NHC HURDAT2 · SPC Tornado Database
Hurricanes and Tornadoes That Hit Boulder, MT
Every tropical system within 75 miles since 1851 and every tornado within 25 miles since 1950.
Data: NOAA NHC HURDAT2 and NOAA SPC tornado and hail reports, through 2025 · Updated
No tropical storm or hurricane has passed within 75 miles of Boulder, Montana since records began in 1851. Since 1950, 1 tornado has touched down within 25 miles, 0 of them rated EF3 or stronger.
- Hurricanes
- 0
- Tropical storms
- 0
- Tornadoes
- 1
- EF3 or stronger
- 0
within 75 mi, since 1851
below hurricane strength
within 25 mi, since 1950
no recorded deaths
What the records show for Boulder
The only tornado within 25 miles, on August 6, 2023, has no rating; its path came within 6 miles. Of the 73 Montana cities on this site, 89% have more tornadoes within 25 miles than Boulder. Hail has been reported within 10 miles 8 times since 1995, with stones up to 1.5 inches (ping pong ball size). Of the 73 Montana cities, 88% have more hail reports within 10 miles than Boulder.
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Tornadoes within 25 miles of Boulder
By decade
- 2020s1
| Date | Rating | Distance | Path | Killed / injured |
|---|---|---|---|---|
| Aug 6, 2023 | Unrated | 6 mi | 3.66 mi | 0 / 0 |
The strongest 1 of 1, by rating and then by deaths. Ratings before February 2007 are on the original Fujita scale.
Hail in Boulder
The Storm Prediction Center has 8 hail reports within 10 miles of Boulder since 1995, made on 7 separate days. Of these, 6 were 1 inch across or larger, and none reached 2 inches. The largest size, 1.5 inches (ping pong ball size), was reported on 2 days, most recently August 10, 2019. The most recent report is from July 24, 2022.
Source: NOAA Storm Prediction Center severe weather reports, data through 2025.
Weather by month in Boulder
The nearest NOAA station with 1991–2020 climate normals is Boulder, MT, 3 miles northwest of Boulder at 4,904 feet. July is the warmest, with an average high of 83°F and low of 48°F; December is the coolest, at 34°F and 12°F. June is the wettest at 2.3 inches of precipitation on average and February the driest at 0.2 inches; the year adds up to 10.9 inches over 33 days with at least a tenth of an inch. Highs reach 90°F on about 12 days a year, almost all from July to August. Lows fall below freezing on about 205 nights a year. That 10.9 inches is more than at 1 of the 58 Montana stations used on this site (2%). Clancy, 19 miles north, has its own station (Helena Regional Airport, MT): 11.5 inches a year, 0.6 more than here, and a July average high of 86°F against 83°F.
| Month | High °F | Low °F | Precip. in | Days ≥ 0.1" |
|---|---|---|---|---|
| Jan | 35 | 12 | 0.3 | 1 |
| Feb | 38 | 14 | 0.2 | 1 |
| Mar | 47 | 21 | 0.4 | 1 |
| Apr | 55 | 27 | 0.8 | 2 |
| May | 64 | 35 | 1.9 | 5 |
| Jun | 72 | 43 | 2.3 | 6 |
| Jul | 83 | 48 | 1.4 | 5 |
| Aug | 82 | 46 | 1.1 | 4 |
| Sep | 72 | 38 | 1.1 | 3 |
| Oct | 57 | 28 | 0.6 | 2 |
| Nov | 42 | 19 | 0.5 | 2 |
| Dec | 34 | 12 | 0.3 | 1 |
| Year | 57 | 28 | 10.9 | 33 |
Averages for 1991–2020 at Boulder, MT (4,904 ft), from NOAA NCEI U.S. Climate Normals. Normals describe the station; the farther a place is from it, and the bigger the difference in height, the more its weather can differ.
Floods, thunderstorm wind and lightning near Boulder
Since 1996, the National Weather Service has logged 5 flood, rain, thunderstorm wind and lightning events that began within 10 miles of Boulder: 3 thunderstorm wind reports and 2 floods. The strongest thunderstorm gust on record here was 100 mph, on May 10, 2007.
Source: NOAA NCEI Storm Events Database, events whose starting point is on record, 1996 to June 30, 2026. Damage is the NWS estimate in the dollars of the year, not insured losses, and NWS notes that some reports are unverified.
Flood insurance claims, disaster declarations and FEMA risk ratings
Jefferson County, which includes Boulder, has been named in 11 federal disaster or emergency declarations since 1975, 7 of them major disasters (by incident: 3 fires, 3 floods, 2 biological emergencies, 2 severe storms). The latest major disaster declaration was Covid-19 Pandemic, on March 31, 2020. FEMA's National Risk Index gives Jefferson County a Very Low rating for natural hazard risk overall; by hazard: Relatively Moderate for lightning; Very Low for tornadoes, hail, inland flooding, strong wind and heat waves. It models the county's expected loss from all 18 hazards it covers at $8.6 million a year, the 29th highest of 56 Montana counties; of the hazards above, the largest share, $3.9 million (45%), is from inland flooding.
Claims: FEMA, OpenFEMA Dataset FIMA NFIP Redacted Claims – v3, summed over ZIP codes; payments in the dollars of each year, not adjusted for inflation. Declarations: Disaster Declarations Summaries – v2, by county. Retrieved October 25, 2026. This product uses the Federal Emergency Management Agency's OpenFEMA API, but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
Risk ratings: FEMA, National Risk Index county table, December 2025 (v1.20), retrieved October 26, 2026; ratings compare counties nationwide, are meant for planning and are no substitute for a local risk assessment. This product uses the Federal Emergency Management Agency's National Risk Index dataset API or downloadable datasets but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
What counts as a pass, the distances and the sources: how this storm history is built.
Cities near Boulder
- Clancy, MT19 mi
- Whitehall, MT25 mi
- Butte, MT26 mi
- East Helena, MT27 mi
- Helena, MT30 mi
- Townsend, MT32 mi
- Three Forks, MT33 mi
- Deer Lodge, MT34 mi
- Anaconda, MT44 mi
- Manhattan, MT45 mi
- Belgrade, MT49 mi
- Bozeman, MT60 mi
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