Fast Intensifiers On June 24

A scattered cluster of small benign storm cells in eastern Iowa suddenly began to intensify around the Cedar Rapids area on the afternoon of Monday, June 24, 2019.  A hefty cell began entering my location in Hiawatha as the two radar images above show--the left at 2:27 pm CDT, and the right at 2:30. Driving heavy rain with 60-plus mph winds at that time prompted a report by me to the National Weather Service in the Quad Cities and minutes later the area just east of here went severe warned.

Above, the storm system continues east (background) as seen from Progress Drive and Martha's Way in Hiawatha at 3:01 pm. Mammatus can be seen in the cloud mass at left center. This was an iPhone 6-Plus camera capture.

By 3:15 pm I had found my way to Alburnett Road and Flight Drive in the Bowman Meadows housing development in Marion, Iowa. The above storm panorama from 3:17 pm spans from east (left) to south (right). This distant area was again severe-warned.

A radar screen capture closely corresponding to the above and below photos. My location is indicated by the target icon, with a line of sight arrow pointing to the distant updraft area residing about 50 miles distant, northwest of Davenport, Iowa.

3:17 pm. Looking southeast at the severe storm's updraft from Alburnett Road and Flight Drive in Marion.

3:18 pm. At nearly the same time, a weaker by still photogenic storm cell had also begun to form about 11 miles to my northeast (above).

3:23 pm. A zoomed-in view of the distant updraft of the departing severe-warned cell. By now the most intense part of this storm was about 55 miles to the southeast, and about 10 miles northwest of Davenport. Nikon D7200 DSLR camera.

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May 24 Hills Iowa Tornado Sequence Pics

Originally captured as video by my Nikon D7200 DSLR camera, the images above are created frame captures of that video. Using an approximate starting time of 6:48 pm CDT on Friday, May 24, 2019, each of the six EF1 tornado pics have a further time stamp labeled in seconds. First images show a wrapping horizontal vortex, while later ones exhibit a multi-vortex feature on the ground. My location was 540th Street SW, about 3.4 miles WSW of Hills, Iowa in Johnson County. The first image looks northwest while the last image is to my north. The tornado was about 2.5 miles distant.

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June 15 Multiple Rounds of Storms

Much of the state of Iowa was under a Storm Prediction Center (SPC) Slight Risk posting on the afternoon of Saturday, June 15, 2019 (above), and indeed storms began forming just after 1:00 pm CDT.

1:23 pm. Storm Prediction Center posts Severe Thunderstorm Watch #359 for much of Iowa.

I began to formulate an intercept plan with a target of two strong storms areas in Tama County. Because of its closer proximity to Cedar Rapids, I set out for the easternmost cell, located near Dysart, Iowa (circled area in the Radarscope image above, corresponding to 1:27 pm).

Above, I found a spotting location at 26th Avenue at 71st Street (E44), about .75-mile west of Newhall, Iowa. A non-severe storm, 14 miles distant and located between Elberon and Garrison, was approaching me from the northwest at 2:35 pm. Shortly after this time my attention shifted to another storm on radar, this one farther west in Marshall County and now severe-warned. In short order, I  chose to abandon this storm to pursue the new one.

2:55 pm. Westbound on US Highway 30 at 21st Avenue (V66), 3 miles south of Van Horne in Benton County Iowa. In the background at right a large updraft can be seen through foreground clouds. The severe storm cell was located about 32 miles distant, just east of Marshalltown. It was severe warned from 2:35-3:50 pm.

With echo tops on this storm cell billowing to 40,000 feet or more, I chose an advantageous spotting location--this one at the same location where I had monitored the eastern reaches of the July 19 Marshalltown tornado event last year. Above, the camera looks northwest at 3:15 pm from Highway V18 at 320th Street, just north of US Highway 30 in southeastern Tama County. Note the vigorous updraft at left. I chose to check in with the Benton County ARES (Amateur Radio Emergency Services) network frequency, in wary anticipation of incoming dangerous weather.

Radarscope image for 3:20 pm, with my location at the lower right.

3:22 pm. A larger view of the same scene.

Radar frame capture roughly corresponding to the photograph above it. My location is shown by the target icon at bottom right, with the black arrow pointing toward the most intense area of the storm. White arrows indicate the storm's track.

3:22 pm. Vertical capture of the updraft, sporting a beautiful overshooting top.

3:55 pm. Panorama of the storm, now visibly weakening. In fact, it had lost its severe warning five minutes before. I politely checked out of the Benton County ARES net and headed for home.

But the day's storms were not done yet. A new line of severe storms began organizing to the west of Cedar Rapids between the five and six o'clock hour. After adding spotting partner Billy Gant for a new intercept, I chose this location--74th Street at 30th Avenue (Highway 201), one mile south of US Highway 30 and three miles north of Norway, Iowa in southeastern Benton County--just in the nick of time. A shelf cloud from a quickly approaching gust front was bearing down upon us. Above, the camera looks west along 74th Street at 6:40 pm.

Radarscope image roughly corresponding the photograph above it, showing the severe-warned line of storms and our spotting position. Storm movement was due east.

6:42 pm. Panoramic capture of the same view.

6:42 pm. Looking northwest. Shown is the northern edge of the shelf cloud.

6:45 pm. Looking west down 74th Street at a possible forming and incoming funnel. Brief and weak tornadoes sometimes spinup along the leading edges of gust fronts such as this.

6:46 pm. The funnel cloud was looking more pronounced. It did not drop to the ground, but the ensuing rain sure did. Long lasting drenching rain followed us all the back home after we finally bailed out of this location. Wind speeds probably approached 60 mph here. A full afternoon/evening of volatile weather on this day to be sure! Nikon D7200 DSLR camera.

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June 12 Cedar Rapids Linear Storms

A (non-severe) line of linear storms approached Cedar Rapids, Iowa just before 6:00 pm CDT on Wednesday, June 12, 2019. Though not overly powerful, they were nevertheless aesthetic in appearance. The image above, captured at 6:07 pm, looks northwest over Bowman Woods Park in Cedar Rapids. The storm is less than five minutes away.

6:07 pm. Panorama version of the incoming line of storms.

6:08 pm. Rain saturation in the clouds is beginning to show. Wind speeds of 40-50 mph occurred as the storm passed through this location, including heavy rain and BB size hail.

College of DuPage GOES16 visible satellite image, corresponding to 6:01 pm. My location is indicated by the target icon.

Radarscope image corresponding to 6:10 pm. The storm was moving in a southeasterly direction.

An hour later another line of storms passed just north of my location. In the image above, thunder was rumbling from this storm at 7:23 pm. Panoramic view looks northeast from Boyson Road, just east of Brentwood Drive NE in Cedar Rapids.

Similar shot at 7:25 pm. Nikon D7200 DSLR camera.

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Another Expedited Intercept

At 4:35 pm CDT on Sunday, June 9, 2019 I was working on my computer, oblivious to the possibility of any kind of severe weather. The 8:40 am Storm Prediction Center (SPC) convective outlook maps for June 9 showed only the smallest probability for thunderstorms in my location (see target icons above). So when my wife approached me with the news she had heard from the radio at 4:34 pm: "There's a tornado warning," I was utterly confused. I thought she had meant for Texas or Oklahoma, and why would she be telling me that? Suddenly my home weather radio blared an alert, followed quickly by my cell phone notification. This setup was similar to the May 29 event, when there was very little time to prepare.

A line of storms had started forming around 3:00 pm in northeast Iowa, east of Decorah, and began moving southeastward with a track that would bring the southern segment just northeast of Cedar Rapids. The radar image above corresponds to the time of the tornado warning alert. The area of greatest intensity is circled, with arrows showing the storm's movement.

With the storm less than 20 miles away there was only time to pack my bare essential equipment for an intercept: my Nikon and GoPro cameras, and hand held weather and transceiver radios. The Radarscope frame capture above shows my mobile position to the tornado-warned storm at 4:54 pm.

The image above looks northeast at 5:00 pm while northbound on Highway 13 just south of County Home Road (E34). Billowing in the background is a cumulonimbus cloud spiking above 40,000 feet. The most intense part of the storm was located about 14 miles distant, about five miles northwest of Anamosa.

5:01 pm and eastbound on County Home Road (E34), just east of Highway 13 and northeast of Marion, Iowa. Zoomed-in shot of the anvil-topped cumulonimbus.

5:02 pm. Wide angle shot of the northeast sky while continuing east on County Home Road, about 3 miles west of Whittier, Iowa.

5:07 pm. Eastbound on County Home about 2 miles west of Viola, Iowa. A high precipitation core of the storm is seen at left.

5:08 pm. Now about one mile west of Viola. Heavy rain shafts are seen at right. The storm is moving from left-to-right in the image. Camera looks to the northwest.

5:09 pm. Eastbound on County Home Road at the western edge of Viola. A medium rotating wall cloud is seen above the background utility poles, with a possible forming funnel (lighter area) at center.

5:10 pm. At the intersection of County Home Road (E34) and Stone City Road in Viola. Rotating wall cloud can be seen low in the east, just above the tree line at right.

Radar frame capture for 5:15 pm as I was proceeding toward Anamosa on County Home Road. An arrow points toward the most intense part of this storm from my current mobile location (target icon). An EF0 tornado was occurring in this general area at this time.

5:16 pm. Eastbound on County Home Road (E34), about 1.5 miles southwest of Anamosa, Iowa, and .25-mile west of 223rd Avenue. The high precipitation area of the tornado-warned cell is just behind the tree line at left.

Base reflectivity (left) and velocity images corresponding to the time of the photograph above them. My location is shown with the white target icon. Arrows indicate the storm's track.

5:20 pm. At my stationary spotting position on 223rd Avenue in the Turkey Hollow II housing development, about 1.5 miles southwest of Anamosa. This image looks east. The storm sports a high precipitation core at left, a slowly rotating wall cloud at center and is moving away at around 35 mph toward the background at right.

5:27 pm. Panorama looking southeast from 223rd Avenue. Note the large precipitation area at left.

5:30 pm. Storm with a very impressive precipitation core.

5:32 pm. Looking southeast from 223rd Avenue at the departing storm. My eyes were probably deceiving me when I thought I saw faint debris rising from just above the tree line at left background and moving to the right; but it also could have been dirt kicked up by a truck driving through a construction area which was located in that direction. I could not report what I might have been imagining. (What was not imagination was the fact that three EF0 tornado touchdowns were confirmed on this day: 3:53 pm northeast of Winthrop, 4:24 near Prairieburg and 5:14-5:17 south of Anamosa.) With the passage of the storm from this position, it was soon time for me to "weigh anchor" and head for home.

5:47 pm. This image looks back east at the departing storm cell during a brief stop on a connecting intersection along US Highway 151 near Springville, Iowa. Nikon D7200 DSLR camera.

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