NHC HURDAT2 · SPC Tornado Database
Hurricanes and Tornadoes That Hit Boulder, CO
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, Colorado since records began in 1851. Since 1950, 79 tornadoes have touched down within 25 miles, 1 of them rated EF3 or stronger.
- Hurricanes
- 0
- Tropical storms
- 0
- Tornadoes
- 79
- EF3 or stronger
- 1
within 75 mi, since 1851
below hurricane strength
within 25 mi, since 1950
no recorded deaths
What the records show for Boulder
The strongest of the 79 tornadoes within 25 miles was an EF3 on June 4, 2015; its path came within 17 miles. Of the 79, 4 had paths within 5 miles of the city centre, and 16 have come since 2000. June has had the most tornadoes, 35. The most recent tornado was on June 7, 2021. Boulder has more tornadoes within 25 miles than 51% of the 157 Colorado cities on this site. Hail has been reported within 10 miles 213 times since 1962, with stones up to 3 inches (tea cup size). Boulder has more hail reports within 10 miles than 69% of the 157 Colorado cities.
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Tornadoes within 25 miles of Boulder
By decade
- 2020s1
- 2010s5(1 EF3+)
- 2000s10
- 1990s23
- 1980s22
- 1970s8
- 1960s6
- 1950s4
| Date | Rating | Distance | Path | Killed / injured |
|---|---|---|---|---|
| Jun 4, 2015 | EF3 | 17 mi | 6.71 mi | 0 / 0 |
| Jun 7, 2021 | EF2 | 21 mi | 7.5 mi | 0 / 0 |
| Jun 5, 1988 | F2 | 11 mi | 0.5 mi | 0 / 0 |
| Jun 5, 1988 | F2 | 16 mi | 2 mi | 0 / 0 |
| Jun 3, 1981 | F2 | 18 mi | 2.3 mi | 0 / 42 |
| Jun 3, 1981 | F2 | 24 mi | 0.1 mi | 0 / 0 |
| Oct 15, 1980 | F2 | 2 mi | 1.5 mi | 0 / 0 |
| May 22, 2008 | EF1 | 16 mi | 0.1 mi | 0 / 1 |
| Aug 10, 1999 | F1 | 25 mi | 5 mi | 0 / 0 |
| Jun 22, 1997 | F1 | 21 mi | 0.1 mi | 0 / 0 |
| Jun 15, 1997 | F1 | 17 mi | 0.1 mi | 0 / 0 |
| Jun 6, 1997 | F1 | 3 mi | 0.1 mi | 0 / 0 |
The strongest 12 of 79, by rating and then by deaths. Ratings before February 2007 are on the original Fujita scale.
Hail in Boulder
The Storm Prediction Center has 213 hail reports within 10 miles of Boulder since 1962, made on 100 separate days. Of these, 138 were 1 inch across or larger, and 17 reached 2 inches. The largest, 3 inches (tea cup size), fell on June 18, 2018. The most recent report is from August 10, 2025. June has the most reports, 85.
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, CO, 2 miles south of Boulder at 5,484 feet. July is the warmest, with an average high of 88°F and low of 57°F; December is the coolest, at 46°F and 21°F. May is the wettest at 3.2 inches of precipitation on average and January and December the driest at 0.8 inches; the year adds up to 21.3 inches over 49 days with at least a tenth of an inch. Highs reach 90°F on about 33 days a year, almost all from June to September. Lows fall below freezing on about 138 nights a year. Snowfall averages 92.8 inches a year, most of it in March. That 21.3 inches is more than at 79 of the 91 Colorado stations used on this site (87%). Lafayette, 9 miles east, has its own station (Northglenn, CO): 14.5 inches a year, 6.8 less than here, and a July average high of 91°F against 88°F.
| Month | High °F | Low °F | Precip. in | Days ≥ 0.1" | Snow in |
|---|---|---|---|---|---|
| Jan | 47 | 22 | 0.8 | 3 | 11.3 |
| Feb | 48 | 22 | 1.0 | 4 | 15.0 |
| Mar | 57 | 29 | 2.0 | 4 | 15.7 |
| Apr | 63 | 35 | 3.1 | 6 | 14.7 |
| May | 71 | 43 | 3.2 | 7 | 2.0 |
| Jun | 83 | 51 | 2.0 | 5 | 0.0 |
| Jul | 88 | 57 | 1.8 | 4 | 0.0 |
| Aug | 86 | 56 | 1.7 | 4 | 0.0 |
| Sep | 79 | 48 | 2.1 | 4 | 1.0 |
| Oct | 66 | 37 | 1.6 | 4 | 7.0 |
| Nov | 55 | 28 | 1.2 | 3 | 13.1 |
| Dec | 46 | 21 | 0.8 | 3 | 13.0 |
| Year | 66 | 37 | 21.3 | 49 | 92.8 |
Averages for 1991–2020 at Boulder, CO (5,484 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 51 flood, rain, thunderstorm wind and lightning events that began within 10 miles of Boulder: 26 thunderstorm wind reports, 14 flash floods, 7 lightning strikes, 2 floods and 2 heavy rain events. They killed 1 person and injured 6, and the NWS estimated $297.8 million in property and crop damage. The strongest thunderstorm gust on record here was 75 mph, on July 10, 2011. July has had the most flash floods, 7 of 14. Of the 144 Colorado cities on this site with a flash flood on record, 110 have had fewer than Boulder.
July 14, 2019: lightning strike 5 miles from the centre of Boulder — 1 killed, 1 injured.
NWS: “Two hikers were struck by lightning on Bear Peak off the Bear Peak Trail. The male hiker sustained a direct lightning strike and died later at the hospitail.”
September 12, 2013: flood 9 miles from the centre of Boulder — 3 injured, $297.3 million damage.
June 15, 2009: thunderstorm wind in Boulder — 1 injured, $20,000 damage.
NWS: “Thunderstorm winds knocked a tree on to two vehicles in Boulder. One of the two drivers was injured when the tree smashed the windshield of her car.”
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
Flood insurance policyholders in Boulder's 5 ZIP codes have filed 1,430 claims with the National Flood Insurance Program since 1978, and were paid $31.0 million for buildings and contents, in the dollars of each year. The most came from Late summer storms in 2013: 1,211 claims (85% of all) and $29.9 million. 85% of the claims carry the name of a storm or flood event; the rest have no event name. Of the 56 Colorado cities on this site with 10 or more claims, 55 have fewer than Boulder.
| Event | Claims | Paid |
|---|---|---|
| Late summer storms2013 | 1,211 | $29.9 million |
Boulder County, which includes Boulder, has been named in 19 federal disaster or emergency declarations since 1969, 7 of them major disasters (by incident: 9 fires, 5 floods, 2 biological emergencies, 2 snowstorms). The latest major disaster declaration was Wildfires and Straight-Line Winds, on December 31, 2021. FEMA's National Risk Index gives Boulder County a Relatively Moderate rating for natural hazard risk overall; by hazard: Very High for lightning; Relatively High for tornadoes, hail and strong wind; Relatively Moderate for inland flooding; Relatively Low for heat waves. It models the county's expected loss from all 18 hazards it covers at $125.3 million a year, the 7th highest of 64 Colorado counties; of the hazards above, the largest share, $69.1 million (55%), 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
- Louisville, CO7 mi
- Lafayette, CO9 mi
- Erie, CO13 mi
- Broomfield, CO13 mi
- Nederland, CO14 mi
- Longmont, CO14 mi
- Arvada, CO16 mi
- Westminster, CO16 mi
- Lyons, CO16 mi
- Golden, CO18 mi
- Dacono, CO18 mi
- Frederick, CO18 mi
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