Early April means it is Tornado and Severe Weather Awareness Week, a time for all of us to remember ways to stay safe during stormy times. April weather in southeast Wisconsin can vary quite a bit this time of year, with snow and thunderstorms falling in the same week. And while we are not located in the heart of Tornado Alley, we still get our share of rough weather. The key to safety is information, and there are plenty of ways for us to get severe weather watches and warnings.
Remember that a "watch," either Severe Thunderstorm or Tornado, means that conditions are favorable for the development of severe thunderstorms. These severe thunderstorms always have the capability of producing tornadoes. A severe thunderstorm means winds 58 miles per hour or greater, _" diameter hail or larger, and/or the presence of a tornado. Watches are issued by the Storm Prediction Center in Norman, Oklahoma. They are located in the heart of Tornado Alley, a bulls-eye of tornado touchdowns in central Oklahoma. The "alley" extends south into Texas and north into Kansas, eastern Nebraska, Missouri, and Illinois. Wisconsin is on the northern fringes of this twister hotbed, but we still average 20 tornadoes per year.
The Storm Prediction Center (www.spc.noaa.gov) defines areas of concern each day, then monitors these areas for potential severe storm development. When they issue a watch, it usually covers several hundred square miles and is typically in effect for 4 to 6 hours. The local National Weather Service offices within the watch area are responsible for issuing severe weather warnings. These are issued if severe weather has been spotted or is indicated on radar. Our local National Weather Service office (crh.noaa.gov/mkx) is located in eastern Jefferson County near the town of Sullivan.
Their powerful Doppler radar scans the skies over southeast Wisconsin and checks for severe storms. They will issue tornado or severe thunderstorm warnings based on reports from severe weather spotters, law enforcement officials, or indications of severe weather on radar.
{INSERT_RELATED}So what is your best defense against danger from severe weather? Make sure you have a way to receive watches or warnings. Local TV and radio stations will pass this information on to you. But what if you aren't watching TV or tuned to the radio? What if a warning is issued in the middle of the night while you sleep? This is where the NOAA Weather Radio becomes invaluable. It is a radio tuned specifically to the broadcast from the local National Weather Service office. The office will broadcast weather information 24 hours a day.
During severe weather watches and warnings, they will issue a tone-alert that will sound an alarm on the NOAA Weather Radio. It allows you to hear a warning for your county anytime of day or night. The radios can be purchased at many electronics stores and range in price from $20 to $80. Make sure you get one with a battery back-up system (in case the power goes out during a storm) and a built-in alarm. The radio can then be turned on to "stand by" mode and will alert you only when watches and warnings are issued. You can even purchase a weather radio that will sound an alarm only for the specific counties you choose. To read more about the NOAA Weather Radio system, check out the following web site….
Many people think it's a little early to start thinking about severe storms. After all, our peak tornado month in Wisconsin is June, followed by July, May, and then August. But we have experienced a tornado in every month except February. Approximately 80% of Wisconsin tornadoes are classified as "weak" with wind speeds of 50 to 110 miles per hour. About 19% are "strong", having winds between 110 and 205 miles per hour. Fortunately only 1% of Wisconsin twisters are rated "violent" with wind speeds greater than 205 miles per hour.
Here are a couple of severe weather myths: the southwest corner of the basement is the safest place to be when a tornado approaches. That's not always true. Always go to the lowest level of the building you are in and get under something sturdy, e.g. a stairwell, work bench, a strong table, or if nothing is available, pull a mattress over yourself. The specific corner of the room is not important. You want to protect yourself as best you can against falling debris.
Myth #2: open windows a little before heading to a safe place. This will help equalize pressure between the outside and inside of the structure and keep it from exploding as super-low pressure from the tornado passes nearby. Forget the windows. It won't matter. Most structures are damaged or destroyed by the force of the wind. Get to a place of safety. That is the main priority.
