Both radar surfaces caught this storm: NEXRAD logged 15 hail signatures up to 2.75", and the radar-estimated size reached 1.75" aloft. At 2.75" — baseball — this is severe, roof-replacing hail: close to every roof inside the footprint becomes a claim candidate.
A tornado was also reported to the National Weather Service during this storm — see the ground reports below.
2.75"
≈ baseball · the largest NEXRAD radar signature287
2
1 hail · 1 tornadoOverview's storm severity score weighs hailstone size, homes in the footprint, and ground-truth reports.
Largest hailstone — the top predictor of roof damage.
How many homes sit inside the storm's footprint.
Independent storm reports filed with the NWS.
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 — the point detections the storm produced overhead. A signature is where the radar saw hail, not a confirmed stone on the ground.
Maximum hail size as estimated from radar aloft. Treat it as the storm's ceiling — the largest supportable stone — rather than a ground measurement.
This was Amboy's 1st recorded hail day — the first hail day in our records for the city. By severity it ranks 1st of the 6 storms we have logged here. Radar put the day's largest stone over Amboy at 2.75" — the largest NEXRAD radar signature.
The Apr 13, 2026 convective day was bigger than Amboy: the same system put hail over 467 other tracked cities, 71 of them in Minnesota. Nearest: Winnebago (7 miles south, up to 2.75"); Lewisville (7 miles west, up to 2.25"); Garden City (7 miles north, up to 1.75").
These maps are stills from Amboy's Apr 13, 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.
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.
“Updates previous tornado report from 7 WSW Amboy. Multiple reports from storm chasers... fire department... law enforcement. Tornado still on ground at 632 pm. Farm out (MPX)”
— NOAA / SPC storm report
“Report from mPING: Tennis Ball (2.50 in.). (MPX)”
— NOAA / SPC storm report
Hail was reported over 19 minutes, from to .
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.
$3.4M
Potential roof exposure — 287 homes × the ~$12,000 industry-average hail roof claim. Exposure, not confirmed damage.Radar updates in real time, spotter reports appear on the map as they're filed, and the full Amboy storm history — this Apr 13, 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
6 recorded storm days in Amboy, MN
Jul 2, 2026
1"
Jul 1, 2026
Jun 28, 2026
0.75"
Jun 27, 2026
0.5"
May 17, 2026
1.75"