Tornado Alley, Tornado Facts, And How They Form

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Tornadoes occur mostly in the United States. On average, 1,200 tornadoes cause 1,500 injuries and 65 fatalities per year in the U.S. (source: spc.noaa.gov)

Here’s more about “tornado alley”, tornado facts, and how they form:

 
Also, a question for you…

For those who live with the threat of tornadoes, do any of you have a specific storm shelter integrated with your home or property? If not, what are your preparedness plans if a tornado is approaching?


 

Where is Tornado Alley?

Tornado Alley is an area of the United States where tornadoes are most frequent.

Although the official boundaries of Tornado Alley are not clearly defined, its core extends from northern Texas, Oklahoma, Kansas, into Nebraska.


source: Wikipedia.org

Note: Tornadoes don’t form just in tornado alley!

Important!
Midland WR120-EZ NOAA Weather and All Hazard Public Alert Radio

 

Where do Tornadoes form in the United States?

The following map of tornado activity in the United States is a summary of recorded EF3, EF4, and EF5 tornadoes between 1950 – 2006.

 
Related: Tornado Season

 
Historical Record of Tornado Tracks (1950-2011)
tornado-tracks
Image: uxblog.idvsolutions.com
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Tornado Facts

source: NOAA National Weather Service

 
A tornado is a violently rotating column of air extending from a cumuliform cloud, such as a thunderstorm, to the ground.

Tornadoes may appear nearly transparent until dust and debris are picked up or a cloud forms within the funnel.

The average tornado moves from southwest to northeast, but tornadoes can move in any direction and can suddenly changer their direction of motion.

The average forward speed of a tornado is 30 mph but may vary from nearly stationary to 70 mph.

The strongest tornadoes have rotating winds of more than 200 mph.

Tornadoes can accompany tropical storms and hurricanes as they move onto land.

Waterspouts are tornadoes that form over warm water. Water spouts can move onshore and cause damage to coastal areas.

Tornadoes can occur at any time of day, and any day of the year.

88% of all tornadoes are weak, producing EF0 or EF1 damage and last 1-10 minutes.

11% of all tornadoes are strong, producing EF2 or EF3 damage, cause nearly 30% of all tornado deaths, and last 20 minutes or longer.

1% of all tornadoes are violent, producing EF4 or EF5 damage, cause 70% of all tornado deaths, and can last longer than 1 hour.

 

The Enhanced Fujita Scale

EF0 (65-85 mph)
EF1 (86-110 mph)
EF2 (111-135 mph)
EF3 (136-165 mph)
EF4 (166-200 mph)
EF5 (Over 200 mph)

 

How Tornadoes Form

source: “Thunderstorms, Tornadoes, Lightning…” Preparedness Guide (NOAA)

Step 1. Before thunderstorms develop, winds change direction and increase in speed with altitude. This creates an invisible, horizontal spinning effect in the lower atmosphere.

Step 2. Rising air within the thunderstorm updraft tilts the rotating air from horizontal to vertical.

Step 3. An area of rotation, 2-6 miles wide, now extends through much of the storm. Most tornadoes form within this area of strong rotation.

 
Related: 10 Tornado Signs

 
I do not live in a region where tornadoes form very often. For those of you who do, I am curious to hear about your own experiences. Also, do any of you have a specific storm shelter integrated with your home or property? If not, what are your preparedness plans if a tornado is approaching?

I hope that you all at least have one of these:
Midland WR120-EZ NOAA Weather and All Hazard Public Alert Radio

31 Comments

  1. We have a basement to go to if an extreme storm should hit. Tornadoes are very uncommon where we live, but several years ago we had what was called a microburst. It knocked down a path of trees less than 1/4 mile in length. When we looked out our picture window, we just saw a wall of white. Could not see anything beyond 12 inches from the window. No green, nothing, just white. If we had known at the time, we would have been in the basement.

  2. We don’t have tornadoes up here but we are right on the path of the jet stream with winds over 70mph. And then there are dust devils-dry land tornadoes which can be quite destructive. When I lived south of Tucson one took off our metal patio roof and threw it over our house roof. Also the micro-bursts in Tucson acted as destructive as tornadoes.

    1. Unless I’m misreading your post, the Jet Stream is not the 70+ winds your experiencing. The Jet Stream is located at between 30,000 and 52,000 above sea level.

      1. no I don’t live that high, but the winds do mix down causing us to be very windy.

  3. Where I live now tornados are not a threat. I grew up in the thumb district of Michigan, rural area but tornados were possible, not frequent and we had the tornado seasons. I recall being carried by my father as he ran across neighbors yards getting to a neighbors basement since we didn’t have one. My mother and older brother hot footing it in front of us; lasting impression on me being so young. I can still see it vividly, mid-day black sky, roaring due to a close tornado that never touched down. Police rolling by, loud speaker stating seek shelter now tornado warning. The town noon siren going non-stop.

    I have also seen the lime green sky in the early morning, opened my apartment curtains with the morning coffee and went “Whoa, that’s not right”. Turned on the radio that said get to shelter now, everyone in the apartment complex running in their PJs to the laundry room in the basement. Tornado touched down 1/2 mile or so away. Lucky.

    So, I check the weather conditions every day and always study the sky, when the threat of severe weather occurs I’m ready to roll to the basement, no hesitation, no debate. To me, there is nothing as eerie as the calm before the storm, everything goes still; wind, birds it all just stops, either all hell breaks loose or it passes, still creeps me out.

    1. There have been a couple of micro bursts that have done a few blocks of damage but nothing major. We did have the Columbus Day storm (hurricane)in the early 60’s that did a lot of damage. The whole tornado alley thing gives me a queasy stomach.

  4. Scary stuff, i remember watching tornadoes forming while driving across the plains in Nebraska and eastern Co, was quite an eyefull, we were framing in Weld county, had just sheeted the roof on a house, and wrapped up because it was looking like a thunderstorm was coming, so got off the roof, next day we got to the site only to find the tops missing off all three of the houses we had just covered up,,,one of them the whole upper level was gone, all of a sudden made the low prices on those homes look not so attractive

  5. Born and raised in Cincinnati Ohio, and do remember when my father build our ‘new’ home when I was 7 he build a ‘tornado room’ solid concrete with a steal door that could be bared from the inside. Mom kept a few things in there ‘just in case’.

    I now live in a place where there is little chance of the typical tornado, but as old lady said, we have ‘dust-devils’ here and can be rather destructive.

    “On rare occasions, a dust devil can grow very large and intense, sometimes reaching a diameter of up to 300 feet (90 m) with winds in excess of 60 mph (100 km/h) and can last for upwards of 20 minutes before dissipating.”

    Just another part of Situational Awareness…. Keep yar eyes open people.

    NRP

  6. Really interesting information! I don’t know that a tornado has ever formed where I live up here in the mountains. However, as soon as we travel down to the wide open valleys, it’s a different story. I have heard reports of a tornado once every few years. I have never seen one, and really have no desire to.

  7. I do have a question for someone that may know.

    Why is it that Tornados have a haltered towards Mobil home and Trailer parks?

    Seems every year there are dozen of them that get slammed by Tornados. It’s just amazing that more people are not killed by these natural killers when ya see the distruction.

    NRP

    1. I’ve heard it mentioned that tornadoes are Gods way of expressing his feelings about mobile homes? I have lived in a trailer a time or two when I was a soldier and always worried about them. It did get me to thinking that if I ever owned a trailer park I could name the streets. Whirlwind Way, Cyclone Court, Twister Ave and Dervish Drive are a few names that come to mind.

      Has anybody noticed how Tornado Alley has seemed to have shifted east? I grew up on the coast in Virginia and I think we had one very minor tornado growing up. I still have family there and now they have regular warnings and several events every year. So far nothing as large as the ones that occur all too often in the Midwest.

    2. The problem with mobile homes is the tie down under the unit. On the west coast we pour 6 foot wide by 24 in. thick concrete stripes with S.S. straps that come out of the mud and wraps around the frame rails. Now also you have to put earth quick jacks and not just CMU blocks with wood wedges like in the South. So most mobile homes are just a trailer parked on a lot setting on blocks with some skirting around the lower edge so you don’t see the wheels. Just like the 18 wheelers on the highway when a twister hits them they fly away.

  8. Been close twice, both times while visiting Florida. One was a block away and watched it go by (tore up the nearby shopping center in Cocoa Beach) and one went over the house (Cocoa). Not many basements around so I figured I may as well enjoy the show.

    Oh, and last year I drove past one (it was across the street) on its way to the Applebys I just left (Indiana)

    1. Lived in Cocoa Fl. when several came thru. One came thru a trailer park then thru my cousins service station. Strode U-Haul trailers everywhere.
      By the way, the state with the most reported tornadoes so far this year is Georgia. We see quite a few but now usually as strong as the mid-west.

  9. I’ve lived my entire life in tornado prone areas. I’ve seen many as they were forming and watched from a distance while they did their destruction. It is an awe inspiring display of raw power, especially the huge wedge tornadoes covering 1/2 mile diameter paths.

    Most of the deaths from tornadoes come from debris hurtling through the air a speeds of 100+ miles per hour. Survival is predicated on your ability to be shielded from these projectiles.

    When I built my retirement home, I built a “safe-room” in the center of the home that is actually a reinforced walk-in closet. The wall studs and ceiling joists are on 12″ centers instead of the standard 16″. These are covered by 3/4″ plywood and 1/2″ drywall both on inside and out. Barring a direct hit by a F-4+ tornado, I have faith these walls plus the exterior walls and brick will be enough protection from flying debris. All family members have an over-sized, jumbo pillow on their bed to grab prior to going into the safe room, for added head protection.

  10. ive been around for better than 60 years and over that time in this area you do one of two things when bad weather hits you either hole up right where your at or you RUN YOUR ASS OFF the worst we get around here is bad blizzards we HAVE some NASTY thunder storms MAYBE now and then some micro bursts but VERY seldom some ef0

  11. I lived in tornado alley for most of my young adulthood, now moved a bit west. We had a shelter that I would have to go in by myself when I got off the bus from school as no one else was home. I was very frightened. Tornado’s love to form in the late afternoon. Almost all homes had either a basement or separate shelter.

    I was a very young girl when a particularly nasty one hit downtown Lubbock, TX where I then lived. Tall buildings twisted around, lots of destruction. Mud permanently stained into walls, trucks thrown around like toys. Glad I don’t have to deal with that anymore!

  12. I live in Indiana, which has more tornadoes per square mile than almost any other state. (I think it is #1). I have experienced dozens of tornadoes in the area and have been in buildings damaged by them twice. As law enforcement, most od us are trained storm spotters. We are out in the storm relaying path information to Emergency Management. At home, we go into the basement, which us stocked with supplies.

  13. Being a native of northeast Texas, I have seen numerous “dust devils”. I’ve experienced one Ef-0. These occur when overheated air on the surface rises rapidly causing a vortex filled with dirt, dust, and debris, sucking it high up into the air.

    The largest I experienced and was actually caught up in was while at “summer camp” at North Fort Hood, Texas in the Army National Guard. It began in the motor pool area of the “cantonment area” as a common dust devil. This dust devil grew in intensity and size until it was about 100′ in diameter and several hundred feet high. It traveled into the Battalion encampment, leveling approximately 20 platoon sized tents and taking out 2 company headquarters tents. I sheltered in the cab of a 5 ton truck that shook to the point that I feared it would overturn. The sky was filled with paper worked sucked out of filing cabinets in the headquarters tents.

    It was impressive, doing quite a bit of damage. There was not a cloud in the sky, just intense heat causing the updraft and vortex. Paperwork lost was found several miles away.

  14. I was teaching 6th grade and it became totally dark outside. They announced over the intercom to open all windows. Suppose to equalize the pressure we were told. It just wasted time getting my students in the hall. I told my students in the hallway only God can help us in this. The roaring was so loud and everybody was crying and praying. The tornado came to the campus right outside my windows. It lifted up and went over my wing of the school. It touched back down on the other side where destroyed the bleacher and buildings by the football field. My room had 4 inches of water in it with books and papers floating around. The bulletin board on the opposite wall of the windows was washed down and destroyed. Thank God we were all alright. That same day about the same time a tornado hit a near by town and destroyed total subdivisions. There was only the concrete left of the brick houses. It also completely destroyed a mall and many businesses.

  15. Yep, We are all different, have different needs, occupations, priorities.
    These factors help to determine where we live and we do our best to adapt to the surroundings we live. With that said, almost every place that is livable has its dangers. Some prepare for those dangers more than others.
    Its the unexpected circumstances that sneak up and try to bit us in a–!!

    The unknown or untold coming events that concern me the most. Its been said by many that our Govt is using OUR assets to manipulate the weather and since its widely thought that the Govt also controls the MSM, well, just connect the dots!!

  16. About April 1995 Nashville was hit by several in one day. I worked on the outskirts of Downtown and you could see 5 small ones wrapped in rain going through the tall buildings. Glass and all manner of debris flying. Wow! Most of the folks I worked with went in the basement. I went outside away from the windows to look. The UPS man was making a delivery and a sheet of 4×8 plywood was levitating on the freight dock. It was over in no time. Torn the town up. What I noticed over the years in our area is the path is the same or similar every time we get a tornado. Even F1’s do plenty of damage.

  17. I live in Tornado alley. The dry line sets up just west of here and when that cold front comes down the Rockies and hits the humid gulf air… look out! Had a tornado near here around Christmas a year or so back… deadly.

    There aren’t basements here. My plan is to put all who can fit in the bathtub with a mattress or pillows for cover. I will watch the show. I am okay with it. Too many times there are tornadoes that scour concrete from the earth.

    When is is your time… It is your time to go.

  18. We have built a concrete storm/root cellar in our new house. We were going to have a concrete front porch so why not go on another 4 or 5 feet down with a door out of the basement. As far as tornadoes and trailer parks, i have been told tornadoes seem to follow low ground more than not, and many trailer parks are in low less desirable locations. I have not looked onto that at all.

  19. I moved to northern MN to get away from tornadoes. It doesn’t mean we don’t have high winds due to storms. I was in three tornadoes elsewhere and I don’t ever want to be near one again. They were not predicted and came up suddenly with no warning.

    One hit close to our primitive camp reenactment and the rain went sideways through the tipi, but it held up because of it’s funnel shape. Everyone else lost their tents and scrambled in the ditches. No warnings, no tornado watches on the radio.

    One was a water spout on Toledo Bend, and it was raining hard as a bitch as I went from Louisiana across The Pendleton bridge towards Texas. It picked up my Chevy Blazer and turned it around going back to Louisiana. Lucky I wasn’t cast into the lake. No warnings, no tornado watches.

    The last one hit in my back acreage in Pennsylvania where the funnel touched down. I was watching out my window on the mountain suddenly seeing trees uprooted flying above the tree line that was bent nearly horizontal. It went down the mountain and hit some small towns. No warnings, no tornado watches forecast on the TV, but after it hit, the weather man admitted they were caught by the surprise.

    I don’t rely only on the weather reports anymore as you can tell, I keep an eye on the sky, the clouds, and the barometer dropping.

  20. lived in tornado alley all my life. when we built our house I reinforced the closet under the stairwell to the basement with 2 X 12’s anchored to the floor. Have had several pass by over the years, but no damage so far. Mobile homes have several disadvantages, the worst being that the skirting blows off and air can get under it. They are built to flex as they move down the road and as the wind strikes it from different directions it flexes to far and comes apart. They are also not framed that well, many times the carpet and ceiling extend to the outside of the walls between the floor, studs, and rafters.

  21. Growing up in Nebraska, we always had our Tornado drills EVERY spring and also the Tornado sirens would be started up on my birthday EVERY year (March 21st, first full day of Spring!) and every Saturday until October. Crazy thing is, when I was a kid, all the graphics they’d show on the news is tornados picking up houses. Being a child of 4 maybe 5 at that time, I thought tornadoes started UNDER houses (don’t judge me LOL but please feel free to laugh LOL) All kidding aside, I’ve seen how powerful these storms can be and the fact that when stuff like that happens, it shows we are NOT in control at the moment but everything AFTER we need to be and we need to be critical thinkers while still being an emotional thinker.

  22. Yep. Our homestead is smack in the middle of Tornado Alley. We built our fantastic wine cellar in the best part of the basement, so I’ll be grabbing a cheese plate on the way down.

  23. We live in one of the map’s dark orange areas. Since we are East of the Mississippi the Tornado’s hit us at night. I guess these are the same storms that hit Kansas and OK earlier in the day. We have an interior room downstairs to use, but if a tornado hits the preps will be gone along with everything else.

  24. I have lived in the Midwest all my life. We have had a lot of tornado watches and warnings but we have not had any tornadoes hit the specific part of our suburb where we live. That said we HAVE had some close shaves. One time a tornado hit about a mile or two from where we were but thank god it was a small one. There was also one that hit about a half an hour away. When I was younger and we were at our grandparents’ house there was a tornado about three streets away but I didn’t see it. When I was little there used to be a lot of tornado watches and warnings but all of the real tornadoes just barely missed us. I don’t know if being one of the suburbs of Chicago had anything to do with it but I’m glad all we had were some close calls.

  25. I live in Bonham Texas, which is in tornado alley. We had lots of thunderstorms, including a nasty supercell. My daddy was out watering the garden, then he came yelling for us to get outside. There was what looked like to be a big dust devil about ten miles or so away. But that nasty old cloud had something coming. It produced a EF2 tornado, but luckily did not kill anyone. After that, I am tornado crazy!

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