Heavy Rain — Wayne, Iowa

2021-07-09 to 2021-07-10 · near Allerton, Wayne, Iowa

Event narrative

A 24 hour rain total of 2.29 inches.

Wider weather episode

A shortwave pushed across the area in the overnight to morning hours of July 9th, triggering severe storms over portions of western Iowa in the early morning hours. Storms weakened as they moved east into more stable air, however one cell did develop quarter to golf ball sized hail in Adair county. As the early morning convection continued to weaken and move southeast, additional cells developed in late morning along outflow boundaries left across northern Iowa. By midday a single dominant cell strengthened over central Iowa and dove south southeast. This cell dropped golf ball to baseball sized hail northwest of and across the Des Moines metro through early afternoon. It then dissipated quickly just southeast of the Des Moines metro. The atmosphere recovered through the rest of the afternoon as surface based cape soared to 5000+ J/kg in southwest Iowa paired with 50 knots of 0-6 km shear. Storms developed once more in the late afternoon across eastern Iowa along the outflow boundary put out by the midday supercell. Though the environment was supportive, no storms reached severe thresholds. Overnight yet another round of convection rolled across southern Iowa, producing heavy rain and pushing all lingering convection across eastern Iowa out of the area.

View location on OpenStreetMap → (40.7000, -93.3700)

Source: NOAA Storm Events Database, event_id 971395. Narrative written by the NWS forecast office that issued the report.