Both radar surfaces caught this storm: NEXRAD logged 13 hail signatures up to 1.25", and the radar-estimated size reached 0.75" aloft.
A tornado was also reported to the National Weather Service during this storm — see the ground reports below.
1.25"
≈ half-dollar · the largest NEXRAD radar signature742
1
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 Alma's 2nd recorded hail day, arriving 4 days after the Apr 13, 2026 storm. By severity it ranks 3rd of the 8 storms we have logged here. Radar put the day's largest stone over Alma at 1.25" — the largest NEXRAD radar signature.
The Apr 17, 2026 convective day was bigger than Alma: the same system put hail over 1,016 other tracked cities, 178 of them in Wisconsin. Nearest: Nelson (8 miles northwest, up to 1.25"); Kellogg (15 miles west, up to 1"); Minnesota City (17 miles south, up to 1.25").
These maps are stills from Alma's Apr 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.
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.
“This EF3 tornado (maximum estimated wind speed 140 mph) formed a few miles southwest of the town of Cream around 3:27 pm and traveled 8 miles to the northeast finally l (ARX)”
— NOAA / SPC storm report
Reports came from Cream — beyond Alma itself.
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.
$8.9M
Potential roof exposure — 742 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 Alma storm history — this Apr 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
8 recorded storm days in Alma, WI
Jul 17, 2026
0.5"
Jun 30, 2026
0.75"
Jun 19, 2026
0.5"
Jun 10, 2026
0.75"
Jun 9, 2026
0.75"
Jun 5, 2026
2"
Apr 13, 2026
2.5"