Thunderstorm Wind, Grundy
- When
- July 3, 5:18 PM CST
- Where
- Grundy County, 1.72 mi SW of Grundy Center
- Measured
- 52 kt (60 mph) measured gust
- Reported by
- Public
- Coordinates
- 42.350, -92.790
Damaging Winds in Iowa, July 3, 2025
A deeply unstable air mass was in place across the area with high humidity as dewpoints rose through the upper 70s to near 80 and air temperatures warmed to near 90. This sent heat indices into the low 100s in the afternoon.
Where it happened
Every event with a place to put it. Tap one for its entry below.
- Tornadoes
- Tropical storms and surge
- Floods
- Wind
- Hail
- Winter weather
- Heat and drought
- Cold
- Fire, smoke and dust
- Marine and coastal
- Other
The toll
- Deaths
- 0
- Injuries
- 0
- Property damage
- None recorded
- Crop damage
- None recorded
- Events
- 2
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
What happened
The episode as NWS DMX wrote it up.
A deeply unstable air mass was in place across the area with high humidity as dewpoints rose through the upper 70s to near 80 and air temperatures warmed to near 90. This sent heat indices into the low 100s in the afternoon. While convergence was quite weak across the area, slightly backed winds across eastern Iowa provided enough focus for scattered thunderstorms development in the late afternoon and evening. With a lack of shear across the area, pulse thunderstorms were the primary mode. These storms formed and died quickly, and collapsing updrafts produced gusty winds, including a gust to 60 mph in Grundy county that resulted in tree damage.
The radar
The Des Moines radar (KDMX), 103 km away, was scanning. The volume nearest the first event began at 23:19 UTC.
Event by event
2 thunderstorm wind. Local standard time, as filed.
Thunderstorm Wind, Grundy
- When
- July 3, 5:19 PM CST
- Where
- Grundy County, 0.69 mi S of Grundy Center
- Measured
- 52 kt (60 mph) estimated gust
- Reported by
- Emergency Manager
- Coordinates
- 42.360, -92.770
Six inch tree limbs broken in Grundy Center. Time estimated via radar.
What these are
- Thunderstorm Wind
- Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.
After NWS Directive 10-1605, the rules offices file Storm Data by.
The same day elsewhere
- Damaging Winds in New Jersey, July 3, 2025
- Hail and Damaging Winds in New York, July 3, 2025
- Flash Flooding and Hail in Wisconsin, July 3 to 4, 2025
- Flash Flooding in Texas, July 3, 2025
- Damaging Winds in Pennsylvania, July 3, 2025
- Damaging Winds in Connecticut, July 3, 2025
- Hail and Damaging Winds in North Dakota, July 3 to 4, 2025
- Damaging Winds in Massachusetts, July 3, 2025
- Hail and Damaging Winds in New York, July 3, 2025
- Damaging Winds in New Jersey, July 3, 2025
- Hail and Damaging Winds in Vermont, July 3, 2025
- Hail and Damaging Winds in New York, July 3, 2025
More
Every storm in Iowa in 2025Every state in 2025This day in weather historyWarnings in Iowa, July 2025
Sources
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-10-01. Each event’s entry at NCEI: 1283534, 1283535.