Today’s topic is severe thunderstorms.
Thunderstorms are a common occurrence each spring and summer across the Midwest and Iowa is not immune. Each year sees hundreds of severe and non-severe thunderstorms. Thunderstorms can be extremely dangerous storms which may bring deadly tornadoes and lightning, damaging high winds and hail and can lead to flash flooding.
But many people do not pay as much attention to a severe thunderstorm warning as a tornado warning, saying, “it’s just a severe thunderstorm warning”. Meteorologists say that severe thunderstorms can be just as dangerous as tornadoes, perhaps more than some, it’s just that the winds are straight, not in a vortex. When you add in deadly lightning and hail, severe thunderstorms are quite dangerous, and some communities have now decided to activate their outdoor warning sirens not just for tornadoes, but also certain severe thunderstorms. Sheldon is one of those communities. Sheldon Emergency Management Director Walt Pruiksma says Sheldon’s outdoor warning system will be activated for tornado warnings, for severe thunderstorm warnings with straight-line winds forecast to be in excess of 65 mph and for any other emergency scenario affecting Sheldon.
The National Weather Service issues severe thunderstorm warnings for thunderstorms that are producing, or are capable of producing one of two weather events, says meteorologist and Lead Forecaster Chris Jansen with the Sioux Falls office.
A Severe Thunderstorm Watch means conditions are right for severe thunderstorms, and you should stay aware that a warning may be issued.
A Severe Thunderstorm Warning means National Weather Service meteorologists have determined that a severe thunderstorm is occurring or likely to occur. Warnings indicate imminent danger to life and property to those in the path of the storm.
Contrary to popular belief, a watch does not need to be in effect for a warning to be issued. If that happens, it just means conditions changed so quickly a watch wasn’t yet in effect.
Jansen says the weather service is also highlighting the fact that not all warnings are the same, and people need to listen.
Also, although lightning can be deadly it is not a criterion for what the National Weather Service defines as severe since even ordinary thunderstorms can produce a lot of lightning.