Mariposa County

Every recorded tornado

1. Injuries and deaths are for the tornado’s whole path, which may extend beyond the county. Deaths recorded within Mariposa County: 0.
2. Weak tornadoes were under-recorded before Doppler radar coverage became national in the early 1990s, so earlier decades read low. Ratings use the Fujita scale before February 2007 and the Enhanced Fujita scale after.

Storm Prediction Center severe weather database, 1950 to 2025.

Every large fire

1. Large fires mapped by the Monitoring Trends in Burn Severity program since 1984: 1,000 acres or more in the West, 500 or more in the East. Prescribed burns are excluded. Acres here are the part of each perimeter inside this place.

Monitoring Trends in Burn Severity (USGS and U.S. Forest Service), 1984 to 2026.

Smoke overhead

1. A smoke day is a date on which a smoke plume traced by NOAA Hazard Mapping System analysts from satellite imagery covered this place's point (the county's population centre or the city centre). Counts here are of medium or heavy smoke. Since 2018 analysts have often drawn light smoke as one area over most of the continent, so light-smoke counts are not comparable from year to year. The plumes show smoke anywhere in the air above, not air quality at the ground, and smoke hidden by cloud is missed.

NOAA Hazard Mapping System smoke analysis, 2011 to 2026, retrieved October 30, 2026.

OpenFEMA NFIP Redacted Claims v3, refreshed August 4, 2026. NOAA Storm Events through 2026.

River crests

River gauges

1. Crests are the highest and the recent crests the National Weather Service lists for each river gauge in the county that has a flood stage, not every flood. Flood categories use each gauge's current flood stages; crests from before levees, dams or channel changes may not be comparable. Crests measured on an old datum are left out of the rankings.

NOAA National Water Prediction Service gauge records, retrieved October 30, 2026.

1. The Palmer Drought Severity Index is computed by NOAA each month from the county's average temperature and precipitation, relative to the county's own climate. Zero is normal; -3 or lower is severe drought and -4 or lower extreme drought. It describes the long-term balance of moisture, not water supply or crop losses.

NOAA NCEI nClimDiv county Palmer Drought Severity Index, 1895 to September 2026, issued October 6, 2026.

Every earthquake of magnitude 4 or more within 50 miles

1. Earthquakes of magnitude 2.5 or more in the USGS Comprehensive Catalog since 1900. Within 50 miles means the epicentre lies within 50 miles of the county boundary (or inside the county).
2. Small earthquakes were under-recorded before the modern seismic networks of the 1970s and are still missed in remote areas, so early decades read low. Magnitudes are as the catalogue reports them and mix scales (moment, local and body-wave).

USGS ANSS Comprehensive Earthquake Catalog, 1900 to present, retrieved October 30, 2026.

Volcanoes within 100 miles

1. U.S. volcanoes within 100 miles, from the USGS Volcano Hazards Program. The threat category is the USGS 2018 National Volcanic Threat Assessment, which ranks volcanoes by how hazardous their past eruptions were and how many people and how much infrastructure lie near them. It is not a forecast of eruption.

USGS Volcano Hazards Program, retrieved October 30, 2026.

Mapped landslides

Mapped by NASA (20), USGS Seismogenic Mass Movements (16), USGS Conterminous (7).

Deadly landslides

1. Landslides mapped in the USGS compilation of landslide inventories across the United States (version 3.0, 2025), rated probable or better. The compilation joins inventories made by federal and state agencies for different purposes and areas, so the number mapped in a county reflects how closely it has been surveyed as much as how often its slopes fail. An area with few records may simply not have been mapped. Deaths are as recorded in the inventories; a slide listed in two inventories is counted once.

USGS Landslide Inventories across the United States, version 3.0, retrieved October 27, 2026.

More event types since 1996

Costliest events since 1996

1. Jan 9, 2023Winter Storm, Mariposa - Madera Foothills$5.2 million
   National Weather Service narrative

   The Mariposa County Emergency Manager reported that the widespread flooding and damaging winds that took place on January 9th and January 10th resulted in $5.2 million in property damage throughout Mariposa County. Most of this was for road and bridge repairs as well as for the costs of emergency RMO response to clean rock slides, mud slides and debris flows across roads and to pay for overtime and contractors to complete the necessary repairs and cleaning.

2. Jul 24, 2001Wildfire$5.0 million
   National Weather Service narrative

   The Briceburg Fire burned 728 acres and cost $5M to control by August 3rd The cause of the fire is unknown but no structures were lost.

3. Aug 18, 2001Wildfire$3.6 million
   National Weather Service narrative

   The Creek Fire was an arson fire that burned 11,500 acres. There were no fatalities but 11 injuries and 8 structures were lost (4 residences and 4 out-buildings). At one point at least 400 people were forced to evacuate due to the fire and it threatened at least 3000 structures.

4. Oct 1, 2003Wildfire$2.9 million
   National Weather Service narrative

   The Kibbee Complex Fire was allowed to burn for resource management since its ignition on July 20th. It burned a total of 10,100 acres with a final assessed cost of $2.9M. Its location was described as 18 miles NE of Miwok Village in the northwest corner of Yosemite National Park. No fatalities occurred nor were any structures lost.

5. Mar 22, 2018Flash Flood$2.0 million
   National Weather Service narrative

   Mariposa Office of Emergency Services reported several homes flooded and roadways washed out. While many roadways were washed out across Northwestern Mariposa County, the homes were generally impacted near Lake Don Pedro, Hornitos, and the City of Mariposa. The two fatalities that did occur in the area were both related to a person driving into a flooded roadway. One was along highway 132 west of Coulterville and the other was near Cathey's Valley where a 72 year old woman was found dead nearly four months later.

6. Jul 8, 2003Wildfire$1.3 million
   National Weather Service narrative

   The Woodlot Fire inside Yosemite National Park burned 458 acres. The cause is unknown but no structures or fatalities occurred.

7. Jul 3, 2003Wildfire$810,000
   National Weather Service narrative

   The Hunter Fire was fought by the California Division of Forestry and consumed 562 acres. The cause of the fire was unknown but no fatalities occurred nor were any structures lost.

8. Aug 1, 2001Wildfire$778,000
   National Weather Service narrative

   The Hoover Complex Fire started by lightning on July 13, 2001, burned through August, and was still burning toward the end of September. The first spot forecast was received on August 8th and the fire burned about 8040 acres. The fire was shifted as a resource benefit during late August. There were no fatalities, injuries, or structures lost. Cost to contain estimated at $777.8K by 9/21/01.

9. Mar 22, 2018Debris Flow$500,000
   National Weather Service narrative

   California Highway Patrol reported State Route 49 completely closed due to mudslides between State Route 120 and Bear Valley Rd. The road was closed for several days due to erosion from a massive amount of water which washed out the roadway.

10. Jul 28, 2021Thunderstorm Wind$150,000
    National Weather Service narrative

    A tree was blown down in gusty thunderstorm winds and crushed 3 unoccupied tent cabins at Curry Village in Yosemite National Park.

1. Storm Events records before 1996 cover only tornadoes, thunderstorm wind and hail. Damage figures are as reported by the National Weather Service at the time, not adjusted for inflation.

NOAA NCEI Storm Events Database, 1950 to 2026, issued October 26, 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).

OpenFEMA Disaster Declarations Summaries, retrieved October 30, 2026. Statewide declarations are not listed.

Neighbouring counties

• Tornadoes NOAA Storm Prediction Center severe weather database, through 2025.
• Tropical cyclones NOAA National Hurricane Center HURDAT2 (Atlantic; Northeast and Central Pacific), through 2025.
• Wildfire USGS/USFS Monitoring Trends in Burn Severity, through 2026.
• Storm events NOAA NCEI Storm Events Database, through 2026.
• Flood insurance OpenFEMA NFIP Redacted Claims v3, refreshed August 4, 2026.
• Declarations OpenFEMA Disaster Declarations Summaries v2, retrieved October 30, 2026.
• Weather records NOAA NCEI Global Historical Climatology Network Daily.
• River crests NOAA National Weather Service, National Water Prediction Service river gauges, retrieved October 30, 2026.
• Drought NOAA NCEI nClimDiv county Palmer Drought Severity Index, through September 2026.
• Smoke NOAA NESDIS Hazard Mapping System smoke analysis, retrieved October 30, 2026.
• Volcanoes USGS Volcano Hazards Program, U.S. volcanoes and 2018 threat assessment.
• Landslides USGS Landslide Inventories across the United States, version 3.0 (2025).
• Earthquakes USGS ANSS Comprehensive Earthquake Catalog (ComCat), retrieved October 30, 2026.

Joins, thresholds and known limits are set out in the methodology. Found an error? Report it. Page built October 30, 2026.