Wind gust 60 mph
Winnett Petroleum County
“(GGW)”
— NOAA / SPC storm report
/ Storm field report · Petroleum
Hail in Grass Range · Aug 18, 2026
Hit 25 days ago
NEXRAD logged 0 hail signatures up to 0"; the estimated-size surface reached 2" aloft. At 2" — tennis ball — this is a severe hail signal associated with roof damage. Open it on the live map to see the swath over the streets.
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Peak hail signal 2" ≈ tennis ball · radar-estimated size aloft
Homes in the hail footprint 306
Ground reports 1 1 wind
Radar surfaces 2 NEXRAD + estimated size
Convective day · Aug 18, 2026 · noon–noon UTC
Severity
The most severe storm Grass Range has seen in the last 12 months
Composite score · 4.5 / 10
Storm severity score
Overview's storm severity score weighs hailstone size, homes in the footprint, and ground-truth reports.
4.5 /10
- Peak hail signal
- 50 /100
- Homes exposed
- 50 /100
- Ground truth
- 17 /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 Grass Range saw the hail — from two instruments
Aug 18, 2026 · Grass Range, MT
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 Surface resolved
Radar signature field 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.
Max size
0"
Detections
0
Radar-estimated hail size Surface resolved
Estimated size field Maximum hail size as estimated from radar aloft. Treat it as the storm's ceiling — the largest supportable stone — rather than a ground measurement.
Max size
2"
The storm in context
Where Aug 18, 2026 sits in Grass Range's hail record.
This was Grass Range's 5th recorded hail day, arriving 35 days after the Jul 14, 2026 storm. By severity it ranks 1st of the 7 storms we have logged here. Radar put the day's largest stone over Grass Range at 2" — radar-estimated size aloft.
The Aug 18, 2026 convective day was bigger than Grass Range: the same system put hail over 309 other tracked cities, 6 of them in Montana. Nearest: Winnett (24 miles east, up to 1.25"); Roy (27 miles northwest, up to 0.75"); Roberts (127 miles south, up to 0.5").
These maps are stills. In the app this date is one of 7 Grass Range 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
1 report filed with the NWS
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.
Wind reports
1 reportStorm forensics
How the storm moved
Timing and place names from NOAA ground reports
Read from the arrival times and locations of the NOAA ground reports, not a radar-measured storm track.
Reports came from Winnett — beyond Grass Range itself.
Severe hail signal
What 2" hail means for Grass Range roofs.
Two-inch-plus hail is capable of puncturing shingles, breaking skylights or windows, and heavily denting soft materials. The strongest radar bands warrant prompt inspection, but neither the signal nor the footprint confirms damage at a specific address.
Radar reading · not confirmed damage
Roofing exposure
What this storm is worth to a roofer.
306 homes × $12,000 avg. claim
Potential roof exposure
$3.7M
Potential roof exposure — 306 homes × the ~$12,000 industry-average hail roof claim. Exposure, not confirmed damage.
- Illustrative jobs
- 2 jobs
- Illustrative work
- ~$30K
Close just 0.5% of the 306 homes in this footprint at the average $15,000 roof job. Illustrative math, not a projection — your results depend on your outreach and how the market responds.
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 $64 on top of the $150 plan.
Grass Range hail history
Other storms in Grass Range.
7 recorded storm days in Grass Range, MT
Estimated-size surface Storm date Grass Range / MT
Sep 6, 2026
0.75" Estimated 0.75"
No ground reports filed Open report →
Estimated-size surface Storm date Grass Range / MT
Aug 23, 2026
0.75" Estimated 0.75"
No ground reports filed Open report →
Estimated-size surface Storm date Grass Range / MT
Jul 14, 2026
1.5" Estimated 1.5"
2 ground reports Open report →
Estimated-size surface Storm date Grass Range / MT
Jul 3, 2026
2" Signatures 2" Estimated 1"
1 ground report Open report →
Estimated-size surface Storm date Grass Range / MT
Jul 2, 2026
0.5" Estimated 0.5"
No ground reports filed Open report →
Estimated-size surface Storm date Grass Range / MT
May 29, 2026
2" Signatures 2" Estimated 1.25"
No ground reports filed Open report →
Take your next area into the field.
See the hail, review your recommendations, and canvass with Overview on iPhone.
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For iPhone. Android coming soon.
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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 tells you where to look. Only an inspection confirms damage at an address. Last updated Sep 7, 2026.