May 17 Iowa Severe Weather Threat

An Enhanced Risk severe weather potential for the state of Iowa was posted by the SPC on Wednesday, May 17, 2017. Tornado Watch 231 (above, left) was issued for the west two-thirds of Iowa at 12:05 pm CDT; then Tornado Watch 233 for NE Iowa (above, right) at 3:10 pm. I was on the road less than a half-hour later and selected a severe cell moving south-to-north in Johnson County (below).

My position for the photo--seen below at 4:30 pm--is shown in the radar image above at upper right. The lighter area of the storm cell in the image below is in the area of the arrow shown above.

The severe cell passed to my west (above) as I found a spotting position at 4:45 pm. My location was on 540th Street SW, a half-mile west of Observatory Avenue, and about 1.5 miles southwest of Hills, Iowa. The cell, which appeared to sport a funnel-like appendage, was about 10 miles distant.

When the Johnson County cell weakened below severe limits, I decided to head back north on US Highway 218/Interstate 380 to get into position to intercept a new line of severe storms to the west in Iowa County before 5:00 pm. This line had a NNE track. I then decided to travel west on US Highway 30, and as the storms neared, selected the driveway at the Youngville Cafe along Highway 30 in Benton County. The historic cafe is located just east of 24th Avenue, and about 3.6 miles southwest of the town of Newhall. The above image looks south at the approaching storm from behind the cafe at 5:48 pm. The fast moving storm was about 10 miles distant at this moment.

This panoramic image in the same location, but closer to the highway, distorts the actual much wider shelf cloud, giving it a wedge tornado-like appearance. At this moment--5:50 pm--the storm had neared to only 5 miles away. Less than ten minutes later, the storm blew over me, with winds estimated briefly at 60-70 mph. Pea-size hail and blinding rain followed. Returning home, I noticed a couple of utility poles askew and intermittent areas of small debris on the road. Nikon D7200 DSLR camera.

The radar image above corresponds to the panoramic image above it. The target symbol is my position, with the black arrow pointing toward the storm. White arrows indicate storm movement.