Unicoi County

Every recorded tornado

1. Injuries and deaths are for the tornado’s whole path, which may extend beyond the county. Deaths recorded within Unicoi 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 storm within 100 miles

1. Tropical storms and hurricanes (34 kt or more, still tropical) at closest approach. Post-tropical remnants with gale-force winds are listed but not counted. Direct: track within 50 miles; near: within 100 miles. Distance is measured to the county boundary for counties and to the city centre for cities, using positions interpolated hourly between HURDAT2 fixes.

National Hurricane Center HURDAT2, 1851 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.

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.

Mapped landslides

Mapped by 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 27, 2024Flash Flood$9.8 million
   National Weather Service narrative

   Flooding along portions of Hwy 19 was reported at 8:00 am EST. Reports from spotters, social media, broadcast media, and county officials increased through the day, including flooded roadways at 8:51 am EST. Flooding of the Nolichucky River at the Jackson Love Hwy bridge area was noted at 9:32 am EST. Flooding of the grounds around Unicoi Hospital was happening around 10:00 am EST, when a berm was overtopped or breached. The hospital structure was taking water by 11:00 am EST, and evacuation by ground had become unsafe. Occupants were taken to the roof, but winds prevented air rescue while rapidly rising and turbulent river flooding prevented water rescue. The hospital was…

2. Feb 6, 2020Flood$350,000
   National Weather Service narrative

   Numerous roadways were flooded or damaged across the county. Circumstantially, a motorist swerved off of Unicoi Drive around 12:30 AM on the 7th, hit a concrete bridge structure that crosses Buffalo Creek, and rolled over into the flooded creek. The trapped occupant drowned.

3. Aug 17, 2010Flood$70,000
   National Weather Service narrative

   A slow moving thunderstorm produced flooding, including damaging the floor at the local YMCA building in Erwin.

4. Aug 5, 2012Flash Flood$50,000
   National Weather Service narrative

   In and around town of Unicoi. Bedding of the railroad damaged. Serious flooding on Unicoi Drive, Massachusetts Avenue, and Pinnacle Road. Several residents were evacuated from Harris Hollow, Pippin Hollow, and Nelson Hollow Roads.

5. May 21, 2013Flash Flood$40,000
   National Weather Service narrative

   Widespread flash flooding over the northern portion of the county from Erwin northward. Numerous road closures. Water intrusion into a dozen homes and several businesses. Roads undercut. Two evacuations.

6. Oct 17, 2006High Wind, Unicoi$25,000
   National Weather Service narrative

   Several trees and powerlines down countywide.

7. Jul 1, 2005Thunderstorm Wind$25,000
   National Weather Service narrative

   A tent used for fireworks sales just off exit 23 on route 19 was ripped from the ground by thunderstorm gusts. Fireworks were destroyed from the ensuing rainfall.

8. Dec 27, 2011High Wind, Unicoi$25,000
   National Weather Service narrative

   The Erwin newspaper reported utility crews replaced power poles from trees falling on them from the high wind in the Erwin area.

9. Feb 1, 2008High Wind, Unicoi$20,000
   National Weather Service narrative

   The sheriff's office reported several trees down throughout the county. In addition...a portable outhouse was blown across the road and a billboard was destroyed.

10. Jun 13, 1997Thunderstorm Wind$20,000
    National Weather Service narrative

    Trees and powerlines down throughout the county.

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

102°FJul 1, 2012

All-time low

−20°FJan 21, 1985

Warmest night

72°F9 times, most recently Jul 27, 2025

Coldest day

5°FJan 22, 1985

Wettest day

3.68 inMay 7, 1984

Snowiest day

9.0 inJan 28, 1998

Hottest year

1998mean 58.4°F

Coldest year

1981mean 54.1°F

Wettest year

201858.83 in

Driest year

198632.60 in

Snowiest season

36.9 in2010-11

Station Erwin 1 W (USC00402934), 1,720 ft elevation, 1.9 miles from the population centre. Daily records from 1979 to October 5, 2026; 96.9% 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 USC00402934.
• 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.
• 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.