Hail size 1"
Harpers Ferry Allamakee County
“(ARX)”
— NOAA / SPC storm report
Hail in Harpers Ferry Apr 17, 2026
NEXRAD caught this storm: 5 hail signatures up to 1". The radar-estimated size surface had no signal to model this day.
Largest hailstone
1"
≈ quarter · the largest NEXRAD radar signature Homes in the hail footprint
142
Ground reports
1
1 hailThe 2nd most severe storm Harpers Ferry 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.
2.8 /10
- Hail size
- 25 /100
- Homes exposed
- 43 /100
- Ground truth
- 17 /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 Harpers Ferry saw the hail — from two instruments
The maps here read the same storm from two angles — point detections from NEXRAD, and modeled hail size aloft. Where the two disagree is informative: it marks where estimated size outran the signatures, or trailed them.
NEXRAD radar signatures
Where NEXRAD flagged hail as the storm passed — point signatures from the radar, which indicate hail overhead rather than confirm what landed.
Max size
1"
Detections
5
Only the NEXRAD radar-signature surface resolved for Apr 17, 2026 — the estimated-size swath had no hail signal to model for this storm, so there is one map to show, not two.
Where Apr 17, 2026 sits in Harpers Ferry's hail record
This was Harpers Ferry's 2nd recorded hail day, arriving 4 days after the Apr 13, 2026 storm. By severity it ranks 2nd of the 4 storms we have logged here. Radar put the day's largest stone over Harpers Ferry at 1" — the largest NEXRAD radar signature.
The Apr 17, 2026 convective day was bigger than Harpers Ferry: the same system put hail over 1,016 other tracked cities, 201 of them in Iowa. Nearest: Lansing (7 miles north, up to 1"); Waterville (9 miles northwest, up to 0.75"); Eastman (12 miles northeast, up to 1.25").
These maps are stills from Harpers Ferry'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.
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.
Hail reports
1 reportWhat 1" hail means for Harpers Ferry roofs
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.
What this storm is worth to a roofer
$1.7M
Potential roof exposure — 142 homes × the ~$12,000 industry-average hail roof claim. Exposure, not confirmed damage.
Illustrative jobs
1 job
Illustrative work
~$15K
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.
Track hail over Harpers Ferry on the live map
Radar updates in real time, spotter reports appear on the map as they're filed, and the full Harpers Ferry 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
Harpers Ferry hail history
← All hail in Harpers Ferry 4 recorded storm days in Harpers Ferry, IA
Other storms in Harpers Ferry
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 2, 2026.