Labor Day Twister

Looking somewhat bland, the above graphic is the Day 1 Convective Outlook posting for the state of Iowa, updated at 11:30 am CDT, Monday, September 3, 2018. Little did I know six hours later I would witness up close one of the most dynamic and beautiful storm structures I've ever encountered--with a tornado--all on Labor Day, no less!

Weather in Iowa the previous two weeks had been one of long track training rain movements, so the little cell that popped up just east of Kellogg, Iowa around 1:40 pm, was paid no attention by most. Even at 4:00 pm (radar image above), the cell which had now increased in size did not differ considerably from the garden variety of rains to the north and east. I had been working on post-processing of recent vacation photographs with the television on in the background at 4:45 pm, when the TV emitted a squawk. Turning to it, a red screen broadcasted a "tornado warning for your area." Not quite believing this, I turned to my radar which initially showed nothing unusual. Then in an instant a red tornado-warned box popped up on the screen, with its most intense area located only about 18 miles to my northwest and moving east. I had not been prepared for this, so I quickly grabbed my "essentials"--handheld radio scanner, handheld ham radio and my Nikon D7200 DSLR camera (I forgot my weather radio). Assessing the storm's track, I decided to go east then north in hopes that the storm would hold its intensity by the time it reached me in the east. Traveling north on Highway 13 north of Marion, Iowa, I monitored Linn County ARES amateur radio traffic on my handheld. Just before 5:00 pm a spotter near Toddville, Iowa was reporting "nothing particularly menacing" visually from the storm, which was now approaching the town of Center Point. From my position northbound on Highway 13, I could see through a gap in the clouds what the Toddville spotter could not: a tall white cumulus tower sporting a vigorous updraft. There had to be significant severe weather under this tower and indeed a tornado had been on the ground 4 miles northwest of the town of Shellsburg around 4:40 pm.

Just after 5:00 pm I decided I was far enough north in relation to the approaching storm, so it was time to turn west, and did so on Central City Road (County Road E16), just south of the town of Central City. The above image was captured at 5:08 pm while westbound on Central City Road, just west of Highway 13. The turbulent nature of the storm, located now about 13 miles distant near the town of Center Point, is visually evident.

About 2 miles farther west, I found a stationary spotting location on Sutton Road just north of the intersection with Central City Road in north central Linn County. This image looks southwest at 5:13 pm. A wall cloud with a very low cloud base has come into view. I could still hear ARES Net traffic on my handheld ham radio, and with the wall cloud in view I attempted to make a report. I would be frustrated by about a dozen attempts in the next half hour to report the severe weather in this manner as apparently no one heard me. I was successful with three cell phone communications to the National Weather Service in the Quad Cities--at 5:13 pm, 5:35 pm and 5:43 pm.

5:13 pm. Similar image. Note the significant updraft in the distant background. I found myself tempting fate by staying outside my vehicle amid the CG lightning in order to get the good shots.

5:26 pm. The storm nears. The dynamic storm structure I had hoped for is not only holding but evolving. The wall cloud was vigorously rotating and was being fed by a fast moving inflow cloud (lower right). The ominous churning tornadic cell was moving east a little to my south, so I found myself as a northern observer--not the optimum situation but still amazing as it would unfold.

5:31 pm. Panorama looking WSW.  A more complete view of the storm cell from this spotting location on Sutton Road at Central City Road, about 2.3 miles west of Central City.

5:33 pm. A closer view of the wall cloud and inflow cloud. At this point stirrings of a lowering can be seen under the very low-based wall cloud.

5:33 pm. Another all-around view from a panoramic perspective.

5:34 pm. A zoomed-in view under the low cloud base, showing a ragged lowering.

5:35 pm. A striking closeup of the storm, with its inflow appendage at right. The center of this tornadic cell was now sliding closer to my south.

5:37 pm. A closeup of the inflow feeder cloud.

5:39 pm. Leading edge of the storm sliding south but about to overrun my position on Sutton Road at Central City Road. Winds were increasing to around 50 mph. At this point, it was obvious the houses and the hill in the background of this image were obscuring my line of sight, so it was time to make the decision to proceed south over the hill on Sutton Road (background), closer to danger but with a better picture of the storm.

5:42 pm. Clear of the hill on Sutton Road, and about .22-mile south of Central City Road. I immediately noticed to my southwest a funnel cloud and fire off this shot from inside my vehicle. Initially I thought this just a funnel, as the condensation cloud does not appear to be on the ground, but later image inspection shows rain circulation on the ground around it indicating that it was probably already a tornado.

5:42 pm. Similar view, with the tornado having advanced a little farther east (toward the left in image). The rain-wrapped ground circulation is evident.

5:42 pm. Similar view. Looking south on Sutton Road. Still inside my vehicle.

5:43 pm. Now outside my vehicle. My first still shot after firing off a short video clip. The funnel is now dipping fully to the ground, making it a full-fledged tornado.

5:43 pm. A no-doubter tornado now. Very powerful rain curtains swirl on the ground around the vortex. The tornado was about a mile to my south.

5:43 pm. Fully condensed funnel. This tornado was a cyclic spinup from the system that produced an earlier longer-lived EF1 tornado northwest of the Alburnett, Iowa (5:29-5:36 pm).

5:43 pm. Slightly zoomed-in view of the tornado. Note the perched bird on the power lines at left, apparently oblivious to the proceedings.

5:43 pm. Condensation funnel lifting from the ground. The strong rain curtain circulation beneath it continues to persist. The condensation funnel was fully on the ground for only about 20-30 seconds. Moments after I captured this image I returned to my vehicle. Having captured the images I needed, I began making a tornado report via cell phone to the National Weather Service. While doing so, I became aware of an EMT at my driver's side window who apparently regarded me as a "yahoo." At first I thought he was going to ask me what I had seen, but instead interrupted my conversation with the NWS dispatcher and told me in a stern voice that, "You need to get out of here immediately because a tornado is in the area." I had been oblivious to the myriad light-flashing EMA truck parked directly behind me. The truck did not budge until I moved, so I packed it up and headed back to Central City Road--which is what I was going to do anyway.

5:48 pm. Pausing at the southeast corner of Sutton Road and Central City Road. My vehicle was now being blasted by driving rain and RFD winds. This image looks east through my open passenger side window and captures the retreating storm, still producing tornadoes as it tracked in that direction.

5:45 pm GOES 15 visible satellite image of the lower half of the state of Iowa, with arrow pointing to the storm cell.

5:49 pm Radarscope image of the tornado-warned cell and my position (blue target icon).

A NOAA radar image from 5:50 pm, with my position shown by the target icon.

Weather.US images corresponding to 5:50 pm. Clockwise from upper left: Base Reflectivity, Storm Tracking, Vertically Integrated Liquid and Echo Tops. Target icons are my position. The classic hook echo images in upper images are evident.

5:57 pm. Looking back toward the northeast while southbound on Highway 13 and heading home.  The still potent storm cell is tracking eastward in the direction of Prairieburg and Monticello, Iowa.
An amazing experience from a totally unexpected severe weather event...and this Labor Day tornadic storm played out virtually in "my own back yard!" (See also my YouTube video of the event: 09032018LinnCoTornado)