Mendocino County

Every recorded tornado

1. Injuries and deaths are for the tornado’s whole path, which may extend beyond the county. Deaths recorded within Mendocino 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.

Claims by ZIP code

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 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.

High tide flooding

1. High tide flooding days are days on which a NOAA tide gauge recorded water at or above NOAA's minor flood threshold, set from the gauge's tide range, counted by meteorological year (May to April). These are the counts in NOAA's annual high tide flooding reports; they are not National Weather Service flood stages. Years with less than 80 percent of data are left out.

NOAA CO-OPS high tide flooding counts, through April 2026, 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.

Tsunamis

1. Places where NOAA's Global Historical Tsunami Database records a tsunami's water arriving, with the greatest height it reached above sea level at the time. Only tsunamis NOAA rates probable or definite are counted. Heights from eyewitness accounts and tide gauges are mixed, and older events are less completely recorded.

NOAA NCEI/WDS Global Historical Tsunami Database, 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 CA GS (33,164), West Coast Slow Moving (Yuankun and others, 2021) (58), NASA (15), USGS Conterminous (9).

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. Dec 29, 2005Flood, Mendocino Interior$42.2 million
   National Weather Service narrative

   A series of strong Pacific storm systems with a subtropical moisture tap began on December 18 and continued through the end of the month. The first 10 days of this wet period conditioned the watersheds with flooding of concern beginning on December 28th. Total precipitation amounts for the series of systems ranged from 12 to 20 inches.While flooding was widespread throughout Humboldt, Del Norte, and Mendocino Counties, the major flood damages occurred in the Klamath River basin and the Russian River Basin. On the Klamath River, two boat ramps were damaged, 15 structures were flooded, and the Klamath River Bridge over HWY 101 sustained 15 million dollars worth of damage. On the…

2. Oct 8, 2017Wildfire, Southeastern Mendocino Interior$38.4 million
   National Weather Service narrative

   Strong downslope winds combined with a hot dry airmass resulted in extreme fire behavior. It is speculated that above normal winter rains yielded abundant fuels that became primed for rapid intense fire spread by late summer and early fall.

3. Sep 12, 2021Wildfire, Southeastern Mendocino Interior$18.0 million
   National Weather Service narrative

   The Hopkins Fire started on September 12th due to arson and was contained on September 20th. A total of 46 structures were destroyed near the community of Calpella, and 5 structures were damaged.

4. Dec 28, 2005Debris Flow, Mendocino Interior$8.7 million
   National Weather Service narrative

   A series of strong Pacific storm systems with a subtropical moisture tap began on December 18 and continued through the end of the month. The first 10 days of this wet period conditioned the watersheds with flooding of concern beginning on December 28th. Total precipitation amounts for the series of systems ranged from 12 to 20 inches.While flooding was widespread throughout Humboldt, Del Norte, and Mendocino Counties, the major flood damages occurred in the Klamath River basin and the Russian River Basin. On the Klamath River, two boat ramps were damaged, 15 structures were flooded, and the Klamath River Bridge over HWY 101 sustained 15 million dollars worth of damage. On the…

5. Jan 9, 2017Heavy Rain$7.0 million
   National Weather Service narrative

   Roadway failure near Laytonville along Highway 101 from milepost 66 to 78.

6. Feb 15, 2017Heavy Rain$6.0 million
   National Weather Service narrative

   Slipout of off ramp from Highway 101 to 271 near Highway 101 mile post 84. Additional landslide covering route 271 between mile post 0 and 4.

7. Jan 17, 2017Heavy Rain$4.5 million
   National Weather Service narrative

   Large landslide and drainage issues near mile post 87 on Highway 101. Slide reported on January 25th and was caused by the heavy rain earlier in the month.

8. Jan 9, 2017Heavy Rain$3.0 million
   National Weather Service narrative

   Multiple areas of bluff erosion and drainage issues along Highway 1 from post mile 78 to 84.

9. Jan 6, 2017Heavy Rain$2.5 million
   National Weather Service narrative

   Two landslides blocking Highway 1 requiring removal and slope stabilization. Highway has been closed for nearly two months.

10. Jan 17, 2017Heavy Rain$2.0 million
    National Weather Service narrative

    Culvert failure and slipouts from mile post 16 to 23 on Highway 162.

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.

All-time high

117°F2 times, most recently Jul 6, 2024

All-time low

18°FDec 9, 2013

Warmest night

71°FAug 3, 2024

Coldest day

39°FDec 6, 2013

Wettest day

4.98 inOct 24, 2021

Hottest year

2024mean 62.5°F

Coldest year

2011mean 58.1°F

Wettest year

201051.91 in

Driest year

20137.50 in

Station Ukiah Municipal Airport (USW00023275), 603 ft elevation, 15.1 miles from the population centre. Daily records from 1949 to October 26, 2026; 85.8% of days in the last 30 years are complete. Records at a single station can differ from a city’s official threaded record, which may combine several stations.

NOAA NCEI Global Historical Climatology Network Daily.

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, station USW00023275.
• River crests NOAA National Weather Service, National Water Prediction Service river gauges, retrieved October 30, 2026.
• Tide gauges NOAA CO-OPS high tide flooding counts, 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.
• Tsunamis NOAA NCEI/WDS Global Historical Tsunami Database.
• 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.