Wind gust 66 mph
4 E Avon Bon Homme County
“Via personal weather station. Exact time estimated via radar. (FSD)”
— NOAA / SPC storm report
Hail in Avon May 17, 2026
Both radar surfaces caught this storm: NEXRAD logged 10 hail signatures up to 3.25", and the radar-estimated size reached 2" aloft. At 3.25" — baseball — this is severe, roof-replacing hail: close to every roof inside the footprint becomes a claim candidate.
Largest hailstone
3.25"
≈ baseball · the largest NEXRAD radar signature Homes in the hail footprint
460
Ground reports
3
3 windThe most severe storm Avon 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.
7.0 /10
- Hail size
- 81 /100
- Homes exposed
- 53 /100
- Ground truth
- 50 /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 Avon saw the hail — from two instruments
We map this storm two ways: the NEXRAD radar signatures the storm produced overhead, and the radar-estimated size of the hail in the air. The two surfaces don’t have to match — where they diverge is where estimated size aloft ran ahead of, or behind, what the signatures caught.
NEXRAD radar signatures
NEXRAD radar signatures — the point detections the storm produced overhead. A signature is where the radar saw hail, not a confirmed stone on the ground.
Max size
3.25"
Detections
10
Radar-estimated hail size
Maximum hail size as estimated from radar aloft. Treat it as the storm's ceiling — the largest supportable stone — rather than a ground measurement.
Max size
2"
Where May 17, 2026 sits in Avon's hail record
This was Avon's 1st recorded hail day — the first hail day in our records for the city. By severity it ranks 1st of the 3 storms we have logged here. Radar put the day's largest stone over Avon at 3.25" — the largest NEXRAD radar signature.
The May 17, 2026 convective day was bigger than Avon: the same system put hail over 894 other tracked cities, 49 of them in South Dakota. Nearest: Dante (9 miles northwest, up to 3.25"); Tyndall (12 miles northeast, up to 3.5"); Niobrara (13 miles southeast, up to 2.75").
These maps are stills from Avon'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
3 reports Wind gust 79 mph
4 NE Dante Charles Mix County
“Mesonet station 324 SD RWIS WAGNER. (FSD)”
— NOAA / SPC storm report
Wind gust 74 mph
3 E Avon Bon Homme County
“Mesonet station AVMS2 Avon 3E (SD Mesonet). (FSD)”
— NOAA / SPC storm report
Storm forensics
Read from the arrival times and locations of the NOAA ground reports,
not a radar-measured storm track.
How the storm moved
Reports came from Dante — beyond Avon itself.
What 3.25" hail means for Avon roofs
Two-inch-plus hail punctures shingles, breaks skylights and windows, and dents anything soft. In the core of a footprint like this, close to every roof is a candidate for an insurance claim. Speed decides who writes those jobs.
What this storm is worth to a roofer
$5.5M
Potential roof exposure — 460 homes × the ~$12,000 industry-average hail roof claim. Exposure, not confirmed damage.
Illustrative jobs
2 jobs
Illustrative work
~$30K
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 Avon on the live map
Radar updates in real time, spotter reports appear on the map as they're filed, and the full Avon 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
Avon hail history
← All hail in Avon 3 recorded storm days in Avon, SD
Other storms in Avon
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.