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Are You Ready For Tornado Season?
After an often brutal winter at times—and despite the often fickle nature of the weather in recent weeks—astronomical spring is finally here. And while winter can bring extreme weather hazards such as blizzards and ice storms, spring can bring its own brand of extreme weather. In addition floods, lightning, and severe thunderstorms, springtime is the peak season of year for tornadoes.
Tornadoes—those violent, dangerous, and typically destructive and rapidly-rotating columns of air—strike somewhere in the U.S. every year. Sometimes, they strike in sparsely-populated open fields and country sides. But when they strike in or around populated areas, the result is usually damaged or destroyed homes and property, injuries, and—in worse-case scenarios—deaths. Tornadoes can (and have) strike in every state in the union, and in every month of the year (see: “The Dangers of Wintertime Tornadoes”).
What Makes Tornadoes So Dangerous
The damage, injuries, and deaths (often) resulting from tornadoes come from the incredibly power winds they can generate. In the most powerful and violent tornadoes (those rated EF-4 and EF-5), wind speeds can range between 200 and 300 mph (321-482 kph)...or higher! Wind speeds of that magnitude can cause automobiles to become airborne, rip homes down to their foundations, and turn broken glass, wooden shards, and other debris into lethal missiles that can easily pierce human flesh. In fact, flying debris thrown through the air at high velocities account for the greatest number of injuries and fatalities in tornadoes. And in the strongest tornadoes, the winds have been known rip sections of grass and dirt from the earth, as well as strip asphalt pavement from the ground.
Aside from the powerful winds they generate, tornadoes are dangerous for another reason; their unpredictability. Though tornadoes generally travel in a path from the southwest to the northeast, this is not always the case. Their often erratic nature can force them to travel in any direction, change direction in mid-path, or even remain stationary over a specific area for an indeterminate period of time. The forward speed of a tornado range from being almost stationary to more than 60 mph (95 kph). However, a typical tornado travels at around 10–20 miles per hour (16 - 32 kilometers per hour).
And while tornadoes can (potentially) occur in all parts of the country, at all times of the year, there places and times where and when tornadoes are likely to occur more frequently.
While tornadoes can strike just about anywhere in the world where the proper weather conditions exist, they are most likely to strike within the region of the U.S. known as “Tornado Alley.” Tornado Alley is a term coined by meteorologists and weather researchers that is applied to a wide section of geography located in the central part of the U.S. that experiences a high frequency of tornadoes. This region of particularly active tornado activity extends the length of the continental U.S. from northern Texas to North Dakota, and stretches wide from the eastern borders of Texas, Oklahoma, Kansas, and the Dakotas east to areas of Iowa and Missouri. What makes this particular region is ideal for tornado formation is its perfectly situation position at the intersection of dry polar air from Canada, and warm moist tropical air from the Gulf of Mexico. This makes Tornado Alley an ideal territory for the frequent formation of the atmospheric instability needed to spawn tornadoes.
In fact, because of the abundance of the right weather conditions, tornadoes that occur within Tornado Alley tend to be particularly strong. Back in 2003, the small town of Manchester, South Dakota was totally destroyed by a powerful mile (1.6km)-wide tornado. So complete was the destruction left by the level EF4 (the second most powerful type of tornado on the EF0-EF5 Enhance Fujita Scale) tornado that the town of 109 was never rebuilt; in its place now stands a monument to where the town of once stood. And more recently in 2011, the catastrophic EF5 tornado that struck the city of Joplin, Missouri destroyed nearly 25% of the city’s homes and businesses and took the lives of some 155 of the city’s residents. While some 1,000 tornadoes strike someplace in the U.S. each year, most strike in Tornado Alley. For this reason, residents in the middle section of the country should be the most vigilant when it comes to keeping an eye on the weather.
As mentioned before, favorable conditions for tornadoes in the United States can occur at any time of the year. However, tornadoes are most likely to occur--for the majority of the country--beginning in early spring (March) through the early to mid-summer (mid-June); this includes the areas encompassing "Tornado Alley." This is the time of year meteorologists weather forecasters refer to as being "tornado season," the period of the year that the greatest number of tornadoes occur in the U.S. In areas of the Southern U.S., tornado season runs from late fall (November) through early spring (march). This is because of shifting weather patterns that move tornado-producing instability from the middle of the country to the southern half of the country. Also, the strong thunderstorms capable of producing tornadoes usually form when the temperature is at its highest; during the warmest time of the day, when daytime heating fuels their formation. Typically, the time between 3:00 p.m. to 7:00 p.m. represents the peak period of the day for tornadoes to occur. But they have been known to occur at any time of the day...or night. In fact, nighttime tornadoes are more frequent in the Southern portion of the U.S., due to the longer periods of high temperatures.
Because of this ever-present threat of tornadoes (as well as other types of severe weather),the National Oceanic and Atmospheric Administration (NOAA) in conjunction with the Federal Emergency Management Agency (FEMA) initiated National Severe Weather Preparedness Week back in 2012. Designated the first week of March, National Severe Weather Preparedness Week is a recognition meant to prompt state and local governments, as well as private organizations and citizens to both develop and put into practice proactive plans in the event should severe weather events such as tornadoes occur. In spite of the government efforts to encourage tornado and severe weather preparation, there is no actual “designated” time to make plans for tornado safety; anytime during the early spring is idea for planning ahead in anticipation of the tornado threat. And for anyone considering creating a tornado emergency plan, the key to crafting an effective plan is being able to anticipate both needs and concerns as they relate to surviving this particular severe weather threat. Concerns to consider include:
Being Aware of Threatening Weather
As the transition from cold to warmer seasons takes hold across the Northern Hemisphere, weather patterns can often become volatile. Clashing masses of warmer humid air and colder drier air will occasionally combine to form active weather fronts. It is at these points in the atmosphere where severe weather--in the form of severe thunderstorms and tornadoes--often occurs. Sometimes, weather forecasters can anticipate the potential for the outbreak of severe weather along these fronts days before the conditions actually form. When the potential for the “high risk of severe weather” is communicated by NOAA and its sister agencies (e.g., The National Storms Prediction Center and the National Weather Service), this is the time to become watchful for threatening weather.
As the probability for the likelihood of severe weather—including tornadoes—increases, the National Weather Service will issue either a “tornado watch” or “tornado warning.” As weather changing conditions warrant, these short-term weather advisories (or alerts) will be broadcast repeatedly over special weather radios (which can be purchased at most major retailers), over commercial radio and television stations, and over news and weather-themed websites. This means that tornado watches will be issued whenever weather conditions (general atmospheric instability) creates the potential for tornado-spawning storms, while tornado warnings will be issued whenever a tornado is indicated by either trained spotters or by radar. Additionally, many news and weather media outlets offer free web-based smart phone and tablet apps (such as the American Red Cross-sponsored Tornado app) that can keep users apprised of tornado alerts, as well as other threatening weather conditions.
Its also a good idea to, in the months leading up to the start of the tornado season, to purchase and stock up on anticipated needs. Create an "emergency tornado kit" that includes extra amounts of food and water first and foremost (a minimum of a 3-day supply). Dry foods, prepackaged foods, and/or foods that require little or no preparation (i.e., cooking) are the best options. This is because power might be disrupted in the aftermath of a tornado, and attempting to prepare foods that normally require cooking may not be possible. The emergency kit should also contain a basic emergency medical kit and/or first-aid supplies. Items such as bandages, disinfectants, over-the-counter pain-relievers, ointments, and such may be needed in case of minor injuries…since drugstores emergency personnel might be otherwise preoccupied with those who might be injured, and may not be able to arrive if needed. Also, consider storing flashlights (or glow sticks), batteries, candles, matches, a basic tool kit, a hand-crank radio/television, and extra cell phone batteries with the emergency kit. Most--if not all--of these items might be needed in worse-case situations that involve a much property damage, disruptions to utilities, and/or delays in first-responders attempting to reach those in need of assistance.
Finally, in the improbable likelihood that someone might find themselves in the absence of technology, a low-tech observation of weather conditions might actually make the difference between being safe and a possible life-and-death scenario. During threatening weather, particularly if a tornado watch or warning is issued, it’s advisable to watch the sky for signs that a tornado might be forming. These signs include: storms that produce large and/or intensive hail; dark clouds—especially those appearing to have a greenish hue; heavy rain; a large hanging cloud base from storm clouds, especially if the hanging cloud base begins to rotate; swirling patterns of debris on the ground under low-hanging clouds; a loud roaring noise (especially if the wind begins to picks up noticeably and/or suddenly); and/or the appearance of a funnel-shaped column of condensation and air dropping from the clouds. On a few occasions, many people have noticed just right just before a tornado, the air becomes eerily still, and unusually quiet. In many cases (but not always), local municipalities will activate tornado sirens to warn those outdoors of the danger. When these or a combination of these circumstances are observed, its highly advisable to seek shelter right away.
Considering that the powerful winds of a tornado winds can theoretically exceed the record 318 mph (511 km/h) winds produced by the 1999 Moore, Oklahoma tornado, no structure or building can provide absolute safety during these storms. However, being indoors is far preferable to being outdoors. And there are places in most buildings that provide enough shelter during a tornado to increase the likelihood of survival, and decrease the incidence of injury; know where these places are! In the home, the basement or an underground storm shelter provides the best place to take cover. Additionally, taking cover under a sturdy table or other heavy furniture (such as a billiard table or work bench) can add protection from falling debris.
But some areas of the country—namely those in the South and Southeastern U.S., where the ground consists of heavy amounts of dense rock and/or where the local water tables are high—basements are rare. For those living in these regions, the goal in a tornado-related emergency is to place as many walls between one’s self and the outside of the home or dwelling. To do that, the best place to take shelter is in an interior room such as a closet or a bathroom (in fact, interior bathrooms make a preferable alternative in such an instance because the plumbing in the walls surrounding the bathroom can form a frame of added protection, anchoring the room so to speak). In the most tornado-prone regions of the country, many property owners have contracted construction companies to build tornado “safe rooms.” These hardened windproof bunkers provide an area within or underneath the home that occupants can take shelter in during a tornado warning.
Many places of public accommodation such as schools and government buildings have designated rooms which double as shelters in the event of a tornado. What’s more, many public schools and workplaces have practiced contingency plans to help facilitate evacuation to designated shelters in case of need. In most cases, these rooms will be located in the innermost portions of the building. Furthermore, some areas of the country have public storm shelters. These are usually sturdy buildings (such as fire stations, and municipal government office buildings) owned and operated by local governments, and which are are designated to hold a small number of homeowners without storm shelters of their own. In most cases, these public shelters only open their doors to the public during tornado watches, so it is best to know where the public storms shelters are beforehand.
In taller buildings, inner stairways and/or restrooms tend to be designated shelters. Knowing beforehand where these locations are within buildings can be vital to survival if they are needed. But there are instances when planning is not always possible, such as when one find themselves in a store or other business during a possible tornado. In such cases, it may become necessary to improvise. If this scenario becomes a reality, quickly observe the surroundings and take note of any enclosed spaces, especially those designed to provide security or storage; such rooms tend to be constructed with an additional amount of sturdiness. In a store, this may be cooler for liquids; in a bank, it may be the money vault. The idea is to relocate to someplace within such a building that might increase the likelihood of survival from the primary killer in tornadoes—impact from everyday objects turned into high-velocity projectiles from a tornado’s winds.
What Not To Do
Finally, when it comes to tornado safety, knowing what not to do is just as important as knowing what to do. If at home, do not waste time opening windows to “equalize the pressure and limit damage.” That particular myth was debunked long ago as being ineffective at preventing destruction to a building. Also, resist the urge to head outdoors to videotape an oncoming tornado. The speed on an oncoming tornado can be easily be misjudged by someone observing it. This might very well result in miscalculating the danger of an approaching tornado...until it is too late.
If driving, do not try to outrun a tornado. Although it is possible, tornadoes can (and do) often make sudden changes in speed, strength, and path of travel—all of which are unpredictable to someone attempting to escape by driving. DON'T take cover under a bridge or overpass. Contrary to common belief, overpasses don't provide shelter from tornadoes. In fact, the reality is that in a tornado winds can actually accelerate under such structures, and the structures themselves can come apart and create deadly debris.
And do not remain in the automobile. The best course is to get out and either get out and seek shelter in a nearby building, or find an indentation in the ground of some sort and get into it, such as a ditch. Lay as flat as possible. The head should be covered the head to protect it from flying debris.
If outdoors during an approaching tornado, DO NOT seek shelter around trees, vehicles, or other objects that can potentially lifted off the ground by strong winds (as they can become airborne missiles). Either seek safety in a sturdy shelter or (if this isn't available), lie down in the deepest gully, ditch, or depression in the ground that can be found, and cover the head. There is likely to be airborne objects flying around, so it will become imperative to keep as flat as possible to the ground.
While tornado season is active primarily in the early spring and early summer months (i.e., “tornado season”), tornadoes can occur during any time of the year when the proper weather patterns exist. What’s more, they can occur in any state in the U.S., but tend to occur more throughout “tornado alley” during this period. Being aware of day-to-day weather forecasts and being proactive in planning ahead—primarily during tornado season—are the best ways to stay safe from the threat of tornadoes.
- The No-Nonsense Guide To Tornado Safety (Enhanced Edition) by Jeffery Sims, Paperback | Barnes &
This book can save your life! The No-Nonsense Guide To Tornado Safety (Enhanced Edition) contains all the information needed to prepare for tornado season, as well as the "do's" and "don't's," and several pages of listing for public tornado shelters
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