29. Stormy across the southern part of the state yesterday & more today.
This map (to the right), from the SPC, shows storm reports from yesterday - Saturday 6/7.
Unfortunately, the SPC's data for 6/7 is incomplete, at least for now, so I can't list initial tornado reports.
However, I do remember one report from central Columbia County and another from northeast Grant County. When the SPC corrects their problem, I'll update this information here.
Radar's look at Juneau County yesterday.
I was able to capture this screenshot (to the left) yesterday at 13:02 from radar KGRB, using Gibson Ridge's Level3 software.
This image shows Storm Velocity at base tilt (0.5 degrees). The rotation couplet is extremely evident where the strong winds blowing toward the radar site (blue-green) is located immediately adjacent to strong winds moving away from the radar site (magenta). This simply indicates strong rotation in the atmosphere at this elevation, which at 104 nautical miles from the radar site is about 12,600 feet above ground level.
I believe that this rotating storm did produce reports of tornadoes just after I saved this screenshot from central Juneau County. Regardless, based on the strength and persistence of rotation in this storm, the NWS La Crosse issued a Tornado Warning for this storm cell.
For those interested, Minneapolis' Metro Skywarn has a quick website that explains a little more about radar velocity - here.
Surface fronts today.
A front gradually sank southeast yesterday, providing lift and focus for rain and thunderstorms.
This map (to the right), from Wunderground.com shows current frontal positions at 7:08 this morning. Today, the front has stalled across Wisconsin, allowing for more rain and thunderstorms across the same areas that saw the action yesterday.
The forecast track of the front and low pressure calls for gradual movement southeast towards the Ohio River Valley, slowly pushing the heavy rain out of the area. However, rainfall amounts have already been extremely heavy in some locations, prompting Flash Flood Warnings across many areas in southern Wisconsin and northern Iowa.
Dry across the north, soggy across the south.
This radar image (to the left) shows the heavy rain across the southeastern half of Wisconsin at 11:04 this morning.