MADISON, Wis. --  Southern Wisconsin experienced two types of severe weather Friday evening. Impacts to power were minimal however, a dramatic supercell caught the eyes of many.

The first type of severe weather was a supercell thunderstorm which developed near Platteville around 3 pm. Our First Warn Queen B Radio Skycam caught a developing wall cloud looking southwest towards Dickeyville. The First Warn Weather team relayed this to the National Weather Service in La Crosse, prompting them to deploy storm spotters in Grant County.

That storm soon prompted a severe thunderstorm warning, shortly followed by a tornado warning in parts of Grant, Lafayette, and Green counties. A supercell thunderstorm is a rotating thunderstorm, and the whole thunderstorm is rotating from top-to-bottom.

First Warn Weather's Chief Meteorologist Alex Harrington says this is why many viewers sent in photos and videos that look like a “spaceship” cloud structure. “That’s the rotation being seen throughout the depth of the atmosphere in that storm,” says Alex.

You can view the many photos News 3 Now viewers sent in here.

That same supercell moved slowly through Dane County. The First Warn Weather Team caught the video of the wall cloud rotating over Lake Mendota. They passed images and video from the First Warn Edgewater Skycam to the National Weather Service in Milwaukee, which later prompted a warning with a "possible tornado" tag.

The second type of severe weather brought a line of destructive, straight-line winds also moved through areas near Platteville, along and south of the Wisconsin River Valley, and areas along and south of I-94, especially near the Wisconsin-Illinois state line.

Winds were reported up to 65 MPH near Potosi, 70 MPH in Lancaster, near 80 MPH along the state line, and another 80 MPH gust reported near Fort Atkinson.

Ahead of it was an impressive “shelf cloud,” which is commonly seen out ahead of a bowing line of straight line winds. The image below is a "shelf cloud" also captured by the First Warn Queen B Radio Skycam Friday afternoon.

The severe weather threat had ended across the WISC-TV viewing area, although an isolated severe thunderstorm with gusty winds cannot be ruled out, mainly east of Madison Saturday afternoon.

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