Severe Weather in the Northern Plains
There's been notable severe weather in the northern Plains and Midwest over the past two days. I'll start by discussing the severe storms that went through the Midwest.
As of 930 PM PDT, there were 2 tornado reports, 51 hail reports, and 317 reports of damaging straight-line winds. The strongest wind report I saw was 90 mph at La Porte, Indiana, and the airport weather station at Haines, MI reported a wind gust of 79 mph. Here is a plot of the storm reports.
Plot of storm reports for June 18, 2010 from the Storm Prediction Center.
Two large storm complexes are responsible for the reports, and it's unusual to see two such systems relatively close together.
The radar composite shows that both systems were squall lines. The eastern system is dying, there aren't many convective cells at it's leading edge. The western system (the one near Chicago) is fully mature with vigorous convection at it's leading edge.
Video taken during the squall's passage through Chicago.
On the day before, there was a tornado outbreak in North Dakota/Minnesota. There were 66 tornado reports, 108 reports of damaging winds, and 75 hail reports. At this time, there are 3 deaths and at least 17 injuries associated with the tornadoes in Minnesota.
Plot of storm reports for June 17, 2010 from the Storm Prediction Center.
One storm passed near the Nexrad radar at Grand Forks, ND, giving this closeup view of the storm.
Base reflectivity from the Grand Forks, ND radar at 406PM CDT.
There are a lot of tornado videos from this day on the web, (search for June 17, 2010 tornado) here are a few that I liked.
Excellent close-up video of a multiple-vortex tornado.
Video of the Grand Forks, ND tornado
Video of a wedge tornado in southern Minnesota.