Hail in Great Falls · Aug 17, 2026
NEXRAD logged 0 hail signatures up to 0"; the estimated-size surface reached 0.75" aloft. Open it on the live map to see the swath over the streets.
7-day free trial in the iPhone app. No card required to start.
For iPhone. Android coming soon.
Web trial: 7 days free. Card required. $150/month after the trial unless cancelled.
Convective day · Aug 17, 2026 · noon–noon UTC
Severity
The 3rd most severe storm Great Falls 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
- 38 /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 Great Falls 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 Aug 17, 2026 sits in Great Falls's hail record.
This was Great Falls's 3rd recorded hail day, arriving 40 days after the Jul 8, 2026 storm. By severity it ranks 3rd of the 4 storms we have logged here. Radar put the day's largest stone over Great Falls at 0.75" — radar-estimated size aloft.
The Aug 17, 2026 convective day was bigger than Great Falls: the same system put hail over 428 other tracked cities, 13 of them in Montana. Nearest: Cascade (25 miles southwest, up to 0.75"); Dutton (34 miles northwest, up to 0.75"); Stanford (52 miles southeast, up to 0.5").
These maps are stills. In the app this date is one of 4 Great Falls 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 Great Falls. 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 Great Falls 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
$888K
Potential roof exposure — 74 homes × the ~$12,000 industry-average hail roof claim. Exposure, not confirmed damage.
Claim window
August 2028
Claims from this storm can typically be filed until around August 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 $16 on top of the $150 plan.
Great Falls hail history
Other storms in Great Falls.
Estimated-size surface Aug 27, 2026
0.5"
NEXRAD surface Jul 8, 2026
1"
Estimated-size surface Jan 23, 2026
0.5"Take your next area into the field.
See the hail, review your recommendations, and canvass with Overview on iPhone.
7-day free trial in the iPhone app. No card required to start.
For iPhone. Android coming soon.
Web trial: 7 days free. Card required. $150/month after the trial unless cancelled.