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Natural hazard risk in Jefferson County, Colorado

Updated October 30, 2026. Based on FEMA, NOAA and OpenFEMA data. Published by Humblebee.

FEMA overall Risk Index rating: Relatively High (score 94.9 of 100)[5]

Expected annual loss (FEMA)
$231.4 million[1]
Federal disaster declarations since 1969
13[2]
NFIP flood claims paid, 1978 to 2026
$3.1 million[3]
Tornadoes recorded, 1950 to 2024
13[4]

FEMA rates the overall natural hazard risk for Jefferson County, Colorado as Relatively High compared with other US counties[5]. The hazards with the highest FEMA scores within the county are hail, lightning and wildfire[6].

FEMA risk ratings for each hazard

Ratings and expected losses from the FEMA National Risk Index. Each rating compares this county with all US counties for that hazard, from Very Low to Very High. They are planning estimates, not predictions, and they do not describe any single property.

FEMA's National Risk Index gives Jefferson County a Risk Index score of 94.9 out of 100[5]. FEMA estimates Expected Annual Loss from all 18 natural hazards at $231.4 million a year[1]. By FEMA's estimates, the largest hazard-type losses are inland flooding, hail and wildfire, in that order[7]. Expected Annual Loss is FEMA's estimate of average yearly loss, and it does not predict next year's damage[8]. FEMA rates social vulnerability as Very Low[9] and community resilience as Relatively High[10].

Hazards sorted by FEMA hazard-type Risk Index score, highest first
HazardFEMA risk ratingExpected annual loss
HailVery High$58.0 million[11]
LightningVery High$11.4 million[12]
WildfireRelatively High$48.7 million[13]
Winter WeatherVery High$1.6 million[14]
LandslideRelatively Moderate$559,000[15]
TornadoRelatively High$22.0 million[16]
Inland FloodingRelatively High$77.4 million[17]
Strong WindRelatively High$3.3 million[18]
EarthquakeRelatively Low$3.4 million[19]
AvalancheRelatively Low$131,000[20]
Cold WaveRelatively Moderate$3.3 million[21]
Ice StormRelatively Moderate$325,000[22]
Heat WaveRelatively Low$1.3 million[23]
Volcanic ActivityVery Low$139[24]
DroughtVery Low$24,000[25]

Rated Not Applicable by FEMA for this county: coastal flooding, hurricane, tsunami[26].

Social vulnerability and community resilience

FEMA uses these two ratings to scale expected losses into the Risk Index.

FEMA measureRatingScore
Social vulnerabilityVery Low11.3[9]
Community resilienceRelatively High66.8[10]

Flooding and flood insurance

FEMA rates inland flooding risk Relatively High compared with other US counties[17]. OpenFEMA lists 1,293 residential flood insurance contracts in force, a penetration rate of 0.6%[27]. Inside FEMA's mapped Special Flood Hazard Area, 40.9% of homes are insured[27]. OpenFEMA's NFIP claims show 491 claims filed for losses from 1978 to 2026, and NFIP paid $3.1 million in total[3]. For a specific address, check FEMA's Flood Map Service Center[28].

Measure Value
Inland Flooding, FEMA risk rating[17] Relatively High, $77.4 million expected loss a year
NFIP residential flood policies in force (2026)[27] 1,293 of 205,607 homes
Homes in FEMA's mapped high-risk flood area (SFHA)[27] 1,778, of which 728 insured
NFIP flood claims, 1978 to 2026[3] 491 filed, $3.1 million paid

Is a specific address in a flood zone? Only FEMA's flood maps answer that, property by property[28]. This page describes the whole county.

Search an address on the FEMA Flood Map Service Center

Disaster declarations and tornado records

OpenFEMA lists 13 federal disaster declarations for natural hazards that include Jefferson County since 1969[2]. The most recent is the Quarry Fire, declared 2024-08-01[29]. NOAA's tornado database records 13 tornadoes touching the county from 1950 to 2024, and the strongest were rated F2[4].

Federal disaster declarations for natural hazards that include Jefferson County, since 1969
Incident type Declarations
Fire[2] 5
Flood[2] 5
Snowstorm[2] 2
Coastal Storm[2] 1
Most recent declarations
Declaration Incident Declared
FM-5526-CO[29] Quarry Fire 2024-08-01
DR-4731-CO[29] Severe Storms, Flooding, And Tornadoes 2023-08-25
DR-4145-CO[29] Severe Storms, Flooding, Landslides, And Mudslides 2013-09-14
EM-3365-CO[29] Severe Storms, Flooding, Landslides, And Mudslides 2013-09-12
FM-2975-CO[29] Lower North Fork Fire 2012-03-26

How to prepare

Steps from Ready.gov, FEMA's preparedness site, for the hazards with the highest FEMA ratings here. Follow instructions from local officials and the National Weather Service when a warning is issued.

Wildfires

Before

  • Sign up for community alerts and watch for air quality alerts.
  • Make sure everyone knows the evacuation plan, including for school, work and other places you go often.
  • Keep a fire-resistant zone of at least 30 feet around your home, clear of leaves and debris.
  • Use fire-resistant building materials and keep a hose long enough to reach every part of your property.
  • Pick a room you can seal off from outside air and keep a portable air cleaner ready.

During

  • Leave right away when authorities tell you to evacuate.
  • If you are trapped, call 9-1-1 with your location and turn on lights to help rescuers find you.
  • If you are not ordered to leave but there is smoke, stay in a safe indoor place or go to a community building with less smoke.

Source: Ready.gov, wildfires

Winter storms and cold

Before

  • Insulate your home and learn how to keep pipes from freezing.
  • Install and test smoke and carbon monoxide detectors with battery backup.
  • Keep several days of supplies in case the power goes out, including medication and pet needs.
  • Put an emergency kit in your car with jumper cables, sand, blankets, water and snacks, and keep the tank full.

During

  • Under a winter storm warning, find shelter right away.
  • Stay off the roads if you can. If you are stuck in your car, stay inside it.
  • Run generators and grills only outdoors, away from windows, and never heat your home with an oven or stove.

Source: Ready.gov, winter storms and cold

Tornadoes

Before

  • Learn the warning signs: a rotating funnel cloud, an approaching cloud of debris or a loud roar like a freight train.
  • Sign up for community warning systems and learn what your local sirens sound like.
  • Pick a safe spot, such as a safe room built to FEMA criteria or an ICC 500 storm shelter, and practice getting there.
  • Include your pets in the household emergency plan.
  • Keep supplies, food, water and medication in case you have to stay home for a long time.

During

  • Go right away to the safe place you picked in advance.
  • Protect your head and neck with your arms and stay away from windows, doors and outside walls.
  • No place in a car is fully safe. If you can get lower than the road, leave the car and lie down there.

Source: Ready.gov, tornadoes

Questions people ask

Is Jefferson County, CO at risk of flooding?
FEMA rates inland flooding risk Relatively High compared with other US counties[17]. FEMA estimates its Expected Annual Loss at $77.4 million a year[17].
Is Jefferson County, CO at risk of wildfire?
FEMA rates wildfire risk Relatively High compared with other US counties, with a score of 99.5 out of 100[13]. OpenFEMA lists 5 fire declarations that include the county[2].
Does Jefferson County, CO get tornadoes?
NOAA's tornado database records 13 tornadoes touching the county from 1950 to 2024[4]. FEMA rates tornado risk Relatively High compared with other US counties[16].
Is Jefferson County, CO at risk of hurricanes?
FEMA rates hurricane Not Applicable for the county, because its source data has no historical record of the hazard there[26].
How many federal disasters were declared in Jefferson County, CO?
OpenFEMA lists 13 federal disaster declarations for natural hazards that include the county since 1969[2].

Facts and sources

  1. FEMA National Risk Index (version 1.20, December 2025): Expected Annual Loss from all 18 natural hazards in Jefferson County is $231.4 million a year (Expected Annual Loss rating Relatively High, score 96.5). Of this, buildings account for $195.0 million, injuries and deaths (converted to dollars by FEMA) for $36.3... FEMA National Risk Index
  2. OpenFEMA Disaster Declarations Summaries list 13 federal disaster declarations for natural hazards that include Jefferson County since 1969 (5 major disaster, 8 emergency or fire management). By incident type: fire 5, flood 5, snowstorm 2, coastal storm 1. Biological (such as COVID-19) and other non-natural... OpenFEMA Disaster Declarations
  3. HazardFacts tally of OpenFEMA NFIP Redacted Claims (losses from 1978 to 2026): 491 National Flood Insurance Program claims were filed for losses in Jefferson County, 254 of them with a payment, and NFIP paid $3.1 million in total (building, contents and increased cost of compliance, in dollars of the year paid).... OpenFEMA NFIP claims
  4. NOAA Storm Prediction Center tornado database (1950 to 2024): 13 recorded tornadoes touched Jefferson County. The strongest were rated F2 (most recent of them on 1981-06-03). 0 were rated F3/EF3 or stronger. The most recent recorded tornado was on 1996-07-28. Ratings used the Fujita scale until early 2007 and the... NOAA Storm Prediction Center
  5. FEMA National Risk Index (version 1.20, December 2025): the overall natural hazard Risk Index rating for Jefferson County is Relatively High, with a Risk Index score of 94.9 out of 100. The score is the county's percentile rank among all US counties. FEMA National Risk Index
  6. Among the 18 hazards in the FEMA National Risk Index (version 1.20, December 2025), the hazards with the highest hazard-type Risk Index scores for Jefferson County are hail (99.8, Very High), lightning (99.7, Very High), wildfire (99.5, Relatively High). HazardFacts sorted FEMA's published scores; FEMA's scores... FEMA National Risk Index
  7. HazardFacts sorted FEMA's hazard-type Expected Annual Loss values for Jefferson County (National Risk Index v1.20): the largest are inland flooding ($77.4 million a year), hail ($58.0 million a year), wildfire ($48.7 million a year), out of $231.4 million a year from all 18 hazards. FEMA National Risk Index
  8. FEMA's National Risk Index FAQ (December 2025): Expected Annual Loss is FEMA's estimate of the average economic loss in dollars from natural hazards each year. The index is not meant to predict how much damage a community will have in the next year, and a hazard can still cause damage where a rating is low. Scores... FEMA National Risk Index documentation
  9. FEMA National Risk Index (version 1.20, December 2025): Social Vulnerability rating for Jefferson County is Very Low (score 11.3). FEMA describes social vulnerability as how susceptible social groups are to the harm natural hazards cause. FEMA National Risk Index
  10. FEMA National Risk Index (version 1.20, December 2025): Community Resilience rating for Jefferson County is Relatively High (score 66.8). FEMA describes community resilience as a community's ability to prepare for, withstand and recover from hazards. FEMA National Risk Index
  11. FEMA National Risk Index (version 1.20, December 2025), hail in Jefferson County: Risk Index rating Very High (score 99.8 of 100). Expected Annual Loss $58.0 million a year (rating Very High). Annualized frequency 6.86 events per year, from recorded occurrences over a period of record of 37 years. FEMA National Risk Index
  12. FEMA National Risk Index (version 1.20, December 2025), lightning in Jefferson County: Risk Index rating Very High (score 99.7 of 100). Expected Annual Loss $11.4 million a year (rating Very High). Annualized frequency 57.73 events per year, from recorded occurrences over a period of record of 24 years. FEMA National Risk Index
  13. FEMA National Risk Index (version 1.20, December 2025), wildfire in Jefferson County: Risk Index rating Relatively High (score 99.5 of 100). Expected Annual Loss $48.7 million a year (rating Relatively High). FEMA's modeled annual frequency is 0.0096 events per year. FEMA National Risk Index
  14. FEMA National Risk Index (version 1.20, December 2025), winter weather in Jefferson County: Risk Index rating Very High (score 97.8 of 100). Expected Annual Loss $1.6 million a year (rating Very High). Annualized frequency 18.9 events per year, from recorded occurrences over a period of record of 18 years. FEMA National Risk Index
  15. FEMA National Risk Index (version 1.20, December 2025), landslide in Jefferson County: Risk Index rating Relatively Moderate (score 97.5 of 100). Expected Annual Loss $559,000 a year (rating Relatively Moderate). FEMA National Risk Index
  16. FEMA National Risk Index (version 1.20, December 2025), tornado in Jefferson County: Risk Index rating Relatively High (score 96.5 of 100). Expected Annual Loss $22.0 million a year (rating Relatively High). Annualized frequency 0.56 events per year, from recorded occurrences over a period of record of 38 years. FEMA National Risk Index
  17. FEMA National Risk Index (version 1.20, December 2025), inland flooding in Jefferson County: Risk Index rating Relatively High (score 93.4 of 100). Expected Annual Loss $77.4 million a year (rating Relatively High). Annualized frequency 1.29 event-days per year, from recorded occurrences over a period of record of... FEMA National Risk Index
  18. FEMA National Risk Index (version 1.20, December 2025), strong wind in Jefferson County: Risk Index rating Relatively High (score 92.6 of 100). Expected Annual Loss $3.3 million a year (rating Relatively High). Annualized frequency 0.95 events per year, from recorded occurrences over a period of record of 38 years. FEMA National Risk Index
  19. FEMA National Risk Index (version 1.20, December 2025), earthquake in Jefferson County: Risk Index rating Relatively Low (score 84.0 of 100). Expected Annual Loss $3.4 million a year (rating Relatively Moderate). FEMA's modeled annual frequency is 0.0006 events per year. FEMA National Risk Index
  20. FEMA National Risk Index (version 1.20, December 2025), avalanche in Jefferson County: Risk Index rating Relatively Low (score 77.9 of 100). Expected Annual Loss $131,000 a year (rating Relatively Low). Annualized frequency 0.4 events per year, from recorded occurrences over a period of record of 28 years. FEMA National Risk Index
  21. FEMA National Risk Index (version 1.20, December 2025), cold wave in Jefferson County: Risk Index rating Relatively Moderate (score 73.3 of 100). Expected Annual Loss $3.3 million a year (rating Relatively Moderate). Annualized frequency 0.38 event-days per year, from recorded occurrences over a period of record of... FEMA National Risk Index
  22. FEMA National Risk Index (version 1.20, December 2025), ice storm in Jefferson County: Risk Index rating Relatively Moderate (score 71.8 of 100). Expected Annual Loss $325,000 a year (rating Relatively Moderate). Annualized frequency 0.01 event-days per year, from recorded occurrences over a period of record of 68... FEMA National Risk Index
  23. FEMA National Risk Index (version 1.20, December 2025), heat wave in Jefferson County: Risk Index rating Relatively Low (score 71.0 of 100). Expected Annual Loss $1.3 million a year (rating Relatively Low). Annualized frequency 0.18 event-days per year, from recorded occurrences over a period of record of 18 years. FEMA National Risk Index
  24. FEMA National Risk Index (version 1.20, December 2025), volcanic activity in Jefferson County: Risk Index rating Very Low (score 71.0 of 100). Expected Annual Loss $139 a year (rating Very Low). FEMA National Risk Index
  25. FEMA National Risk Index (version 1.20, December 2025), drought in Jefferson County: Risk Index rating Very Low (score 27.6 of 100). Expected Annual Loss $24,000 a year (rating Very Low). Annualized frequency 22.56 event-days per year, from recorded occurrences over a period of record of 22 years. FEMA National Risk Index
  26. FEMA National Risk Index (version 1.20, December 2025) rates these hazards Not Applicable for Jefferson County: coastal flooding, hurricane, tsunami. FEMA uses Not Applicable when its source data has no historical record of the hazard in the community and the hazard is not considered geographically possible there. FEMA National Risk Index documentation
  27. NFIP Residential Penetration Rates (OpenFEMA, as of 2026-08-03): 1,293 residential flood insurance contracts were in force in Jefferson County, out of 205,607 residential structures, a penetration rate of 0.6%. Inside FEMA's mapped Special Flood Hazard Area there were 1,778 residential structures and 728 contracts,... OpenFEMA NFIP penetration rates
  28. FEMA's Flood Map Service Center is the official public source for flood maps (Flood Insurance Rate Maps) produced under the National Flood Insurance Program. Flood zones apply to specific properties: look up an address there or ask the local floodplain manager. County-level ratings do not tell you the flood zone of... FEMA Flood Map Service Center
  29. Most recent federal disaster declarations for natural hazards (table on this page). OpenFEMA Disaster Declarations

FEMA's National Risk Index compares each county with all other US counties. Ratings are relative (Very Low to Very High), not a measure of safety. Never call a place safe, unsafe, good or bad to live in. Risk Index and Expected Annual Loss values are FEMA estimates for planning. They do not predict next year's losses and do not apply to a single property. Flood zones are set by FEMA flood maps for specific properties. County ratings and flood insurance counts do not tell anyone whether an address is in a flood zone. Disaster declaration, NFIP and tornado counts are records of the past for this county only. Do not compare with other counties unless a fact does.

Federal Emergency Management Agency (FEMA), National Risk Index Dataset: National Risk Index Counties, v1.20 (December 2025). Retrieved from fema.maps.arcgis.com on October 30, 2026. 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). This product uses the FEMA OpenFEMA API, but is not endorsed by FEMA.