Hail in Grundy Center · Apr 17, 2026
NEXRAD logged 3 hail signatures up to 0.75"; the estimated-size surface reached 0" aloft. Open it on the live map to see the swath over the streets.
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Convective day · Apr 17, 2026 · noon–noon UTC
Severity
The 5th most severe storm Grundy Center has seen in the last 12 months
Overview's storm severity score weighs hailstone size, homes in the footprint, and ground-truth reports.
- Peak hail signal
- 19 /100
- Homes exposed
- 40 /100
- Ground truth
- 0 /100
Largest radar-indicated size — a signal of damage potential, not confirmation.
How many homes sit inside the storm's footprint.
Independent storm reports filed with the NWS.
Evidence / storm surfaces
How Grundy Center saw the hail — from two instruments
Two instruments, one storm: NEXRAD logs the point signatures it detected overhead, while the estimated-size surface models how large the hail aloft could have grown. Agreement between them is not guaranteed — the gaps are where the model ran ahead of, or behind, the detections.
Radar signature field NEXRAD's hail signatures for this storm: the spots the radar detected from above. A detection overhead is not the same thing as a confirmed stone below.
Estimated size field Radar-estimated maximum hail size across the swath, modeled from radar aloft. It reflects the biggest stone the storm could support, which may differ from what actually fell.
The storm in context
Where Apr 17, 2026 sits in Grundy Center's hail record.
This was Grundy Center's 3rd recorded hail day, arriving 2 days after the Apr 15, 2026 storm. By severity it ranks 5th of the 7 storms we have logged here. Radar put the day's largest stone over Grundy Center at 0.75" — the largest NEXRAD radar signature.
The Apr 17, 2026 convective day was bigger than Grundy Center: the same system put hail over 1,016 other tracked cities, 201 of them in Iowa. Nearest: Holland (5 miles west, up to 0.75"); Gladbrook (14 miles south, up to 1.25"); Parkersburg (15 miles north, up to 1.5").
These maps are stills. In the app this date is one of 7 Grundy Center storm dates on a live map — both surfaces, the reports, and a replay — and the same map is where you draw the swath. This page rebuilds nightly.
Ground reports
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.
No ground reports were filed with the National Weather Service for this storm over Grundy Center. That is common: a report depends on someone being there to see it and take the time to call it in. The radar surfaces above are the record here — the storm was detected from above even though no one on the ground logged it.
Near the severe threshold
What 0.75" hail means for Grundy Center roofs.
A signal this size sits near the National Weather Service severe threshold. Aging shingles and soft metals such as vents, flashing, and gutters may be more vulnerable; roof age, wind, and material condition all matter, and only an inspection can confirm damage.
Radar reading · not confirmed damage
Roofing exposure
What this storm is worth to a roofer.
Potential roof exposure
$1.1M
Potential roof exposure — 94 homes × the ~$12,000 industry-average hail roof claim. Exposure, not confirmed damage.
Claim window
April 2028
Claims from this storm can typically be filed until around April 2028 — the window to reach these homeowners while it's still open. Deadlines vary by policy and state.
Names and phones for every home in the footprint: at most $20 on top of the $150 plan.
Grundy Center hail history
Other storms in Grundy Center.
Estimated-size surface Aug 10, 2026
0.5"
Estimated-size surface Aug 7, 2026
1"
Estimated-size surface Jul 20, 2026
0.5"
Estimated-size surface Jul 2, 2026
1.25"
Estimated-size surface Apr 15, 2026
0.5"
Estimated-size surface Apr 14, 2026
2.25"The next storm won’t wait for you.
Set your territory and alerts today. When hail hits, use Overview to choose your streets and get moving.
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