Wednesday, May 22, 2013

Tornado Folklore


By: Rocky Lopes

There is this thing called "folklore," which by definition can include legends, oral history, and popular beliefs. Folklore creeps into some of our thinking about severe weather, and may be something you have heard or have passed on to children. Let me share some "Tornado Folklore" that many of us have heard:

Photo from NOAA's Severe Storms Lab in Norman, OK
Folklore: Tornadoes only happen in "tornado alley" -- roughly defined as states in the Midwest from Texas to Minnesota.

Truths: While many strong tornadoes happen in the Midwest, they can -- and have -- happened in every state.

In many years, more people have died as a result of tornadoes that happen east of the Mississippi River than west of the river. Why? People who live west of the Mississippi River are more accustomed to having tornadoes, and have learned what to do, when to get to shelter, and how to be safe since they were a child.

Folklore: Tornadoes never hit cities.

Truths: Since the majority of land area in the U.S. is unpopulated, it appears as if tornadoes only strike rural areas.  The relative amount of area of a city with tall buildings is small compared with the city as a whole.

Unfortunately, we learned from many past events and as recently as May, 2013, that this belief isn't true. Just ask residents of Nashville, TN; Houston and Dallas, TX; Tuscaloosa, AL; Joplin, MO; or Moore, OK.

Folklore: You need to open windows in your house to equalize air pressure before a tornado may strike, to prevent the house from exploding.

Truths: Even with windows closed, houses have enough openings to vent the pressure difference in the time it takes a tornado to pass.  Some of the strongest thunderstorms have longer duration of low air pressure -- houses do not explode during those storms, so they won't during a tornado.  Opening windows is a dangerous and useless waste of time, and could actually be harmful to the house.

Folklore: Get into the southwest corner of your basement in case of a tornado.

Truths: Being underground is definitely safer than being above ground, but no particular corner of a basement is safer than any other.  Tornadoes can come from any direction. While it may appear that tornadoes in the Midwest always move from southwest toward to northeast, that is not always true. In fact, the EF5 Tornado that hit Oklahoma in May, 2013, traveled almost due west to east.

Folklore: Tornadoes do not cross bodies of water.

Truth: Tornadoes cross rivers regularly. The stream of tornadoes that occurred on April 27, 2011, crossed many rivers in 17 states.

Folklore: Once the tornado has passed, you can go out to inspect for damage.

Truths: Some strong storms can produce more than one tornado, sometimes several tornadoes at a time. On April 27, 2011, 362 tornadoes happened from two long lines of storms, creating the largest tornado outbreak in U.S. history.

Folklore: Our area doesn't have sirens, so we will not get notified in case of a tornado.

Truths: We are fortunate in Montgomery County to have many ways to get warnings in case of tornadoes or other emergencies.

Coming soon this year, FEMA's Wireless Emergency Alert (WEA) system sends notifications to WEA-enabled mobile devices at no charge. Using GPS technology, these notifications appear on mobile devices in areas under warning for a tornado or other life-threatening emergency.  Get more information about Wireless Emergency Alerts here.

You should also sign up for Alert Montgomery.  This system will send alert messages to any device you specify: cell and smart phones, email accounts, PDAs, and pagers. It's free, and you can adjust settings on it to receive alerts for life safety, fire, severe weather, accidents involving utilities or roadways, and crime.

NOAA Weather Radio will sound an alert for severe weather and other emergencies that are issued for Montgomery County. Once you set it, it will provide a tone alert with a radio announcement describing what is happening and what to do. You can buy one of these radios from electronics stores.

Providers of cable television service in Montgomery County, e.g., Comcast and FiOS, will broadcast notices from the Emergency Alert System (EAS) when issued by local authorities. EAS notices are broadcast on all channels simultaneously.


And follow MCFRS on Twitter.

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Rocky Lopes is an emergency management professional and has published numerous articles and information on disaster safety for some 25 years. He works at the National Weather Service Headquarters in Silver Spring, Maryland, and has lived in Montgomery County his entire life.

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