Jefferson County, Colorado
County storm and disaster record · FIPS 08059 · population 582,825 · 764 sq mi
NOAA's Storm Events Database holds 1,455 records for Jefferson County, Colorado from 1950 through June 30, 2026, on 802 days; the most frequent are hail reports (528 records). 773 of them are forecast-zone records, which the National Weather Service files once per zone: a county covered by several zones receives each one, so a single storm can add several records on the same day. The deadliest single record is the March 26, 2012 wildfire, filed for the forecast zone Jefferson & W Douglas Counties Above 6000 Feet / Gilpin / Clear Creek / Ne Park Counties Below 9000 Feet, which covers the county: 3 deaths and $14.1 million in damage in 2025 dollars. FEMA has issued 15 declarations naming the county since 1969, 13 of them for natural hazards; the latest for a natural hazard was “Quarry Fire” on August 1, 2024.
The record, 1950 to 2026
Storm records filed for the county each year (2026 to June 30, 2026). Before 1996 NOAA recorded only tornadoes (from 1950), thunderstorm wind and hail (from 1955).
- recorded, no damage figure
- under $100,000
- $100,000 or more
- $1 million or more
- $10 million or more, or a death
- $100 million or more, or 10 deaths
- a year's colour: its recorded damage or deaths
- a year with a death
- 1955: wind and hail recorded from 1955
- 1996: all 48 event types from 1996
- Storm records
- 1,455on 802 days, 1950 to June 30, 2026
- Deaths recorded
- 21202 injuries
- Damage, 2025 dollars
- $5.9Bas filed (scale steps before 1993)
- Tornadoes
- 13strongest F2
- FEMA declarations
- 15latest 2024
Source: NOAA NCEI Storm Events Database, records through June 30, 2026 (file revision 20260918); damage converted to 2025 dollars with the BLS CPI-U. Search the record at NCEI. BLS consumer price index.
What hazards hit Jefferson County most?
The most frequent records are hail reports: 528 since 1960. 59% of its hail reports since 1960 fell in May and June. The rank column places the county among Colorado's counties by days with a record per 1,000 square miles of land over each hazard's complete period.
| Hazard | Records | Days | First, last | Killed | Injured | Damage | Rank in state |
|---|---|---|---|---|---|---|---|
| Hail | 528 | 196 | 1960-2026 | 0 | 150 | $3.3B | 4 of 63 |
| Winter storms | 466 | 302 | 1996-2026 | 1 | 0 | $50M | 21 of 63 |
| High wind and dust storms | 277 | 198 | 1996-2026 | 3 | 32 | $42M | 4 of 63 |
| Severe thunderstorm wind | 54 | 36 | 1978-2025 | 1 | 0 | – | 19 of 63 |
| Floods | 45 | 37 | 1996-2026 | 3 | 0 | $247M | 3 of 63 |
| Lightning | 34 | 32 | 1996-2023 | 3 | 14 | $2.3M | 2 of 63 |
| Tornadoes | 13 | 11 | 1965-1996 | 0 | 0 | $8.1M | 26 of 63 |
| Wildfires | 12 | 10 | 2000-2025 | 7 | 6 | $2.3B | 23 of 63 |
| Drought | 9 | 5 | 2002-2021 | 0 | 0 | – | 25 of 63 |
| Extreme cold | 8 | 7 | 2011-2025 | 0 | 0 | – | 26 of 63 |
| Landslides and avalanches | 4 | 4 | 2014-2025 | 3 | 0 | – | 31 of 63 |
| Heavy rain | 3 | 2 | 2009-2026 | 0 | 0 | – | 29 of 63 |
| Fog, smoke and funnel clouds | 2 | 1 | 1996-1996 | 0 | 0 | – | 39 of 63 |
Source: NOAA NCEI Storm Events Database (county and forecast-zone records attributed to the county; a zone record shows its own totals on each county it covers). Days: dates with at least one record of the hazard in the county. Ranks: days with a record per 1,000 square miles of land (Census Bureau 2024 Gazetteer), since 1950 for tornadoes, 1955 for hail and thunderstorm wind, 1996 for the rest.
How many tornadoes has Jefferson County had?
NOAA records 13 tornadoes in Jefferson County from 1965 to 1996, the strongest rated F2, with 0 deaths and 0 injuries recorded in the county. That is 26th of 63 Colorado counties by days with tornadoes per 1,000 square miles since 1950. A tornado that crossed a county line is counted in each county it touched, with the length of its path inside the county.
Counted as whole tornadoes rather than county records, the Storm Prediction Center's database holds 13 tornadoes whose track touched Jefferson County since 1950 (NOAA's county records number 13, the same count); along their whole tracks they killed 0 people.
Map of the strongest tornado tracks in Colorado.
Every tornado record filed for Jefferson County (13)
| Date | Place | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 1996-07-28 | Arvada, Jefferson County | F0 0.1 mi x 50 yd | 0 | 0 | – |
| 1995-06-06 | Standley Lake, Jefferson County | F0 0.1 mi x 10 yd | 0 | 0 | – |
| 1990-07-11 | Jefferson County | F0 0.1 mi x 10 yd | 0 | 0 | – |
| 1987-06-20 | Jefferson County | F1 0.2 mi x 20 yd | 0 | 0 | – |
| 1987-06-09 | Jefferson County | F1 0.1 mi x 20 yd | 0 | 0 | – |
| 1982-07-09 | Jefferson County | F1 0.3 mi x 50 yd | 0 | 0 | $30 step |
| 1982-07-09 | Jefferson County | F1 0.3 mi x 50 yd | 0 | 0 | $30 step |
| 1982-06-30 | Jefferson County | F1 0.5 mi x 77 yd | 0 | 0 | $30 step |
| 1981-06-03 | Jefferson County | F2 | 0 | 0 | $2.5M step |
| 1967-07-03 | Jefferson County | F0 | 0 | 0 | – |
| 1965-06-30 | Jefferson County | F0 | 0 | 0 | – |
| 1965-06-30 | Jefferson County | F0 | 0 | 0 | – |
| 1965-06-10 | Jefferson County | F0 | 0 | 0 | – |
A damage figure marked "step" is a record from before 1993: NOAA then filed damage by category, and the figure is the category as entered, in the dollars of that year, not an estimate of the loss.
Source: NOAA NCEI Storm Events Database, tornado records by county (path length in the county, maximum width); ratings as published: F scale before February 1, 2007, EF scale after. Whole-track figures: NOAA Storm Prediction Center tornado database (1950-2025). SPC severe weather database.
When was the last damaging storm in Jefferson County?
The most recent record with damage, injuries or deaths is the June 24, 2026 flash flood ($100,000 in damage in 2025 dollars).
| Date | Record | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 2026-06-26 | HailBroomfield, Jefferson County | 1.00 in hail | 0 | 0 | – |
| 2026-06-24 | Flash FloodEvergreen, Jefferson County | 0 | 0 | $100K | |
| 2026-06-24 | Heavy RainEvergreen, Jefferson County | 0 | 0 | – | |
| 2026-06-24 | Heavy RainEvergreen, Jefferson County | 0 | 0 | – | |
| 2026-06-24 | HailMorrison, Jefferson County | 1.00 in hail | 0 | 0 | – |
| 2026-06-24 | HailMorrison, Jefferson County | 1.00 in hail | 0 | 0 | – |
| 2026-06-24 | HailBergen Park, Jefferson County | 1.00 in hail | 0 | 0 | – |
| 2026-06-08 | HailGolden, Jefferson County | 1.00 in hail | 0 | 0 | – |
| 2026-06-08 | HailKittredge, Jefferson County | 1.75 in hail | 0 | 0 | – |
| 2026-06-08 | HailArvada, Jefferson County | 1.00 in hail | 0 | 0 | – |
| 2026-06-08 | HailGolden, Jefferson County | 1.00 in hail | 0 | 0 | – |
| 2026-06-08 | HailGolden, Jefferson County | 0.75 in hail | 0 | 0 | – |
Source: NOAA NCEI Storm Events Database; every record of 2025-2026 is listed, earlier ones when they caused deaths, injuries or $250,000 of damage (2025 dollars), and every tornado.
The deadliest and costliest records
| Date | Record | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 2012-03-26 | WildfireClear Creek County and 3 more · forecast zone Jefferson & W Douglas Counties Above 6000 Feet / Gilpin / Clear Creek / Ne Park Counties Below 9000 Feet Strong southwest winds ahead of an approaching cold front produced high to extreme fire danger across the Front Range Foothills and Palmer Divide. As a result, a 50-acre prescribed burn that had been conducted the previous week reignited in the foothills of Jefferson County, southwest of Denver. The strong wind gusts ... | 3 | 0 | $14M | |
| 2021-12-30 | WildfireBoulder County and Jefferson County · forecast zone Boulder & Jefferson Counties Below 6000 Feet / W Broomfield County Marshall Fire devastated portions of Marshall, Superior and Louisville. Strong downslope winds, with gusts up to 100 mph, fanned a grass fire that originated near the town of Marshall and quickly spread east to Superior and Louisville. The fire was the costliest fire in state history, and residential and business ... | 2 | 6 | $2.2B | |
| 1996-07-12 | Flash FloodBuffalo Creek, Jefferson County Very heavy rain from a fast moving thunderstorm dumped 2 to 3 inches of rain within an hour over southern Jefferson County. Two people were killed near the town of Buffalo Creek when a 20-ft wall of water blasted through the area. Utility poles and trees were uprooted, cars, propane tanks and bridges were destroyed in ... | 2 | 0 | $978K | |
| 2004-05-29 | LightningLakewood, Jefferson County A father and son practicing on the driving range at the Meadows Golf Club were were struck by lightning. The father was killed by the bolt and his 16-yr old was son seriously injured. Three others standing nearby received only minor injuries. | 1 | 4 | – | |
| 2016-07-19 | LightningArvada, Jefferson County Two men at the Indian Tree Golf Course were struck by lightning when they sought shelter from a rapidly developing thunderstorm under a tree. One man suffered minor injuries, while the other died from this injuries. | 1 | 1 | – | |
| 2025-02-22 | AvalancheBoulder County and 6 more · forecast zone S & Se Grand / W Central & Sw Boulder / Gilpin / Clear Creek / Summit / N & W Park Counties Above 9000 Feet A backcountry skier is dead after being buried in an avalanche on Berthoud Pass Saturday, according to the Colorado Avalanche Information Center. The skier-triggered avalanche happened on Mines Peak east of the pass, in a rocky part of the mountain face known as The Fingers, around 4:45 p.m. | 1 | 0 | – | |
| 2024-08-01 | WildfireBoulder County and 2 more · forecast zone Boulder & Jefferson Counties Below 6000 Feet / W Broomfield County The Stone Canyon Fire started on July 30, 2024 in the Stone Canyon area outside the Town of Lyons. The burned 1,557 acres, destroying five homes and leading to one person’s death. | 1 | 0 | – | |
| 2024-07-30 | WildfireBoulder County and 2 more · forecast zone Boulder & Jefferson Counties Below 6000 Feet / W Broomfield County The Stone Canyon Fire started on July 30, 2024 in the Stone Canyon area outside the Town of Lyons. The burned 1,557 acres, destroying five homes and leading to one person’s death. | 1 | 0 | – |
| Date | Record | Character | Killed | Injured | Damage |
|---|---|---|---|---|---|
| 2017-05-08 | HailEdgewater, Jefferson County | 2.75 in hail | 0 | 0 | $2.8B |
| 2021-12-30 | WildfireBoulder County and Jefferson County · forecast zone Boulder & Jefferson Counties Below 6000 Feet / W Broomfield County | 2 | 6 | $2.2B | |
| 2009-07-20 | HailColumbine, Jefferson County | 1.25 in hail | 0 | 0 | $481M |
| 1997-08-11 | Flash FloodLakewood, Jefferson County | 0 | 0 | $235M | |
| 2020-10-17 | WildfireBoulder County and Jefferson County · forecast zone Boulder & Jefferson Counties Below 6000 Feet / W Broomfield County | 0 | 0 | $42M | |
| 1999-04-09 | High WindClear Creek County and 3 more · forecast zone Southern Front Range Foothills/Clear Creek Basin | 0 | 0 | $24M | |
| 2000-06-12 | WildfirePine, Jefferson County | 0 | 0 | $21M | |
| 2012-03-26 | WildfireClear Creek County and 3 more · forecast zone Jefferson & W Douglas Counties Above 6000 Feet / Gilpin / Clear Creek / Ne Park Counties Below 9000 Feet | 3 | 0 | $14M |
Before 1993 NOAA filed damage by category, not amount, so the list above starts in 1993. The highest category filed here before then (entered as $2.5M, in the dollars of the day) holds: June 3, 1981 (tornado, Jefferson County).
Source: NOAA NCEI Storm Events Database: deaths and injuries direct and indirect; damage is property plus crops as estimated by the National Weather Service, converted to 2025 dollars.
Is it getting more frequent?
Records per decade for Jefferson County's most frequent hazards. Counts rose everywhere after 1996, when NOAA began recording every event type, so compare decades within a hazard's complete period only (the shaded cells come before it).
| Hazard | 1950s | 1960s | 1970s | 1980s | 1990s | 2000s | 2010s | 2020-26 |
|---|---|---|---|---|---|---|---|---|
| Hail | 0 | 8 | 12 | 66 | 82 | 126 | 126 | 108 |
| Winter storms | – | – | – | – | 87 | 98 | 129 | 152 |
| High wind and dust storms | – | – | – | – | 68 | 75 | 55 | 79 |
| Severe thunderstorm wind | 0 | 0 | 1 | 8 | 12 | 13 | 7 | 13 |
| Floods | – | – | – | – | 10 | 18 | 14 | 3 |
| Lightning | – | – | – | – | 9 | 18 | 6 | 1 |
Source: NOAA NCEI Storm Events Database, records per calendar decade; zone records from the CZ_TYPE field (Z).
What time of year?
59% of its hail reports since 1960 fell in May and June. The two busiest months are in violet.
The values, month by month
Jan 113 · Feb 119 · Mar 108 · Apr 122 · May 147 · Jun 277 · Jul 141 · Aug 116 · Sep 44 · Oct 58 · Nov 83 · Dec 127 (records).
Source: NOAA NCEI Storm Events Database, records by the month they began.
Federal disaster declarations for Jefferson County
FEMA's register lists 15 declarations that include Jefferson County: 6 major disasters, 5 emergencies and 4 fire management assistance declarations. Most were for fire (5) and flood (5).
| Declared | Number | Type | Title |
|---|---|---|---|
| 2024-08-01 | FM-5526 | Fire | Quarry Fire |
| 2023-08-25 | DR-4731 | Flood | Severe Storms, Flooding, and Tornadoes |
| 2020-03-28 | DR-4498 | Biological | Covid-19 Pandemic |
| 2020-03-13 | EM-3436 | Biological | Covid-19 |
| 2013-09-14 | DR-4145 | Flood | Severe Storms, Flooding, Landslides, and Mudslides |
| 2013-09-12 | EM-3365 | Flood | Severe Storms, Flooding, Landslides, and Mudslides |
| 2012-03-26 | FM-2975 | Fire | Lower North Fork Fire |
| 2011-03-21 | FM-2873 | Fire | Indian Gulch Fire |
| 2007-01-07 | EM-3270 | Snowstorm | Snow |
| 2005-09-05 | EM-3224 | Coastal Storm | Hurricane Katrina Evacuation |
| 2003-04-09 | EM-3185 | Snowstorm | Snow |
| 2002-06-19 | DR-1421 | Fire | Wildfires |
| 2000-06-12 | FM-2309 | Fire | High Meadows Fire |
| 1973-05-23 | DR-385 | Flood | Heavy Rains, Snowmelt and Flooding |
| 1969-05-19 | DR-261 | Flood | Severe Storms & Flooding |
Source: FEMA OpenFEMA Disaster Declarations Summaries (v2), declarations through October 2, 2026; one declaration is counted once however many areas it names. OpenFEMA dataset page.
How many floods has Jefferson County had?
NOAA's Storm Events Database holds 45 flood or flash flood records for Jefferson County from 1996 to 2026, on 37 days, with 3 deaths. By flood insurance claims since 1978 (OpenFEMA, as of September 8, 2026), Jefferson County ranks 511th of 2,942 U.S. counties.
The National Flood Insurance Program has paid $3.1 million on 491 claims filed in Jefferson County; the most in one year was 63 in 2013. Claims count insured losses only: uninsured flood damage is not in this file.
The values, year by year
1978: 19 · 1979: 19 · 1980: 18 · 1981: 14 · 1982: 11 · 1983: 27 · 1984: 34 · 1985: 2 · 1986: 10 · 1987: 10 · 1988: 3 · 1989: 5 · 1990: 3 · 1991: 13 · 1992: 2 · 1994: 3 · 1995: 17 · 1996: 4 · 1997: 12 · 1998: 21 · 1999: 7 · 2000: 5 · 2001: 5 · 2002: 2 · 2003: 7 · 2004: 7 · 2005: 2 · 2006: 3 · 2007: 11 · 2009: 11 · 2010: 6 · 2011: 6 · 2012: 6 · 2013: 63 · 2014: 8 · 2015: 30 · 2016: 3 · 2017: 4 · 2018: 4 · 2019: 3 · 2020: 2 · 2021: 6 · 2022: 2 · 2023: 21 · 2024: 2 · 2025: 4 · 2026: 14; the other years: 0.
Source: FEMA OpenFEMA NFIP Redacted Claims, as of September 8, 2026; claims by year of loss, payments in the dollars of the year paid. OpenFEMA dataset page.
FEMA's modeled risk for Jefferson County
FEMA's National Risk Index rates Jefferson County Relatively High overall, with an expected annual loss of $231 million. These are FEMA's model estimates of future loss from 18 hazards, not a count of what happened; they can differ from the record above.
| Hazard | Risk rating | Expected annual loss | Modeled frequency |
|---|---|---|---|
| Hail | Very High | $58M | 6.9 a year (modeled) |
| Lightning | Very High | $11M | 58 a year (modeled) |
| Winter Weather | Very High | $1.6M | 19 a year (modeled) |
| Wildfire | Relatively High | $49M | once in about 104 years (modeled) |
| Tornado | Relatively High | $22M | once in about 2 years (modeled) |
| Riverine Flooding | Relatively High | $77M | 1.3 a year (modeled) |
| Strong Wind | Relatively High | $3.3M | about once a year (modeled) |
| Landslide | Relatively Moderate | $559K | once in about 2 years (modeled) |
Source: FEMA National Risk Index, county table, December 2025 release. FEMA's National Risk Index map.
Counties that share a border with Jefferson County
Source: U.S. Census Bureau county adjacency file; NOAA NCEI Storm Events Database, records since 1950. The Census Bureau's adjacency file.
Next
- Tornadoes in ColoradoEvery Colorado tornado since 1950 and the counties with the most per square mile
- Hail in ColoradoThe state's hail reports, by county, year and month
- The Colorado recordEvery hazard in the state, its deadliest events and its federal declarations
- FEMA's risk rating for each hazard in Jefferson CountyThe hazard risk calculator: 18 hazards beside the county's record
- Download Jefferson County's FEMA declarations (CSV)15 rows: every declaration that named the county, for your own analysis