Tornadoes are vertical funnels of quickly spinning air. Their winds may surpass 250 miles an hour and clear a pathway a mile broad and 50 miles long.
Also known as twisters, tornadoes are born in thunderstorms and are often followed by hail. Huge, persistent thunderstorms called supercells spawn the most destructive tornadoes.
These violent storms occur worldwide, but the United States is a major hotspot with about a thousand tornadoes every year.
The single most violent tornado to ever hit the United States was the “Tri-State Tornado.” It killed 695 people and injured 2,027 people in 1925. The tornado went on for 219 miles, making it the longest ever recorded.
What is a tornado?
A tornado is a vigorously rotating column of air that extends from a thunderstorm to the ground. A dark, greenish sky often portends it, black storm clouds gather, and a baseball-size storm may fall.
A funnel abruptly rises, as though falling from a cloud. The funnel hits the ground and roars ahead with a sound like that of a cargo train approaching. The tornado damages everything in its path.
Because wind is transparent, it is difficult to recognize a tornado unless it forms a condensation funnel caused by water droplets, dust, and waste. Tornadoes can be among the most destructive happenings of all atmospheric storms to experience.
How does a tornado form?
The most extreme tornadoes come from supercells, large thunderstorms that have winds already in rotation. About one in a thousand storms becomes a supercell, and one in five or six supercells produces a tornado.
Tornadoes can happen at any time of the year, but they are more common during a distinct season in early spring for the states along the Gulf of Mexico. The season follows the jet stream — as it swings farther north and so does tornado activity. There are commonly more tornadoes in May than any other month, but April’s twisters are sometimes more intense.
Although they can occur at any time of the day or night, most tornadoes form in the late afternoon. By this time, the sun has heated the ground and the atmosphere enough to generate thunderstorms.
Tornadoes form when warm, humid air clashes with cold, dry air.
The denser cold air is exerted over the warm air, usually generating storms. The warm air rises through the colder air, producing an updraft. The updraft will start to rotate if winds differ distinctly in speed or direction.
As the rotating updraft, called a mesocycle, brings in more warm air from the moving thunderstorm, its rotation speed increases. Cool air fed by the jet stream, a strong wind band in the atmosphere, provides even more energy.
Water droplets from the mesocyclone’s moist air form a funnel cloud. The funnel proceeds to grow, and eventually, it descends from the cloud. When it touches the ground, it becomes a tornado.
How to predict a tornado?
The first step in predicting the possible occurrence of tornadoes involves identifying regions where conditions are favorable to the growth of powerful thunderstorms.
Primary components for the appearance of such storms are cool, dry air at middle levels in the troposphere superimposed over a layer of moist, possibly unstable air near the surface.
Forecasters in the United States have learned to monitor the wind profile in regions of instability carefully and to measure how temperatures and winds will develop within a day, while at the same time tracking the movement and power of the jet stream.
Meteorologists use Doppler radar, satellites, weather balloons, and computer modeling to watch severe storms and tornadic activity skies.
Doppler radars record wind speeds and recognize areas of rotation within thunderstorms. Since Doppler radar has been in use, the warning time for tornadoes has grown from less than five minutes in the 1980s to an average of 13 minutes by the late 2000s.
When weather conditions are favorable for tornado formation, the National Weather Service issues a tornado watch. When a tornado has been sighted or indicated on radar, a tornado warning is declared.
How to survive a tornado?
Understanding what to do when you see a tornado or when you hear a tornado warning can help protect you and your family. People face hazards from too high winds and risk being struck by flying and falling objects during a tornado.
After a tornado, the ruins left behind professes additional damage risks. Although nothing can be done to prevent tornadoes, there are steps you can take for your health and protection.
Tornado survival tips
- Have a family tornado plan and know where you can securely take refuge.
- Closely monitor NOAA Weather Radio.
- Install a tornado safe room or storm shelter constructed to FEMA 320 standard. Always use a permitted contractor to install a safe room within, adjacent to, or outside your home.
- Take refuge in a certified and approved storm shelter, safe room, or a community shelter identified as an official tornado shelter. Community shelters may include stores, malls, churches, even airports.
- If no shelter is available:
- Indoors – Go to the lowest floor, a small, central room, below a stairwell, or an interior hallway with no windows. Duck down as low as possible to the floor, face down, and cover your head with your arms. Cover yourself with a mattress, blanket, helmet, or other compact covering.
- Mobile home – Move out. Even if your home is tied down, it is not as safe as a strong building. Go to the nearest stable structure. Do not seek refuge under a walkway, bridge, or in a drainage canal. If you cannot safely exit your vehicle, park it out of traffic lanes. Stay in your vehicle with your seatbelt on. Put your head below the windows and protect it with your arms and a blanket or cushions.
- Outdoors – Shelter in a substantial building. If no shelter is available, lie face down on low ground guarding the back of your head with your arms.
- Keep your family together in a safe location and wait for emergency personnel to arrive.
- Stay away from power lines, downed trees, and puddles that could hide live wires.
- Watch your step to avoid sharp objects.
- Stay out of heavily damaged structures, as they may collapse.
- Do not use matches or lighters in case of leaking natural gas or fuel tanks.
- Listen to your radio for information and instructions.
Tornado survival kits
Because tornadoes can develop rapidly from a thunderstorm, it is crucial always to be prepared for them. Prepare for a tornado by investing in a tornado emergency kit.
Basic disaster survival tools:
- Long storage food
- Breathing protection
- First aid
- Sanitation & hygiene
For safety and shelter:
- N-95 respirators (face masks)
- Emergency thermal blankets
- Emergency ponchos
- Roll plastic sheeting
- Roll duct tape
For turning off utilities and other tasks:
- Can opener
- Bottle opener
- Knife blade
For communication and light:
- Metal whistles with lanyard
- AM/FM radio with two sets of batteries
- Flashlight with two sets of batteries
- 12-hour light sticks
- LED Safety Signal
- Waterproof document pouch
For hydration and nutrition:
- 2-gallon water bag for drinking and hygiene
- Food bar
- Emergency water pouches
- Water purification tablets
- Food (at least a three-day supply of non-perishable food)
- Paper cups, plates, paper towels, and plastic utensils
For medical, hygiene, and sanitation needs:
- Personal First Aid packet
- Family First Aid kit
- Biohazard bags
- Toilet paper roll
- Moist towelettes
- Feminine supplies
The damage tornadoes cause can happen in a matter of seconds. They frequently cause fatalities and devastate homes, businesses, and entire neighborhoods.
Although the most violent tornadoes can wreck and blow away almost any house and anything within it, extremely violent tornadoes are rare. Most tornadoes are much weaker. You can survive a tornado if you follow safety precautions.