A series of shortwave troughs traversing the northern CONUS brought unsettled weather to the area for the end of June. On the 21st, a stationary front was draped across northeast Nebraska into Iowa. Ahead of one of the aforementioned shortwave troughs, several rounds of strong thunderstorms developed near this frontal zone and moved across northeast Nebraska. At 8 pm on the 21st, radar imagery showed training thunderstorms had set up across central Nebraska. These storms moved into east-central Nebraska dropping 2 to 6 inches of rain across the Platte River Basin. As a result, minor flooding was observed along the Platte River in Dodge, Saunders, Douglas and Sarpy Counties. Further north in Knox County, additional rounds of thunderstorms brought flooding to the Ponca Creek, prompting emergency management to deploy sand bags. Flooding in these locations continued for several days before subsiding the 23rd.
Behind this first shortwave, a shortwave ridge moved out into the central Plains accompanied by a surface high pressure system. Afternoon high temperatures in the 90s and dew points in the mid and upper 70s brought excessive heat to much of eastern Nebraska and western Iowa the afternoons of the 24th and the 25th. Excessive heat was most widespread on the 24th, with heat indices across the entire WFO ranging from 107 to 120 degrees. Afternoon thunderstorms on the 25th mitigated excessive heat, though heat indices did hit 110 in far southwest Iowa. The Nebraska Department of Health and Human Services reported 80 heat related hospitalizations across the state during this period of excessive heat. While many of the 19 counties reporting these cases masked the exact number of hospitalizations in order to protect personal health information, it was released that there were 37 heat related hospitalizations in Douglas County, 13 in Lancaster County, and 7 in Sarpy County. The vast majority of these heat related illnesses (66.25%) occurred at work or while participating in outdoor recreation. 12.5% were among the homeless population, and 8.75% of heat related hospitalizations were due to a lack of air conditioning. Furthermore, the age group most impacted by heat related illness for this event were between the ages of 20 and 29, accounting for 30% of heat related hospitalizations in the state.
On the 25th, another shortwave trough brought more unsettled weather to the region. A surface front was draped across eastern Nebraska and western Iowa when the first convection initiated over downtown Omaha. This storm quickly became intense producing multiple instances of 3 to 4 inch hail in the Omaha metro. As this storm weakened over eastern Sarpy County, additional strong to severe thunderstorms developed across northeast Nebraska. While the most widespread hazard was large hail up to the size of golf balls, two tornadoes were confirmed in Madison County. Later that evening, a bow echo developed and moved through the northern Omaha Metro, bringing wind gusts up to 90 miles per hour at Eppley Airfield and into northern Pottawattamie County. An additional line of storms developed after dark that night across southeast Nebraska and produced scattered damaging wind gusts, the highest of which was an 83 mph wind gust measured by emergency management in Jefferson County.
The unsettled weather at the end of June brought widespread excessive rain to much of southeast South Dakota and Northwest Iowa. Rainfall estimated from these storms showed a swath of 4 to 8 inches of rain that fell between Sioux Falls and Sioux City. The result of this rain and additional rain across eastern Nebraska and western Iowa was river flooding along the Missouri and Little Sioux the last week of June and into July. Flooding during this time frame resulted in numerous road closures, including I-29 between Council Bluffs and Missouri Valley. This stretch of the interstate was closed beginning midnight the night of the 25th, and remained closed through the end of the month. Levee breaches in Monona County on the 25th prompted several evacuations, as resultant flash flooding inundated multiple county roads and homesteads. No injuries or fatalities were reported from this. While flooding subsided in and north of the Omaha metro by the end of the month, river flooding along the Missouri persisted into the first week of July.