Both radar surfaces caught this storm: NEXRAD logged 9 hail signatures up to 2", and the radar-estimated size reached 1.25" aloft. At 2" — tennis ball — 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"
≈ tennis ball · the largest NEXRAD radar signature814
7
5 hail · 2 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 Sanborn's 1st recorded hail day — the first hail day in our records for the city. By severity it ranks 1st of the 8 storms we have logged here. Radar put the day's largest stone over Sanborn at 2" — the largest NEXRAD radar signature.
The Apr 13, 2026 convective day was bigger than Sanborn: the same system put hail over 467 other tracked cities, 64 of them in Iowa. Nearest: Melvin (7 miles north, up to 2"); Hartley (10 miles southeast, up to 1.25"); Primghar (11 miles south, up to 2.25").
These maps are stills from Sanborn'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.
“Corrects time of previous tornado report from 2 NE Archer. Start of brief tornado which tracked generally north and northwest for around 5 minutes. Track was through op (FSD)”
— NOAA / SPC storm report
“Start of brief tornado which tracked generally north and northwest for around 5 minutes. Track was through open fields with no visible damage. Location and track derive (FSD)”
— NOAA / SPC storm report
“Social media report with picture of estimated hail size. (FSD)”
— NOAA / SPC storm report
“Report from mPING: Quarter (1.00 in.). (FSD)”
— NOAA / SPC storm report
“(FSD)”
— NOAA / SPC storm report
“Report from mPING: Ping Pong Ball (1.50 in.). (FSD)”
— NOAA / SPC storm report
“(FSD)”
— NOAA / SPC storm report
Hail was reported over 74 minutes, from to .
Reports came from Archer — beyond Sanborn itself.
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.
$9.8M
Potential roof exposure — 814 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 Sanborn 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
8 recorded storm days in Sanborn, IA
Jun 30, 2026
1"
Jun 29, 2026
1"
Jun 27, 2026
1.75"
May 31, 2026
May 24, 2026
0.5"
May 18, 2026
2.25"
May 17, 2026
1.75"