Sun Halo Arc

This sun arc probably would have been a full halo if not for the lower altitude cumulus clouds seen toward the top of this image. The sun's interaction with high altitude cirrus clouds creates this type of phenomenon. Both images look southwest from Bowman Woods Park in Cedar Rapids, Iowa. The pic above was captured at 1:56 pm CDT, Saturday, July 30, 2022, the pic below one minute later. Air temperature was 81 degrees F, dew point 61 degrees, humidity 50%, and the wind was out of the southeast. Nikon D7200 DSLR camera.

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Forecasted Severe Weather for NE Iowa Remained at Arm's Length

An Enhanced Risk by the Storm Prediction Center (SPC) posted for north and northeast Iowa on Saturday July 23, 2022 hinted at a good opportunity for a possible intercept. A cold front behind very hot and humid conditions created the potential for "significant" severe weather later in the afternoon/evening. Shown above are the SPC categorical, tornado, hail and wind outlooks for the day. With my gear all packed and ready to go, I departed for northeast Iowa around noon in anticipation of a storm encounter via Highway 13. Storms were already approaching the Rochester, Minnesota area.

1:20 pm CDT. First stop (with a view) to check on the northern storm's progress. Would they begin to track southeast and cross the border into Iowa? The panoramic image above looks northwest from Chicken Ridge Road, about a quarter-mile west of Highway 13, and about 2.5 miles south of Elkader, Iowa in Clayton County. Skies were beginning to darken. Highway 13 is visible at background right as it continues north.

1:37 pm. Second stop. Image looks northwest at stormy skies as seen from County Road B65 (205th Street), about .4-mile west of Highway 13 and about 2 miles south of Farmersburg, Iowa in Clayton County. The storms were skirting the Minnesota/Iowa border but as of yet not dipping south. I had originally anticipated staying put here for their arrival. iPhone 11 camera.

1:43 pm. Looking north. My vehicle in the foreground.

Radarscope image corresponding to 1:44 pm. Line of storms in south-southeast Minnesota, tracking ESE. Note the tornado-warned polygon in the Rochester area. The target icon at lower right indicates my location.

1:46 pm. Wild flowers in the foreground with stormy skies in the background. It soon became apparent this position was going to be too far south for an intercept, so I resumed north on Highway 13. I was already a bit past my "60 mile radius solo maximum distance from home policy" by the time Highway 13 ended at the US Highway 18/52 junction. I was not prepared to follow the severe storms into Minnesota, which were still another 35 miles distant and staying north, so I turned west on US Highway 18 toward West Union, Iowa. The intercept attempt was over.

3:14 pm. Tornado warnings were squawking on my weather radio for southeast Minnesota at this moment, almost in taunting fashion. This image looks north while westbound on US Highway 18 east of Postville, Iowa. The tornado-warned area can be seen at far right, toward the northeast. At West Union, Iowa it was Highway 150 south and toward home. The far north advance gamble had not paid off. All told, the trip covered about 185 miles, all without much to speak about. It happens! Nikon D7200 DSLR camera.

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Morning Thunderstorms Move Through Cedar Rapids

 

A line of severe storms moved through Cedar Rapids, Iowa during the morning hours of Monday, July 11, 2022. The panorama image captured at 5:30 am CDT (above) stretches from west (left) to east (right) as seen from 33rd Avenue at 12th Street SW. Darkening skies are seen at left, while last remnants of brilliant skies are in the east.

5:45 am. Mammatus clouds on the front edge of the approaching storm looking southwest.

Radarscope image corresponding to 6:01 am. My location is shown as the blue target icon.

6:07 am. Looking west. Shelf cloud beginning to emerge along the horizon.

6:08 am. Looking west.

6:09 pm. Panorama looking west. Shelf cloud becoming more prominent.

6:09 am. Looking southwest. High winds, lightning and heavy rain would ensue in just minutes. iPhone 11 camera.

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July 3, 2022 Fireworks

The following pics are from a private fireworks display on the evening of Sunday, July 3, 2022, as seenfrom a location in rural Shueyville, Iowa. The above image, and the one below, were combined in StarStax2 to create the image at bottom. This image was captured at 10:15 pm CDT and is a 4 second exposure at f/2.8, ISO 125, 11mm focal length.

10:18 pm CDT, and is a 2.5 second exposure at f/11, ISO 125, 11mm focal length.

Combination image. Nikon D7200 DSLR camera. Tokina 11-16 mm f/2.8 lens.

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Derecho 2.0

 

Storms began forming in the state of South Dakota during the morning hours of Tuesday, July 5, 2022, and began picking up steam by late morning. By early afternoon storms began forming a powerful linear state, with hail and wind speeds reaching 100 mph--the early stages of yet another derecho. Severe thunderstorm watches went up for NW Iowa at 1:40 pm CDT and 3:50 pm for central Iowa. As storms advanced eastward, the Storm Prediction Center (SPC) upgraded an Enhanced Risk in SE South Dakota and NW Iowa to a Moderate Risk, valid from 3:00 pm CDT (above). 

4:35 pm. Severe Thunderstorm 440 is posted for eastern Iowa.

Radarscope image 4:46 pm. Storms entering NW Iowa are starting to form the classic derecho signature (left), and at the same time a boundary layer-induced line of storms are popping up in NE Iowa, SW Wisconsin and northern Illinois (right). 

6:09 pm. Active radar signature. Well-formed derecho at left. Note the tornado warning near Crystal Lake, Illinois at far right.

6:11 pm. Impressive reflectivity image of the derecho, packing winds up to 100 mph, just west of Fort Dodge, Iowa.

6:20 pm. Large picture of storms in Iowa and Illinois.

6:59 pm. Looking west over the Collins Aerospace facility from Volley's on Blairs Ferry Road at the distant edge of the storm, located just west of the city of Ames and central Iowa. iPhone 11 camera.

8:51 pm. Set up now for spotting operations at Noelridge Christian Church (42° 2'59.42"N, 91°38'26.65"W) in Cedar Rapids, Iowa. Looking west. Distant approaching storm exhibiting a striated shelf cloud appearance.

8:55 pm. Shelf cloud/gust front now dominates the horizon. My spotting vehicle is in the foreground. iPhone 11 camera.

 

9:00 pm. Panorama of shelf cloud as it grows ever nearer. 

9:00 pm. Same image (less wide).

Radarscope image corresponding to 9:01 pm, with my location shown as the blue target icon.

9:02 pm. Shelf cloud looking due west.

9:04 pm. Looking southwest. Leading edge of shelf cloud is brightened by lights from a nearby commercial area.

9:04 pm. Looking north at leading edge of approaching gust front. 

Radar image for 9:04 pm. White arrow points from my position to a tornado-warned area just east of Independence, Iowa in Buchanan County.

9:05 pm. Image corresponding to radar above it. Note the pronounced striations in the shelf cloud, the tornado-warned lowering behind the taller tree in the distant background, and the possible clear slot at lower left. A clear slot is an intrusion of drier air from Rear Flank Downdraft (RFD). I estimated and reported maximum wind speeds at this location of up to 70 mph. At 9:15 pm I witnessed flashes from an unseen substation to my northwest, resulting in an immediate power outage to the neighborhood. Nikon D7200 DSLR camera.

Storm reports from KGAN Channel 2 website.

This storm met the National Weather Service criteria for a "derecho." A derecho is defined as a long-lived wind storm producing damage over a swath of 400 miles in length. Derechos produce wind gusts of 58 mph or greater with frequent gusts of 75 mph-plus.

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Independence Day Provided Other Sparks

I had already settled in for the evening while abundant shrieks and bangs of Fourth of July celebrations were going on outside of the house on Monday evening, July 4, 2022. Not for long. My weather radio alarm sounded around 8:30 pm, prompting me to quickly check radar. The alert was for a tornado-warned cell occurring in Fayette County, located about 55 miles to the north-northwest and tracking southeast. Too far to intercept at this time of the day, but it occurred to me that it might be possible to catch a glimpse of it from the park behind our house. Sure enough, there it was, peeking through a gap in other clouds, beautifully illuminated by the setting sun and laden with mammatus within its anvil. The above image looks toward the storm as seen from near Bowman Woods Elementary School in Cedar Rapids, Iowa at 8:48 pm CDT.

Similar capture at 8:50 pm. For several minutes I had to continually wipe the lens of my camera as it kept fogging over due to atmospheric conditions (85 degrees F, dew point 77 degrees, relative humidity 77%). Nikon D7200 DSLR camera.

Radarscope reflectivity image from 8:50 pm, corresponding to the photo above it.

Echo tops graphic for 8:50 pm, showing cloud elevations surging to 55,000 feet. As the storm continued to track southeast and the sun went down, there were plenty of lightning flashes emanating from it--a natural display of Independence Day sparks!

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