Data current as of 2026-10-16 · Sourced from NOAA Storm Events
Over the past five years, the National Oceanic and Atmospheric Administration has recorded 62 hail storms within 25 miles of Mason City, IA. Of those, 53 produced hail at least quarter-size — the threshold most insurance carriers consider potentially damaging to asphalt shingles. The largest reported hail in this window was baseball-sized or larger, which can fracture shingle mat and dent metal flashing on contact. 2026 was the most active year on record locally, with 17 documented hail events.
Check Hail History for a Specific Address in Mason City| Severity | Count | What it means for roofs |
|---|---|---|
| Catastrophic | 1 event | Baseball+ size, structural roof damage likely |
| Destructive | 1 event | Egg-size, expect mat fractures and gutter damage |
| Severe | 14 events | Ping pong-size, granule loss and bruising common |
| Significant | 37 events | Quarter-size, the standard insurance damage threshold |
| Moderate | 9 events | Marble-size, possible cosmetic damage |
| Year | Reported Hail Events Within 25 mi |
|---|---|
| 2026 | 17 events |
| 2025 | 13 events |
| 2024 | 10 events |
| 2023 | 11 events |
| 2022 | 11 events |
2026 was the busiest hail year on record locally for Mason City, with 17 documented events inside the 25-mile radius. Storm activity in Mason City typically peaks in spring and early summer, when the jet stream pushes Gulf moisture into the area and supercell thunderstorms become more frequent.
| Date | Location | Severity | Size | NOAA Comments |
|---|---|---|---|---|
| 2026-08-07 | 2 WNW Thornton, IA | Significant | 1.00" | Report from mPING. Time estimated via radar. |
| 2026-08-07 | Forest City, IA | Significant | 1.00" | From social media. |
| 2026-08-07 | Manly, IA | Severe | 1.50" | Time estimated via radar. |
| 2026-06-11 | 6 SW Marble Rock, IA | Significant | 1.00" | Image via social media. Time estimated from radar. |
| 2026-05-16 | 2 WNW Meservey, IA | Severe | 1.50" | Updated to included windows on house broken. |
| 2026-05-16 | 2 WNW Meservey, IA | Significant | 1.00" | — |
| 2026-05-16 | 4 NW Thornton, IA | Severe | 1.75" | — |
| 2026-05-16 | Garner, IA | Severe | 1.50" | Report from mPING: Ping Pong Ball (1.50 in.). |
| 2026-05-16 | Garner, IA | Significant | 1.00" | — |
| 2026-05-16 | 4 NNW Swaledale, IA | Significant | 1.00" | on I35 near mile marker 186. time estimated from radar. |
| 2026-05-16 | 1 W Ventura, IA | Significant | 1.00" | Report from mPING: Quarter (1.00 in.). |
| 2026-05-16 | 1 WNW Clear Lake, IA | Significant | 1.00" | — |
| 2026-05-16 | Clear Lake, IA | Significant | 1.00" | Report from mPING: Quarter (1.00 in.). |
| 2026-04-14 | 2 W Garner, IA | Severe | 1.50" | — |
| 2026-04-14 | Mason City, IA | Significant | 1.00" | dime to quarter sized hail at time of report. |
| 2026-04-14 | Mason City, IA | Moderate | 0.88" | — |
| 2026-03-06 | 7 W Marble Rock, IA | Severe | 1.63" | Mesonet station 7169D 2 NE Dougherty. |
| 2025-09-22 | GRAFTON, IA | Significant | 1.00" | Delayed report, time estimated by radar. |
| 2025-09-22 | ST ANSGAR ARPT, IA | Significant | 1.00" | The public reported quarter sized hail 2 miles northwest of Saint Ansgar Airport. The reports were relayed from local media. |
| 2025-09-16 | SWALEDALE, IA | Significant | 1.00" | Quarter sized hail reported from the public library. |
NOAA has recorded 70 high-wind events within 25 miles of Mason City, IA in the past five years. Of those, 70 reached severe-thunderstorm thresholds (58+ mph). The highest measured gust was 83 mph.
| Severity | Count |
|---|---|
| Severe | 37 events |
| Significant | 33 events |
| Date | Location | Gust (mph) | Severity | NOAA Comments |
|---|---|---|---|---|
| 2026-09-02 | 1 SSE Forest City, IA | 59 | Significant | Forest City AWOS reported a 51 kt gust at 3:35 AM. |
| 2026-07-20 | 4 S Sheffield, IA | 80 | Severe | Relayed by emergency manager. Time estimated from radar. |
| 2026-07-20 | Nora Springs, IA | 65 | Severe | — |
| 2026-07-02 | 1 S Mason City, IA | 55 | Significant | — |
| 2026-07-02 | 6 SE Mason City, IA | 72 | Severe | PWS gust with a sustained 58mph. |
| 2026-06-28 | 4 W Garner, IA | 58 | Significant | PWS gust. |
| 2026-05-18 | Nora Springs, IA | 70 | Severe | — |
| 2026-05-18 | 4 WNW Mason City, IA | 69 | Severe | — |
| 2026-05-18 | 6 NNW Rockwell, IA | 63 | Significant | — |
| 2026-05-17 | NORA SPGS, IA | 70 | Severe | Local fire and rescue reported a 70 mph wind gust in Nora Springs. |
| 2025-08-15 | AREDALE, IA | 58 | Significant | Tree down on a power line. Time estimated by radar. |
| 2025-07-28 | MILLER, IA | 64 | Severe | Personal Weather Station gust to 64 mph. |
| 2025-07-28 | GARNER, IA | 64 | Severe | Emergency manager relayed trees down in Garner, some roads blocked. |
| 2025-07-28 | VENTURA, IA | 64 | Severe | Emergency manager reported trees down in city of Ventura and power out for part of Clear Lake. |
| 2025-07-28 | VENTURA, IA | 70 | Severe | Large grain bins destroyed in Ventura. Delayed report, time estimated from radar. Relayed via social media. |
| 2025-07-27 | GARNER, IA | 64 | Severe | Multiple large trees and limbs down in town. |
| 2025-07-27 | FOREST CITY, IA | 63 | Significant | Corn stalks blown over and tree limbs down. |
| 2025-07-27 | MASON CITY, IA | 71 | Severe | Trees and Branches down in Mason City. Report of at least one tree on a vehicle. Several power poles on fire. |
| 2025-07-27 | GRAFTON, IA | 64 | Severe | Personal weather station reported gust. |
| 2025-07-27 | ROCK FALLS, IA | 67 | Severe | Large tree limbs down in Plymouth and Rock Falls. Tree on vehicle in Rockfalls. |
The most recent quarter-size-or-larger hail storm recorded by NOAA within 25 miles of Mason City was on August 7, 2026. HailCheck refreshes from the NOAA Storm Events database daily, so newer events appear here as they are reported.
Mason City averages roughly 12 reported hail events per year within a 25-mile radius. Significant storms (quarter-size or larger) account for 53 of the 62 events recorded over the last five years.
The largest documented hail near Mason City in the last five years was baseball-sized or larger. Most Mason City-area hail falls in the marble-to-quarter range, with destructive storms (egg-size or larger) appearing roughly once every few years.
Most homeowners insurance policies in IA cover hail damage to roofs, siding, and gutters under the dwelling and other-structures coverage. Coverage typically requires the damage to be tied to a verifiable storm date — which is where the NOAA hail history above (and a HAAG-style test square validation) becomes important for the claim file.
Use the HailCheck address search to enter any street address in or near Mason City. HailCheck returns every NOAA hail event within a configurable radius, along with severity bands, dates, and storm narratives for Pro members.
If your property in or near Mason City took on hail during one of the storms above, the standard process for documenting damage is a 10×10 foot test square inspection. A HAAG-trained reviewer counts impact indicators — granule displacement, mat fractures, and bruising — within the marked square and produces a PASS or FAIL document for the claim file.
HailCheck offers a $99 photo-based HAAG-style test square validation. You submit photos from the field, our reviewer evaluates the impact indicators and cross-references the NOAA storm dates listed above, and a written PASS/FAIL determination is returned within one business day. We do not send anyone to the roof — the validation is built around the photos you submit.
Learn About $99 HAAG-Style ValidationMason City sits east of the traditional hail alley, where hail events are less frequent than the central plains but tend to be associated with strong squall lines and tropical systems. Local roof systems are less commonly hardened for hail, which can mean even moderate impacts produce claim-worthy damage.