Rare SPC High Risk Day Impacts Johnson County Iowa With Tornadoes

This predicted upcoming storm system on the last day of March, 2023 was not going to be an ordinary one. This was evidenced by the NWS Storm Prediction Center's posting of an Enhanced Risk (Level 3, above), four days in advance on Tuesday, March 28. The area included large areas of Arkansas, Missouri, Illinois and my home, Eastern Iowa.

5:00 pm CDT, Wednesday, March 29. Forecasted Enhanced areas expanded.

7:00 am CDT on Thursday, March 30, the day before the event. The categorical outlook has been upgraded to a Moderate Risk (Level 4), and shows ominous areas for tornadoes, hail and wind. Pivotal Weather Graphic.

7:00 am CDT, Friday, March 31--day of the event. All areas have been expanded and energized.

9:05 am CDT. Email from NWS Quad Cities (DVN) Weather Forecast Office goes out to all area severe weather spotters from Warning Coordination Meteorologist Rich Kinney for an awareness "heads up."

11:00 am WeatherTap screen capture showing the dark red area of the Moderate Risk with numerous spotters located throughout, including myself.

11:00 am. SPC Mesoscale Discussion 390 goes out, with the expectation of a "Upgrade to tornado-driven High Risk (Level 5) to be issued at (11:30 am CDT)." 

 

High Risk (Level 5 of 5) is quickly issued, which includes portions of eastern Iowa and western Illinois. The Moderate Risk area is also expanded.

11:12 am. Screen capture of my home Tempest Weatherflow weather station, showing dew points approaching 60 degrees, falling barometer and strong southeast winds. 

11:16 am. SPC Mesoscale Discussion 393 for a PDS (Particularly Dangerous Situation) Tornado Watch likely to be issued in the next one to two hours. Areas included eastern Iowa, western Illinois and northern Missouri.

11:25 am. Satellite image showing large areas in Iowa of ample sunlight, creating atmospheric instability.

11:35 am. SPC four panel outlook, showing an area of High Risk now included in portions of Arkansas, Tennessee and Mississippi in the South.

11:41 am. Pivotal Weather High Risk map.

11:48 am. WeatherTap screen capture, showing the recent High Risk upgrade area (lavender). 

11:49 am. NWS Forecast Discussion.

11:57 am. PDS Tornado Watch 93 is issued for a large portion of Iowa, northern half of Missouri and western half of Illinois.

11:57 am. Seriously worded and colored issuance of forecasted "Major Severe Weather Outbreak Today and/or Tonight." Now I was in spotting interception mode. But where? The best bet was south of Cedar Rapids, deeper into the High Risk "danger zone." Going solo today, I did not think it prudent to travel too far in these conditions, so my initial thought was setting up spotting operations in the relatively nearby town of North Liberty in Johnson County. I departed Cedar Rapids around 12:10 pm CDT.

En route to North Liberty I of course changed my mind. The small town of Hills, just south of Iowa City had served me well in the past, with a wall cloud sighting on one occasion and a nearby tornado on another. Above, I approach the Hills, Iowa exit on US Highway 218 at 12:51 pm. The unstable atmosphere is evident with churning clouds seen to my south.

At my stationary spotting location at the Animal Haven Veterinary Hospital parking lot in Hills. I first asked permission from the proprietors to locate there. I had originally parked at the Casey's Convenience Store next door, but changed my mind. My vehicle mobile weather station is shown here at 1:16 pm, showing robust southeast winds, temperature of 69 degrees F, and a dew point of 60 degrees.

1:20 pm. Yours truly in a serious "selfie" pose from my spotting location at the veterinary hospital on Oak Crest Hill Drive SE in Hills, Iowa.

2:39 pm. Mobile weather station monitor, now showing 72 degrees F temperature and 64 degrees dew point.

2:51 pm. Gathering dark clouds to my southwest.

3:37 pm. Approaching supercell with mammatus on the leading edge of its anvil. The tornado from this storm impacted the town of Keota.

3:38 pm. Velocity radar capture showing rotation (left) and my location (lower right).

3:40 pm. West-looking vista of mammatus clouds, with US Highway 218 in the background. Note the inflow cloud feeding into the storm at lower right.

3:46 pm. Looking northeast at mammatus cloud formations. Many of the structures seen in this image would be severely damaged by the arrival of another tornado, about one hour and 15 minutes later.

3:57 pm. Radarscope frame capture showing tornado-warned cell at left center, and my spotting location in Hills, Iowa.

4:07 pm. Radarscope frame capture. The storm has tracked farther northeast and is about to impact the town of Keota.

4:07 pm. Left edge of an EF4 wedge tornado, located about 30 miles distant, near the town of Keota along the Keokuk and Washington county line. This image looks southwest.

4:12 pm. Tornado is tracking closer to me now from the southwest. The lighter clouds seen among the dark mass of the tornado are rotating around it (from left-to-right in image).

4:12 pm. Similar image. Inflow cloud can be seen low along the horizon at left.

4:13 pm. Radarscope frame capture. The second storm cell (toward bottom) was severe-warned at this time but would eventually become the culprit that would spawn the EF2 tornado that struck Hills.

4:16 pm. Tornado panorama looking west.

4:16 pm. Inflow cloud feeding into the tornado (left center).

4:17 pm. Looking west at the tornado. By this time I had communicated its presence to the Linn County ARES Net via amateur radio, and verbally to the employees of the veterinary hospital where I was located.

4:22 pm. Radarscope frame capture.

4:27 pm. Tornado emerges from behind the line of foreground trees. I had to run across the road and along a fence toward the right (north) to obtain a better visual to confirm for spotting. The tornado was now a lower EF2 rating.

4:31 pm. Radar capture.

4:32 pm. Radar captures.

4:36 pm. Tornado panorama looking west.

4:37 pm. Layered convective clouds looking south. The Casey's convenience store is in the background. It was from this direction--and a bit toward the right--the second tornado would form and strike this very spot.

4:37 pm. Cell phone Emergency Alert.

4:39 pm. Looking east over the roof of the Animal Haven Veterinary Hospital at picturesque swirling clouds. It was around this time I made the decision that probably kept me from serious harm: I had my pictures and video (please see my 10 minute YouTube spotting operations video), so I wanted to head back north, partly to get closer to home, and partly to be able to continue to image the tornado to my west/northwest as I ran "parallel" to it. What I wouldn't know until I returned home was that this very location became heavily damaged by the second tornado, which hit about 15-20 minutes after I left. Was it a God thing that I made this decision?

4:43 pm. Heading back north on US Highway 218, just north of Hills. Tornado is at left, with elongated inflow cloud at right. But all was not well yet: What I absentmindedly disregarded was the fact that the highway direction south of Iowa City travels to the north/northwest, and the tornado was tracking to the northeast. This meant that at some point I would cross the storm's path. Nikon D7200 DSLR camera.

4:48-4:49 pm radar captures.

4:56 pm radar capture. Around 4:55 pm I had reached Coralville Lake on Interstate 380 when high winds and blinding rain swirled over the pavement in front of me. Estimated quarter size hail hit my vehicle and I began to notice random leaves fluttering down from high in the sky. I'm guessing I was inside RFD winds or possibly the outer circulation of a nearby tornado. Thankfully, I emerged from this area unscathed. 

4:56 pm. Tornado-warned areas stretching from Mt. Pleasant in the south to Waverly in the north.

Comparison images of structures just north of the veterinary hospital in Hills, looking north/northeast. Top image at 3:46 pm, about one hour and 15 minutes before tornado struck; bottom image (courtesy of KGAN TV2) in the immediate aftermath of the storm.

NWS service Overview of Tornado Outbreak and Surface Analysis map.

Tornado track maps for Eastern Iowa (left) and the Iowa City area. As of this posting, over 20 tornadoes touched down in the state of Iowa on this rare High Risk day. The towns of Hills, Coralville and Solon, all in Johnson County, reported significant storm damage.