as large as grapefruit has occurred. The danger to serious injury from hail is not hard to imagine when you consider that a good-sized hailstone may fall at speeds near 110 mph.
Severe thunderstorms can strike any time of the year, but, like tornadoes, are much more frequent in the spring months of March, April, and May. Alabama also has a "secondary" severe weather season in November and early December. Severe storms that develop on a summer day are usually more isolated. However, some of the most dangerous and intense lightning may occur with summer storms. This is a fact well worth our attention since summer is the time of the year when outdoor activies are at a maximum.
The best defense against thunderstorms is to stay inside a substantial building. Thunderstorms do not usually last for a long time and will generally pass in less than an hour. When thunderstorms are expected, be sure to pick up loose objects around your home or business. Small items can become deadly in strong wind, and flying debris can cause serious damage to other property.
Lightning - The Underrated Killer
Lightning was responsible for only one death and three injuries in Alabama in 1998, about the same as the previous year. Since 1990, lightning has killed 14 people and injured 175 in the state. Lightning has been rightfully called "the underrated killer" since it does not usually get headline attention. Nationally, the average toll is around 80 deaths and 500 injuries. In an average year, lightning will claim more victims than tornadoes or hurricanes.
Every thunderstorm contains this potential killer. Whether it is the large spring-time severe storm or a more common afternoon variety, that electrical charge, which may reach 100 million volts, is always present and searching for the path of least resistance to complete the circuit. It might strike you, an isolated tree, or an object out in the open. Keep in mind that you do not have to be standing directly beneath a cloud to be hit.
Take some time now to learn or refresh your memory on lightning safety rules. That quick dash out in the open when a thunderstorm is in the area may unnecessarily expose you to the possiblity of being struck. Is it worth the risk?
There were seven flood related deaths in Alabama during 1998 that occurred in 98 documented flash flood events. During the past eight years, 32 people have lost their lives in flash flooding. On average, flooding and flash flooding account for about as many deaths nationally each year as lightning, tornadoes, and hurricanes combined! We must ensure that our preparedness plans include every possile step that can be taken to prevent the tragic loss of life that can occur during floods.
Advanced planning is important, but obvious dangers should not be under estimated. These include such activities as allowing children to play near a swollen drainage ditch or small stream, or attempting to drive or walk across flooded roadways or bridges. Such acts take a needless toll because the powerful force of moving water is easily underestimated.
Floods, similar to tornadoes and severe thunderstorms, are generally most frequent and intense during the late winter and spring, but can develop at any time of the year when conditions are right. The flooding that occurred during March and April of 1979 claimed 15 lives in Alabama. Also, the flooding of February and March of 1990 claimed 16 lives.
While flooding can be divided into two general categories, flash floods and mainstream flooding along rivers and streams, both hold the potential for causing death, injury, and the destruction of property. Our safety plan must include ways to deal with each type.
River flooding along major streams is generally slower to develop than flash flooding. There are exceptions to this, especially near headwater areas of smaller rivers where the time lag between the runoff from heavy rain and the onset of flooding can be very short. On the other hand, it make take several days or maybe a week for a flood crest to pass downstream points on major rivers.
The National Weather Service issues River Flood Warnings when rivers are expected to rise above flood stage. Crest forecasts for specific points downstream are given along with known flood stages for each point. It is important that everyone living near a river know how to react to the various flood crest forecasts that may be issued. While there is more warning lead time in most cases than with flash floods, advanced planning and preparation is essential to safeguard life and property from the dangers of mainstream flooding.
Flash flooding can occur almost anywhere in Alabama. Flash flooding can but does not necessarily occur in the classic "wall--of-water" concept. Simply stated, it is too much water in too short a time. Whether it occurs from excessive rainfall or possibly a dam failure, flooding develops very quickly. Rapidly rising water in a low area or near a drainage ditch or small stream may not be as spectacular as a rushing wall of water down a canyon, but it can be just as deadly. And with our changeable weather, we have gone from drought conditions to flash flooding within a few hours.
The National Weather Service issues a Flash Flood Watch when conditions are detected that could result in flash flooding within the desgnated watch area. A Flash Flood Warning is issued when flash flooding has been reported or is imminent. Preparedness plans must include being familiar with these items as well as all flood safety rules.
Also, you should be familiar with the land features where you live, work, or frequently visit. Is it in a low area, near a drainage ditch, or small stream, or below a dam?
Flash flooding sometimes develops with no advance warning. During periods of heavy rain, it is best to think flash flooding and be ready to respond quickly if flooding is observed or a warning is issued. Planning now with proper response should one of these events occur in your area can save your life. Remember that floods come in varying degrees of intensity. Although the ones you may have experienced in the past may have caused little concern, that major event could still be ahead,.
Flash Flood Safety Rules