From a meteorite to a volcano to a dust devil it has been quite an interesting weather week. I received reports last Sunday from a couple people describing "tornado like conditions".
Since it was bright and sunny it was surely not a tornado but it was what we call a dust devil. One of the reports I received was from someone who saw this phenomenon in their backyard. The dust devil was strong enough to pick up their trampoline and move it! Since someone emailed me and asked me what a dust devil is I thought I would cover the weather fact for one of my topics.
A dust devil is a rare occurrence in Wisconsin but is more common out west in the United States. They occur mainly in dessert areas and have been reported all over the world. They form under sunny skies with light winds. A pocket of warm air begins to rise into cooler lower pressured air right above; this will be an unstable condition. When conditions are just right the column of air will begin to spin taking on a circular motion. It will eventually get stretched vertically thanks to a principle meteorologists call conservation of angular momentum. Typically they do not affect people or property because they are fairly small, don't last long and don't have the strength of tornadoes. They are usually 10 to 300 feet wide with a height of 500 to 1000 feet. They can reach speeds up to 60 mph or greater but are on average weaker. They normally only last a couple minutes although there has been reports of them lasting 20 minutes and greater.
Dust devils are classified as a storm event and should be reported to the local National Weather service office if spotted.
Have a fabulous week! Meteorologist Kristen Connolly