San Juan County

Every recorded tornado

1. Injuries and deaths are for the tornado’s whole path, which may extend beyond the county. Deaths recorded within San Juan 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 UT GRC (899), USGS Conterminous (3), NASA (1).

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. Sep 9, 2003Flash Flood$1.0 million
   National Weather Service narrative

   Heavy rainfall resulted in widespread flooding and flash flooding in the area. A law enforcement vehicle en route to rescue stranded residents was caught and washed downstream in a flash flood where the water flowed 5 feet deep. Both vehicle occupants successfully escaped the flood waters, but were stranded for much of the night. 12 houses in Bluff and 6 houses in the community of Montezuma Creek were flooded with water 2 to 3 feet deep. Flash flooding was also reported in the community within the White Mesa Indian Reservation. A sand and gravel company near Bluff was completely inundated with water 20 to 25 feet deep. All of the vehicles and heavy equipment at the company were…

2. Aug 29, 2002Flash Flood$300,000
   National Weather Service narrative

   Heavy rains produced flash flooding which destroyed large sections of three paved county roads and flooded the football field at the Monument Valley High School. Combined destruction of the paved roads was about one mile in length. Road crews moved mud at least a foot deep off of other stretches of the county roads, as well as State Highway 163. Flood waters were flowing at least two feet deep across State Highway 163 near mile marker 11. In some places, the flood waters were up to five feet deep. One person on a Harley Davidson motorcycle plowed into the flood waters which he did not see in time to avoid. The motorcyclist sustained minor injuries. However, the Harley Davidson was…

3. Jun 7, 2006Thunderstorm Wind$175,000
   National Weather Service narrative

   Thunderstorm winds resulted in widespread power outages in Blanding as large trees up to 60 feet tall and tree limbs fell onto power lines. A total of 7 lines were downed and 4 power poles were broken. The majority of the power outages lasted about three and one-half hours. Several homes sustained wind damage, mostly to roofs. Shingles were blown off homes and some metal roofs were blown off or curled up in some places. Trampolines were tossed around yards and neighborhoods, several small sheds were blown over and caused damage to equipment, adjacent homes and vehicles. In one instance a shed was wrapped around a power pole which broke the meter for a nearby trailer. Some portable…

4. Jun 26, 2009Lightning$100,000
   National Weather Service narrative

   Lightning struck an oil battery, heavily damaging two large oil tanks and other equipment.

5. Sep 7, 2002Flash Flood$80,000
   National Weather Service narrative

   Numerous road and trail washouts occurred in the backcountry of Canyonlands National Park. At approximately 1700 MST a family of four was driving a Humvee up Taylor Canyon when water rose to 10 feet deep and carried their vehicle four miles down the wash. The family was able to escape from the vehicle and swim safely to shore. The normally dry wash was running 300 feet wide during the flash flood. The Humvee was totalled.

6. Jun 4, 2025Flash Flood$50,000
   National Weather Service narrative

   Flash flooding was reported along Taylor Canyon on the afternoon of June 4h. This flooding eroded a six food embankment along White Rim Road in Canyonlands National Park, and carried sediment all the way to the Green River. Additionally, several washes along Taylor Canyon Road ran and washed out sections of Taylor Canyon Road. No other damages, and no injuries or fatalities, were received.

7. Jul 25, 2021Debris Flow$50,000
   National Weather Service narrative

   A six foot wall of water, boulders and debris swept over North Desert Solitaire Road within the Pack Creek Fire burn scar.

8. Sep 7, 2002Flash Flood$50,000
   National Weather Service narrative

   Flash flooding washed out most of the temporary road repairs which had been constructed since the 08-29-02 flash flood. A channel 6 to 8 feet deep was gouged out along a section of Highway 63, exposing an apparent gas pipeline.

9. Jul 9, 1996Flash Flood$50,000
   National Weather Service narrative

   Tropical moisture moved into an already unstable airmass over southeast Utah. Thunderstorms developed during the early afternoon in San Juan county and a few had very heavy rainfall. One spotter in Monticello reported receiving 2" of rain in 40 minutes. Another spotter just south of Monticello had 2.64" in 80 minutes. Local officials had extensive reports of basement flooding. Several businesses in town had water damage. State route 191 just south of town had be temporarily closed due to debris on the road.

10. Aug 5, 2013Heavy Rain$40,000
    National Weather Service narrative

    Heavy rainfall of nearly three quarters of an inch was reported in the southwest part of Monticello which led to localized street flooding. Heavier amounts of precipitation fell in other portions of the city which also led to flooding of basements.

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

110°FJun 22, 1905

All-time low

−23°FFeb 8, 1933

Warmest night

79°F2 times, most recently Jul 17, 1925

Coldest day

10°F5 times, most recently Jan 7, 1971

Wettest day

4.48 inAug 1, 1968

Snowiest day

36.0 inDec 23, 1909

Hottest year

2003mean 55.2°F

Coldest year

1916mean 46.2°F

Wettest year

190622.80 in

Driest year

19564.93 in

Snowiest season

117.5 in1978-79

Station Blanding (USC00420738), 6,035 ft elevation, 7.2 miles from the population centre. Daily records from 1904 to July 5, 2026; 94.2% 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 USC00420738.
• 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.