SIOUX CITY, Iowa (KCAU) — We are on to the fourth day of Severe Weather Awareness Week here at KCAU 9, and today we talk about one of the most frightening and dangerous types of severe weather seen in this part of the country: tornadoes.
Tornadoes are formed from strong lift in a thunderstorm that flips the rotation vertically. This is caused by change in wind direction between the surface and upper levels. A change in wind direction with height causes horizontal rotation. The definition of a tornado is rotating column of air stretched from the base of the cloud, all the way to the ground. However, it must touch the ground to be considered a tornado. This also can be verified by swirling dust or debris at ground level.
This is most common to occur in the spring and summer months, however can occur anytime of year (but very rare in the winter). Tornadoes are rated on a scale called the Enhanced Fujita scale (EF scale), from EF0 to EF5, where EF0 is the weakest, and EF5 is the strongest.
An EF0 tornado has a wind gust of 65-85 MPH, where shingles can be blown off, gutters can be damaged and branches get broken off trees. An EF1 has a wind gust of 86-110 MPH, where it will cause broken windows, damaged doors, and mobile homes to be overturned. An EF2 tornado has wind gusts of 111-135 MPH, and can cause roofs to be torn off, mobile homes to be destroyed, and large trees to be snapped. An EF3 has wind gusts of 136-165 MPH, where entire stories of homes are destroyed and significant damage is likely to occur to large buildings. An EF4 tornado has wind gusts of 166-200 MPH and well constructed homes are leveled, with cars thrown a very significant distance. Finally, an EF5 tornado, which is the strongest of more than 200 MPH, will likely cause well constructed homes to be swept away, and trees to be completely debarked.
If a Tornado Watch is issued, make sure to stay up to date with your KCAU 9 Weather app and NOAA weather radio, and make sure to take it seriously. When a Tornado Warning is put out, get to your closest shelter right away. Your best bet is in the basement or lowest level of your house, including a small interior room or under your stairs. Go somewhere that you have anything heavy and big that can help provide your with extra buffer between you and the tornado. If you live in a mobile home or trailer park, and receive a Tornado Warning, this is even more important that you get to somewhere more substantial, where putting yourself near as many sturdy walls will be your best bet in this situation.
During any severe weather event, make sure you tune in to KCAU 9 News for the most up to date and accurate information. Make sure to download the new KCAU 9 Weather app, as it sends you alerts for your current location, and best of all, it’s free! Make sure you also have a NOAA Weather Radio, as it is a good tool to keep you ahead of the storm 24/7.
Stay with KCAU 9 News for Severe Weather Awareness topics throughout the week and get the local forecast any time right here.