Under Severe Limits

A line of storms, stretching from central to northeast Iowa on Wednesday evening, July 12, 2017, produced two severe-warned areas around 5:30 pm CDT. The southern and westernmost was near Marshalltown, and the northern and easternmost near Oelwein. I chose the southwest option, and drove to it from Cedar Rapids via interstates 380 and 80. Above, a roll-type shelf cloud with scud is seen on the horizon at 6:34 pm while I was westbound on I-80, just about 1.5 miles east of the Amana exit (US Highway 151). Despite its ominous appearance, the storm had lost its severe tag by 5:45 pm.

Pulling off the US Highway 151 exit, I chose a widened part of the road about a quarter-mile north of I-80. This view looks NW at the approaching shelf cloud at 6:37 pm. The gust front was now about 5 miles distant.

Panorama of the same scene a minute later.

Northwest view of the shelf cloud from across the road at the same location at 6:39 pm. Nikon D7200 DSLR camera.

The atmospheric ingredients on this day were such to create heavy rain situations, and I ran into this in downtown Cedar Rapids on my way home--at one point nearly being unable to see the lane stripes on Interstate 380 ( a few minutes after the above GoPro Hero 4 video, in which this still was made).