The National Weather Service, along with the Homeland Security and Emergency Management offices in Minnesota and Wisconsin have designated the week of April 20-24, 2009 as Severe Weather Awareness/Tornado and Severe Weather Awareness Week, in their respective states. This is a great time to get educated about the dangers of severe weather, and it is encouraged to go over safety plans to prepare yourself for when severe weather strikes.
In order to prepare for the severe weather season, statewide tornado drills will take place this afternoon, between 1 pm and 2 pm. There will also be a tornado drill conducted this evening, at 6:55 pm, but only for participating counties in Minnesota. In the local area, the counties involved in this evening tornado drill will be Wabasha, Olmsted, Winona, and Mower. These practice watches and warnings may be treated as the real thing, and is therefore a great opportunity to practice what you would do if faced with life-threatening severe weather.
**Should severe weather be present anywhere within Minnesota and Wisconsin on the day of the drill, the test watch and warnings will be postponed until Friday.
There will be themes being highlighted throughout the week, which include:
Please check out our Severe Weather Awareness Page to get important information about the above topics, along with other information to prepare yourself for the severe weather season.
Other links that may be of interest:
Today's Topic is Tornadoes
A tornado is defined as a violently rotating column of air in contact with the ground. It may not always be visible from the rotation within the cloud to debris being picked up along the ground.
Most tornadoes that occur in Minnesota and Wisconsin are relatively weak with wind speeds of 70 to 120 mph, but can certainly produce wind gusts higher than 200 mph, and in extreme cases these winds can exceed 300 mph.
In 2008, Minnesota experienced 43 tornadoes, but usually averages 24 tornadoes a year. Wisconsin experienced 38 tornadoes in 2008, however the average is 21 tornadoes a year.
May and June are the peak tornado months, followed by July and April. They can occur in any month though, and at any time of the day, even though the peak times are between 3 and 9 pm.
Tornadoes are ranked by the amount of damage they do, based on relative wind speeds. this is called the Enhanced Fujita Scale, and goes from EF0 to EF5. Most tornadoes in Minnesota and Wisconsin are EF0 or EF1. However, larger tornadoes are possible across the area. In June 2004, an F3 tornado touched down along the Iowa-Minnesota state line near Riceville, Iowa, and demolished several homes. A large EF5 tornado hit the towns of Parkersburg and New Hartford, killing 9 people on Memorial Day weekend in 2008. This was the first EF5 tornado in Iowa since 1976.
The best rule of thumb when a tornado is spotted, or a warning is issued for your area is to get underground. In a basement, find something sturdy to get under. If you have no basement, go to the lowest level of your home or business and move to an interior room like a bathroom or closet. Put as many walls between you and the storm as possible.
At schools, children should be moved into interior areas like smaller rooms, bathrooms, or hallways. Care should be taken not to select hallways that may become wind tunnels if exterior doors are blown off. Avoid large span rooms like gymnasiums, auditoriums, and cafeterias.
If you are driving and spot a tornado, drive away if you can clearly move at a 90 degree angle. If you have no escape path, leave your vehicle for a shelter or ditch. Get as low as possible and protect your head.
Most importantly, know in advance when tornadoes are expected. Many large tornado outbreaks, like the severe weather that has struck the southern states over the past few months, are well predicted. Listen for tornado watches and warnings and be prepared.