Montana Storm Data: Hail & Wind History Since 2010
Deduplicated storm activity for Montana, fused from NWS warnings, storm reports, official records, and FEMA declarations.
Latest Montana hail and wind storms
- Last reported hail in Montana (0.75 in.+, screening): September 13, 2026 — 1.00 in. reported at 9 W Monarch (Cascade County), SPC storm report.
- 2026 so far in Montana: 27 hail days and 161 wind days statewide (days with a storm report or station gust at the screening thresholds; warnings alone never count).
| Date | Largest reported hail | Strongest gust | City pages hit |
|---|---|---|---|
| October 17, 2026 | — | 77 mph measured | Great Falls |
| October 16, 2026 | — | 68 mph measured | — |
| October 15, 2026 | — | 54 mph measured | — |
| October 10, 2026 | — | 53 mph measured | — |
| October 9, 2026 | — | 55 mph measured | Great Falls |
| October 3, 2026 | — | 46 mph measured | — |
| September 29, 2026 | — | 78 mph measured | Great Falls |
| September 26, 2026 | — | 81 mph measured | Great Falls |
| September 25, 2026 | — | 69 mph measured | Missoula, Great Falls |
| September 15, 2026 | — | 75 mph measured | — |
Cities hit this week
City pages with a storm report or station gust at the screening thresholds (hail 0.75 in.+, wind 45 mph+) within 25 miles in the last 7 days, freshest first.
- Great Falls hail & wind — Oct 17, 2026 · 52 mph gust measured
Montana storm facts
- StormAuditor's analysis of NOAA and National Weather Service records found 6,843 deduplicated storm events (wind, hail, tornado, and flood; NWS warning products included) in Montana in the 12 months ending October 21, 2026.
- Storm activity touched 56 of 56 Montana counties over that period.
- The most impacted county in Montana was Park, with 444 events.
- The busiest day by event count in Montana was December 17, 2025, with 477 events.
Montana storm activity at a glance (last 12 months)
StormAuditor's consolidated public record currently shows 6,843 storm events impacting 56 of Montana's 56 counties in the trailing 12 months: 5,959 wind events, 777 hail events, 107 flood events. Every count includes NWS warnings as well as observed reports, so tornado events mean tornado warnings and reports, not confirmed tornadoes.
Events are fused from National Weather Service warnings and Special Weather Statements, observed Local Storm Reports, official NCEI storm records, and FEMA disaster declarations, then consolidated into a single event table under the published methodology.
Wind covers thunderstorm and non-thunderstorm wind alike, so these counts measure something different from the NCEI entry counts in the history section below; the two are not comparable year to year. State totals also count NWS Special Weather Statements (radar-indicated hail or gusts below warning level); city pages leave those out.
Busiest days in Montana by event count
Ranked by the number of 12-month events, NWS warnings included, so a day with many warnings can outrank a day with larger hail.
- December 17, 2025 — 477 events incl. warnings (wind)
- March 12, 2026 — 325 events incl. warnings (wind)
- March 8, 2026 — 291 events incl. warnings (wind)
- May 13, 2026 — 214 events incl. warnings (hail, wind)
- September 2, 2026 — 158 events incl. warnings (hail, wind)
Most impacted counties
Events of every type for each county — wind, hail, tornado and flood, NWS warnings and Special Weather Statements included. City pages count wind and hail events only, so a county number on a city page is never higher than the number here.
- Park — 444 events
- Glacier — 411 events
- Teton — 270 events
- Sweet Grass — 261 events
- Fergus — 246 events
- Cascade — 226 events
- Liberty — 215 events
- Yellowstone — 207 events
Additional activity recorded under other NWS area names (forecast zones, tribal lands, and former census areas): High Plains (66) · Toole and Liberty (34) · Rocky Mountain Front (32) · Bears Paw Mountains and Southern Blaine (28).
How these numbers are counted
The storm numbers on this page are counted in four different ways, plus the free address check. Each answers a different question with its own size cutoffs, area and time span, so compare numbers within one group, not across groups.
- Storm days (latest hail and wind): A day in the last 12 months when at least one report anywhere in Montana showed hail 0.75 in. or larger or wind of 45 mph or more (StormAuditor screening thresholds). Reports are NWS storm reports from spotters, the public and officials, plus weather-station gusts, which count from 50 mph. A warning on its own never makes a storm day. The "City pages hit" column and each city's last reported hail apply the same rule within 25 miles of the city. The statewide columns count reports inside Montana only. City pages count reports within 25 miles of each city, which can reach into a neighboring state; those values name the other state, so a border city's value for a day can be higher than the Montana value.
- Storm-date pages (NWS severe): A storm-date page is published only when at least one report or station gust within 25 miles of a city met the National Weather Service severe criteria (hail 1.00 in. or larger, or wind 58 mph or more), at least two separate observations were logged, and the day ranks among the most significant. A storm report that relays an airport weather station's reading (the same station, the same gust and the same time) counts once, as the station reading. Not every storm day gets a page; when one does, the page and the storm-day table show the same largest hail and strongest gust.
- Events (12-month counts): Events count the Montana storm log: NWS warnings and Special Weather Statements (a lower-level NWS alert), storm reports (wind 50 mph+, hail 0.75 in.+), station gusts, NCEI entries and FEMA disaster declarations, for each county affected, floods included. One event is one place on one day, counted separately for each type (wind, hail, tornado, flood). A weather station or storm-report point counts once a day, at that day's highest reading, however many readings it filed; a place with hail and wind on the same day is two events. NWS warnings and Special Weather Statements count once per county per day, and NCEI entries and FEMA declarations once per place per day. A storm report that relays an airport weather station's reading (the same station, the same gust and the same time) counts once, as the station reading. The same report arriving through another feed (SPC or NCEI) is one record. The most impacted counties list uses this count. City pages count only wind and hail within 25 miles and leave out floods and Special Weather Statements, so city counts do not add up to the state total, and a city page's county count is a wind-and-hail count that is never higher than the same county's number here.
- NOAA history (since 2010): The official NOAA storm record (NCEI Storm Events) in Montana from January 1, 2010 to the day before the 12-month window starts: hail 0.50 in.+, thunderstorm wind 40 mph+ and tornadoes. It is a separate, older record with its own "storm days" (days with any entry), so its counts are not compared with the 12-month numbers.
- Free Report Snapshot: A free YES/NO estimate for one address, from radar and wind analysis at the property rather than area reports, at the same screening thresholds: hail 0.75 in. or wind 45 mph.
Full method: Methodology and Data Sources.
Montana hail and wind history in NOAA NCEI records, 2010–Oct. 2025
This section covers January 1, 2010 through October 20, 2025. Storms from October 21, 2025 on are in the 12-month summary above, so no date is counted in both.
The National Centers for Environmental Information logged 767 storm days in Montana in this period — 7,923 NCEI Storm Events entries in all. Hail (3,869 reports) and thunderstorm wind (3,968) appear in nearly equal numbers.
Hail and wind both peak in July, the month with 42% of the hail reports. December through February accounts for 2 storm days.
Storm days ranged from 35 in 2015 to 65 in 2013. Across 2022–2024, Montana averaged 45 storm days a year, below the 15-year average of 47.
The largest hail in these records for Montana was 4.25 in. (larger than grapefruit size), reported in 2011, 2013 and 2015 — most recently on June 19, 2015 in Carter County. Hail of 2 inches or more appears in 15 different years of this record, the latest being 2025 through Oct. 20.
Measured thunderstorm gusts topped out at 116 mph (Fergus County, June 10, 2016). NCEI also lists 86 tornado entries in Montana — one entry per county a tornado crossed.
- Average: 47 storm days a year (2010–2024)
- June and July: 74% of all hail reports
- Most hail reports in one year: 466 in 2022
- Hail of 1 in. or larger reported in every full year, 2010–2024
| Year | Hail reports | Thunderstorm wind reports | Tornado entries | Storm days | Largest hail | Strongest measured gust |
|---|---|---|---|---|---|---|
| 2010 | 346 | 161 | 10 | 57 | 4.00 in. | 87 mph |
| 2011 | 273 | 185 | 9 | 49 | 4.25 in. | 85 mph |
| 2012 | 153 | 140 | 2 | 44 | 2.75 in. | 89 mph |
| 2013 | 399 | 321 | 6 | 65 | 4.25 in. | 104 mph |
| 2014 | 236 | 129 | 8 | 48 | 3.50 in. | 81 mph |
| 2015 | 165 | 158 | 3 | 35 | 4.25 in. | 91 mph |
| 2016 | 307 | 205 | 6 | 54 | 4.00 in. | 116 mph |
| 2017 | 66 | 145 | 1 | 41 | 1.75 in. | 115 mph |
| 2018 | 274 | 174 | 10 | 51 | 2.50 in. | 104 mph |
| 2019 | 298 | 230 | 4 | 55 | 3.00 in. | 92 mph |
| 2020 | 172 | 235 | 3 | 37 | 2.50 in. | 89 mph |
| 2021 | 278 | 412 | 2 | 37 | 4.00 in. | 90 mph |
| 2022 | 466 | 600 | 6 | 44 | 3.00 in. | 91 mph |
| 2023 | 150 | 270 | 12 | 45 | 3.00 in. | 91 mph |
| 2024 | 96 | 299 | 4 | 47 | 4.00 in. | 83 mph |
| 2025 through Oct. 20 | 190 | 304 | 0 | 58 | 3.50 in. | 87 mph |
Counties with the most NCEI storm reports, 2010–Oct. 2025
| County | All entries | Hail | Thunderstorm wind |
|---|---|---|---|
| Valley County | 578 | 209 | 359 |
| Yellowstone County | 550 | 309 | 237 |
| Roosevelt County | 316 | 121 | 194 |
| Cascade County | 304 | 144 | 160 |
| Phillips County | 288 | 131 | 154 |
| Garfield County | 273 | 134 | 138 |
| Rosebud County | 273 | 128 | 144 |
| Dawson County | 259 | 110 | 148 |
| Powder River County | 252 | 169 | 79 |
| McCone County | 250 | 116 | 132 |
Download this history: CSV · JSON at https://www.stormauditor.com/downloads/storm-history/mt.json (free, open license, cite StormAuditor).
Source: NOAA NCEI Storm Events Database (thunderstorm wind, hail, and tornado entries; hail 0.50 in. or larger, wind 40 mph or more; wind converted from knots).
Montana storm history questions, 2010–Oct. 2025
What is the largest hail reported in Montana, 2010–Oct. 2025?
4.25 in., larger than grapefruit size, reported in 2011, 2013 and 2015; most recently on June 19, 2015 in Carter County, per NCEI. Hail of 2 inches or more appears in 15 years of this record in all, most recently 2023, 2024 and 2025 through Oct. 20.
What was Montana's most active storm year, 2010–Oct. 2025?
2013, with 65 storm days (399 hail reports, 321 thunderstorm wind reports, 6 tornado entries). The 15-year average is 47 storm days.
How often does Montana get hail?
NCEI's records average 245 hail reports a year here over 2010–2024, alongside 244 thunderstorm wind reports. Hail of 1 inch or larger was reported in every one of those years.
When is hail season in Montana?
July has the most hail reports (1,612, 2010–Oct. 2025), followed by June (1,235) and August (514).
How strong were measured thunderstorm winds in Montana, 2010–Oct. 2025?
116 mph, measured on June 10, 2016 in Fergus County. Only gusts NCEI lists as measured count here; gusts measured on a date and county with a tornado entry, and entries of 120 knots or more (known entry errors), are left out.
Working storm claims? Roofing contractors, public adjusters, and insurance adjusters work from this same public storm record with statewide hail and wind maps and per-address reports — see StormAuditor for professionals.
Sources: NWS alerts (api.weather.gov) · NWS Local Storm Reports via the Iowa Environmental Mesonet · ASOS/AWOS station gusts via the Iowa Environmental Mesonet · NOAA NCEI Storm Events Database · every StormAuditor data source.
Download the Montana dataset (free)
The full consolidated Montana event list for the trailing 12 months — dates, counties, hazard types, severities, measured gusts and hail sizes, with coordinates; source records deduplicated, and each NWS warning product listed per affected county — downloads free and stays current with the live record: download CSV · JSON at https://www.stormauditor.com/downloads/storm-data/mt.json. Free to reuse under the data license; the JSON file carries a field dictionary and provenance notes.
Research a specific Montana address
Statewide counts tell you where activity concentrated; they do not tell you what happened at one property. For an individual address:
- Run the Free Report Snapshot — an instant YES/NO against StormAuditor's screening thresholds (wind ≥ 45 mph, hail ≥ 0.75 in., deliberately below the official NWS severe criteria).
- Use the Address Lookup for warnings, storm reports, and station observations at the address.
- Buy a full Weather Report for $2.99 covering every qualifying storm date at the address.
Browse day-by-day activity on the Storm Calendar (Pro plans and higher) or compare states on the Storm Data hub.
All values are derived from public NOAA and NWS data under StormAuditor's published methodology (see Limitations). Data last refreshed October 21, 2026.
See where recent storms tracked on the statewide Montana hail map and wind map (the Hail and Wind Explorers, included with Pro+ and Organization plans), or check the county impact heatmap (free with an account).
Montana cities A–Z: last reported hail
- Billings hail & wind history — last hail September 7, 2026 (2.75 in. reported)
- Great Falls hail & wind history — no 0.75 in.+ hail reported within 25 miles in 12 months
- Missoula hail & wind history — last hail May 28, 2026 (1.00 in. reported)
Neighboring states: Idaho storm data · North Dakota storm data · South Dakota storm data · Wyoming storm data
Guides for reading this data
Storm-day records in Montana
The newest storm-date pages for Montana cities: a report or station gust within 25 miles of the city met NWS severe criteria (hail 1.00 in.+ or wind 58 mph+), with at least two separate observations. Each page lists the reports, station gusts and a free way to check one address:
Cite or link to this data — free
Free to quote, summarize, reuse, and link — for bloggers, journalists, researchers, contractors, and AI writing tools. No permission or credit required. A ready-made citation and link are below if they help. Terms: StormAuditor data & content license.
Citation: StormAuditor. "Montana Storm Data: Hail & Wind History Since 2010." Updated October 17, 2026. https://www.stormauditor.com/storm-data/mt
HTML link: <a href="https://www.stormauditor.com/storm-data/mt">Montana Storm Data: Hail & Wind History Since 2010 — StormAuditor</a>
About this page: built by Storm Auditor LLC from public NOAA/NWS records — deduplicated warnings, storm reports, station measurements, and official records on a rolling 12-month window, under the published methodology. See the StormAuditor Editorial Team for how content is produced.