Wind gust 62 mph
5 NW Thompson Winnebago County
“(DMX)”
— NOAA / SPC storm report
Hail in Thompson May 17, 2026
Both radar surfaces caught this storm: NEXRAD logged 0 hail signatures up to 1", and the radar-estimated size reached 0.5" aloft.
Largest hailstone
1"
≈ quarter · the largest NEXRAD radar signature Homes in the hail footprint
11
Ground reports
1
1 windThe 5th most severe storm Thompson has seen in the last 12 months
Storm severity score
Overview's storm severity score weighs hailstone size, homes in the footprint, and ground-truth reports.
2.3 /10
- Hail size
- 25 /100
- Homes exposed
- 22 /100
- Ground truth
- 17 /100
Largest hailstone — the top predictor of roof damage.
How many homes sit inside the storm's footprint.
Independent storm reports filed with the NWS.
How Thompson saw the hail — from two instruments
Each storm gets two readings: the radar signatures NEXRAD recorded as the cells passed overhead, and a modeled estimate of hail size in the air. They are independent surfaces, so a mismatch between them is expected — and worth reading.
NEXRAD radar signatures
The point detections NEXRAD recorded overhead. Each signature marks where the radar saw hail aloft — it is a detection, not a stone measured on the ground.
Max size
1"
Detections
0
Radar-estimated hail size
Radar-estimated hail size over the swath. The model reports the biggest stone the storm could sustain in the air; what actually fell may have been smaller.
Max size
0.5"
Where May 17, 2026 sits in Thompson's hail record
This was Thompson's 4th recorded hail day, arriving 2 days after the May 15, 2026 storm. By severity it ranks 5th of the 6 storms we have logged here. Radar put the day's largest stone over Thompson at 1" — the largest NEXRAD radar signature.
The May 17, 2026 convective day was bigger than Thompson: the same system put hail over 894 other tracked cities, 139 of them in Iowa. Nearest: Kiester (9 miles northeast, up to 1"); Leland (10 miles east, up to 0"); Emmons (12 miles northeast, up to 1").
These maps are stills from Thompson's May 17, 2026 storm. In the Overview app the same surfaces are live — radar updating in real time, radar-estimated hail size as it forms, and NWS spotter reports pinned where they're filed — with a radar replay you can scrub back over any past day.
What people on the ground reported
These are storm reports filed with the National Weather Service and released through the NOAA Storm Prediction Center — public-domain observations from spotters, the public, and NWS surveys. We quote each one exactly as filed.
Wind reports
1 reportWhat 1" hail means for Thompson roofs
Quarter-size and larger hail is where asphalt shingle damage starts in earnest: bruised mats and granule loss that homeowners can't see from the ground. Most people inside the footprint won't know their roof was hit until someone inspects it.
What this storm is worth to a roofer
$132K
Potential roof exposure — 11 homes × the ~$12,000 industry-average hail roof claim. Exposure, not confirmed damage. Claims from this storm can typically be filed until around May 2028 — the window to reach these homeowners while it's still open. Deadlines vary by policy and state.
Track hail over Thompson on the live map
Radar updates in real time, spotter reports appear on the map as they're filed, and the full Thompson storm history — this May 17, 2026 storm included — sits underneath. When you're ready, draw this storm's footprint and pull highly accurate homeowner contact information for every address inside it.
Highly accurate contact information starting at $0.23 per address — every contact included. Digital leads cost $15–$40. Start with a 7-day free trial — no credit card required. See pricing
Thompson hail history
← All hail in Thompson 6 recorded storm days in Thompson, IA
Other storms in Thompson
Jul 1, 2026
1.75" Signatures 1.75"
No ground reports filed 
Jun 30, 2026
1.75" Signatures 1.75" Estimated 0.75"
No ground reports filed 
May 15, 2026
1" Signatures 1" Estimated 0.5"
No ground reports filed 
Apr 13, 2026
0.5" Estimated 0.5"
No ground reports filed 
Apr 11, 2026
2.5" Signatures 2.5" Estimated 1.5"
1
ground report
A storm day here is a convective day — it runs from noon to noon
UTC, so late-night hail is grouped with the afternoon storm that
spawned it rather than split across two calendar dates. Ground
reports are public-domain observations from the NOAA Storm
Prediction Center. Radar surfaces are detections and estimates,
not confirmed damage. Last updated Aug 3, 2026.