Franklin County
Population 70,698 (2025) 699 sq mi
28 tropical storms and hurricanes have passed within 50 miles of Franklin County since 1851, 6 of them at hurricane strength; the strongest was an unnamed storm in 1869 (Category 2).
Hazard fingerprint Each spoke is this county’s percentile among U.S. counties where that hazard occurs. How it is computed
- Tornado damage paths since 195026
- Tropical cyclone tracks within 100 miles since 1851, wider where stronger38
- Major flood years since 19782
At a glance
The record for Franklin County in eight numbers. Each links to its section below.
Tropical cyclones within 50 mi
28
11th of 14 in Massachusetts
6 at hurricane strength since 1851
DetailsTornadoes since 1950
26
2nd of 14 in Massachusetts
86% more than the typical Massachusetts county
DetailsStrongest tornado
F2
July 11, 2006, 2.9 mile path
Strongest tropical cyclone
Cat. 2
Hurricane (unnamed), 1869, 49.7 miles away
Tornadoes
About one every 2.9 years since 1950, none rated F3/EF3 or stronger.
Strongest
July 11, 2006
F2, 2.9 mile path
200 yards wide.
Most recent
Saturday, February 25, 2017
EF1, 4.6 mile path
9 years ago.
Every recorded tornado
| Feb 25, 2017 | EF1 | 4.6 | 1 | 0 |
| Sep 1, 2013 | EF0 | 0.1 | 0 | 0 |
| Jul 11, 2006 | F2 | 2.9 | 0 | 0 |
| Jul 3, 1997 | F1 | 8.5 | 0 | 0 |
| Jul 3, 1997 | F1 | 4.5 | 0 | 0 |
| Jun 27, 1992 | F0 | 0.1 | 4 | 0 |
| Jul 5, 1984 | F1 | 2.0 | 0 | 0 |
| Aug 1, 1983 | F0 | 0.1 | 0 | 0 |
| Aug 2, 1973 | F0 | 3.3 | 0 | 0 |
| Aug 27, 1972 | F2 | 1.0 | 0 | 0 |
| Jul 3, 1972 | F1 | 3.0 | 0 | 0 |
| Jul 3, 1972 | F1 | 1.0 | 0 | 0 |
| Jul 17, 1971 | F1 | 0.5 | 0 | 0 |
| Aug 17, 1970 | F1 | 16.7 | 0 | 0 |
| Jun 18, 1970 | F1 | 18.7 | 0 | 0 |
| Jul 29, 1964 | F1 | 4.3 | 0 | 0 |
| Jul 29, 1964 | F0 | 0.1 | 0 | 0 |
| Sep 12, 1963 | F1 | 1.0 | 0 | 0 |
| May 20, 1963 | F2 | 0.1 | 0 | 0 |
| Jul 2, 1961 | F0 | 2.0 | 0 | 0 |
| Aug 13, 1958 | F1 | 8.0 | 0 | 0 |
| Jul 11, 1958 | F2 | 1.0 | 0 | 0 |
| May 10, 1957 | F1 | 0.2 | 0 | 0 |
| May 10, 1957 | F1 | 0.2 | 0 | 0 |
| Jul 5, 1955 | F2 | 0.1 | 0 | 0 |
| Jul 14, 1954 | F1 | 1.3 | 0 | 0 |
- Injuries and deaths are for the tornado’s whole path, which may extend beyond the county. Deaths recorded within Franklin County: 0.
- 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.
Hurricanes and tropical storms
28 passed within 50 miles since 1851; 6 at hurricane strength.
Strongest within 50 miles
September 8, 1869
Unnamed storm, Category 2
49.7 miles at closest approach, winds near 104 mph.
Most recent
July 9, 2021
Elsa, Tropical storm
66.5 miles at closest approach.
Every storm within 100 miles
| Elsa | 2021 | 66.5 | Tropical storm |
| Isaias | 2020 | 40.8 | Tropical storm |
| Andrea | 2013 | 68.3 | Post-tropical |
| Irene | 2011 | 5.4 | Tropical storm |
| Hanna | 2008 | 43.3 | Post-tropical |
| Barry | 2007 | 65.4 | Post-tropical |
| Floyd | 1999 | 19.1 | Tropical storm |
| Bertha | 1996 | 26.6 | Tropical storm |
| Bob | 1991 | 72.5 | Category 1 |
| Gloria | 1985 | 0.0 | Category 1 |
| David | 1979 | 51.6 | Post-tropical |
| Belle | 1976 | 0.0 | Tropical storm |
| Agnes | 1972 | 79.1 | Post-tropical |
| Doria | 1971 | 0.0 | Tropical storm |
| Unnamed | 1968 | 5.9 | Tropical storm |
| Alma | 1966 | 94.1 | Post-tropical |
| Unnamed | 1961 | 30.5 | Tropical storm |
| Donna | 1960 | 32.8 | Category 1 |
| Brenda | 1960 | 10.9 | Tropical storm |
| Cindy | 1959 | 93.9 | Tropical storm |
| Carol | 1954 | 32.9 | Category 2 |
| Able | 1952 | 0.0 | Tropical storm |
| Unnamed | 1949 | 39.5 | Tropical storm |
| Unnamed | 1944 | 67.9 | Category 1 |
| Unnamed | 1938 | 0.5 | Category 1 |
| Unnamed | 1934 | 11.6 | Post-tropical |
| Unnamed | 1934 | 87.1 | Post-tropical |
| Unnamed | 1929 | 65.6 | Post-tropical |
| Unnamed | 1924 | 4.1 | Post-tropical |
| Unnamed | 1923 | 56.9 | Tropical storm |
| Unnamed | 1916 | 76.3 | Tropical storm |
| Unnamed | 1916 | 36.9 | Post-tropical |
| Unnamed | 1915 | 31.0 | Post-tropical |
| Unnamed | 1908 | 45.7 | Tropical storm |
| Unnamed | 1907 | 88.6 | Post-tropical |
| Unnamed | 1904 | 84.7 | Post-tropical |
| Unnamed | 1902 | 51.4 | Post-tropical |
| Unnamed | 1899 | 7.3 | Post-tropical |
| Unnamed | 1897 | 42.0 | Tropical storm |
| Unnamed | 1896 | 83.1 | Tropical storm |
| Unnamed | 1894 | 31.1 | Tropical storm |
| Unnamed | 1893 | 13.4 | Tropical storm |
| Unnamed | 1893 | 8.7 | Tropical storm |
| Unnamed | 1888 | 51.8 | Post-tropical |
| Unnamed | 1888 | 39.6 | Tropical storm |
| Unnamed | 1882 | 90.6 | Tropical storm |
| Unnamed | 1878 | 6.0 | Post-tropical |
| Unnamed | 1877 | 90.0 | Post-tropical |
| Unnamed | 1874 | 15.1 | Tropical storm |
| Unnamed | 1872 | 56.4 | Tropical storm |
| Unnamed | 1869 | 99.7 | Category 2 |
| Unnamed | 1869 | 49.7 | Category 2 |
| Unnamed | 1866 | 26.5 | Post-tropical |
| Unnamed | 1863 | 46.4 | Tropical storm |
| Unnamed | 1861 | 47.8 | Tropical storm |
| Unnamed | 1861 | 24.6 | Tropical storm |
| Unnamed | 1858 | 37.6 | Category 1 |
| Unnamed | 1851 | 43.3 | Tropical storm |
- 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.
Wildfire and smoke
No large wildfire has been mapped here since satellite mapping began in 1984.
Smoke overhead
Smokiest year
2023: 51 days
Heavy smoke on 8 days in 2023, the most of any year.
Last 10 years
14.5 days a year
Medium or heavy smoke, 2016 to 2025.
2025
16 days
Medium or heavy smoke. 17 so far in 2026.
- 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.
Floods and flood insurance
114 federal flood insurance claims since 1978, with $3.8 million paid.
Most claims in one year
2011: 42 claims
$1.3 million paid.
2nd most
2005: 35 claims
$2.3 million paid.
3rd most
1982: 5 claims
$8,113 paid.
Claims by ZIP code
| 01301 | 48 | $2.8 million |
| 01338 | 9 | $203,000 |
| 01341 | 8 | $179,000 |
| 01339 | 7 | $50,000 |
| 01342 | 7 | $104,000 |
| 5 | $9,139 |
Flood events since 1996
- Flood52
- Flash Flood39
- Heavy Rain10
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
Most severe crest
March 19, 1936
Connecticut River at Montague, 49.20 ft
21.20 feet above the 28.0 ft flood stage; major flooding by today’s categories.
Most recent moderate or major crest
December 18, 2023
Green River at Colrain, 9.10 ft
Moderate flooding.
River gauges
| Connecticut River at Montague | 28.0 | 49.20 ft | 2 |
| Deerfield River at Charlemont | 10.0 | 20.17 ft | 6 |
| Deerfield River at West Deerfield | 9.0 | 23.77 ft | 2 |
| Green River at Colrain | 7.0 | 13.31 ft | 1 |
| Millers River at Erving | 7.0 | 13.37 ft | 1 |
| North River at Shattuckville | 9.0 | 17.66 ft | 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.
Drought
In severe drought or worse for 99 of 1,581 months since 1895 (6%); the longest spell lasted 28 months.
99
Months in severe drought or worse since 1895
28
Months in extreme drought
6%
Share of all months, severe or worse
16
Drought reports to the Weather Service since 1996
Lowest reading
November 1964
−5.44, extreme drought
Longest severe spell
28 months
June 1964 to September 1966.
Latest month
September 2026
−1.98, mild drought
Last severe month: June 2026.
- 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.
Earthquakes and landslides
21 earthquakes of magnitude 2.5 or more within 50 miles since 1907; none reached magnitude 4.
0
Magnitude 2.5+ inside the county since 1973
7
Magnitude 3+ within 50 miles since 1973
0
Magnitude 4+ within 50 miles since 1900
0
Magnitude 5+ within 50 miles since 1900
Largest within 50 miles
October 2, 1994
Magnitude 3.7
6 km W of Hardwick, Massachusetts; 2.0 miles away, 6.2 miles deep.
Most recent, magnitude 3 or more
March 11, 2020
Magnitude 3.1
0 km SSW of South Glens Falls, New York; 49.1 miles away.
- 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).
- 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
1
Landslides mapped, probable or better
1
With a recorded date
1
Source inventory
Mapped by NASA (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.
Severe weather and other events
1,168 events in the National Weather Service record, 1,092 of them since 1996.
45
Hail reports, 1 inch or larger
2
Hail, 2 inches or larger
428
Damaging gusts, 58 mph+
277
Winter weather events since 1996
2
Heat events since 1996
2
Cold events since 1996
Largest hail
May 22, 2013
2.25 inches
Strongest measured or estimated gust
July 11, 2006
90 mph
More event types since 1996
| Lightning | 25 | 0 |
Costliest events since 1996
- Aug 28, 2011Flood$22.0 million
National Weather Service narrative
After receiving eight to ten inches of rain associated with Tropical Storm Irene, major flooding occurred to portions of northwest Massachusetts, from Greenfield northwest through Colrain, Leyden, and vicinity. There were evacuations- exact amount unknown- and there were homes that were condemned. A house on West Leyden Road was reported to have been washed away in Leyden on the Green River. Multiple major routes/highways were affected in western Massachusetts, including Route 2, I-91, Route 20, Route 5, and Route 112 as well as numerous smaller roads. A flood survey along the Deerfield River indicated that in between Routes 5 and I-91, a large swath of farmland was inundated, and…
- Mar 30, 2001Heavy Snow, Western Franklin$8.0 million
National Weather Service narrative
A storm system brought heavy snow to portions of interior Massachusetts, heavy rain and strong winds closer to the coast, and renewed flooding on some rivers and streams in eastern Massachusetts.Snowfall accumulations were confined to the higher terrain of western, central, and northeast Massachusetts where around one foot of snow fell. As much as 15 inches fell in Ashburnham, 12 inches in Leyden and Shelburne, and 11 inches in Shirley. The lower elevations reported snowfall totals between 3 and 6 inches on average. In general, accumulating snows fell along and outside of the Interstate 495 corridor.Strong northeast winds buffeted the coast, averaging between 40 and 50 mph over…
- Aug 28, 2011Tropical Storm, Eastern Franklin$3.0 million
National Weather Service narrative
Trees in Warwick (Sheperdson Road), Gill (Main Road), Shutesbury, and Deerfield (River Road) were downed onto wires. In Shutesbury, a tree was downed onto a house on Shore Drive. A tree on Mill Village Road was downed onto a house in Deerfield.||The Automated Surface Observing Station at Orange Municipal Airport (KORE) recorded sustained wind speeds of 24 knots (28 mph) and gusts to 37 knots (43 mph).
- Mar 9, 2001Heavy Snow, Western Franklin$3.0 million
National Weather Service narrative
A winter storm tracking from the Great Lakes to just south of New England brought heavy snow to much of interior Massachusetts. The highest snowfall totals were found in the higher elevations of central and northeast Massachusetts, where around one foot of snow fell. Other areas, including Greater Boston, received 4 to 8 inches of snow on average.
- Dec 11, 2008Ice Storm, Western Franklin$3.0 million
National Weather Service narrative
Half an inch of ice accumulated on exposed surfaces in western Franklin County. Trees and wires were downed in Ashfield, Buckland, and Shelburne.
- Dec 11, 2008Ice Storm, Eastern Franklin$3.0 million
National Weather Service narrative
Half an inch of ice accumulated on exposed surfaces across eastern Franklin County. Trees, wires, and a utility pole were downed in Greenfield, Sunderland, and Warwick.
- Oct 9, 2005Flood, Eastern Franklin$2.5 million
National Weather Service narrative
A slow-moving cold front interacted with the remnants of Tammy produced significant rain and flooding across western Massachusetts. Northwest Massachusetts, in particular, received between 9 and 11 inches of rain from this event.The significant rainfall washed out numerous roads in Hampshire and Franklin counties, including the towns of Plainfield, Chesterfield, and Bernardston. In Springfield, an apartment roof collapsed due to the weight of water on it. The swollen Green River flooded a mobile home park in Greenfield, knocking some homes off their foundations.No known injuries directly resulted from this heavy rainfall event in Massachusetts.
- Jun 13, 1996Flash Flood$1.8 million
National Weather Service narrative
Thunderstorms with torrential downpours produced a flash flood, which resulted in the worst flooding in 100 years of records on the Sawmill River. All but one access road into the town of Leverett was washed out. The Spaulding Brook experienced its worst flooding in recent memory. A site survey was conducted by the National Weather Service on June 14th. More than 30 miles of roadway in southern Montague and Leverett were destroyed. Numerous homes and businesses experienced some degree of flood damage. The most significant damage was in Leverett along the confluence of the Spaulding Brook and Sawmill Creek, where a two-lane bridge, approximately 200 feet long, was destroyed,…
- Dec 7, 1996Heavy Snow, Eastern Franklin$1.4 million
National Weather Service narrative
A low pressure system centered over Georgia at 7 AM on December 7th moved rapidly northeast across North Carolina. The intensifying system then moved nearly parallel to the Mid-Atlantic coast with its center reaching Plymouth County in southeastern Massachusetts during the early morning hours of December 8th. Temperatures rose into the 50s along and east of the track of the low center...over Plymouth County and Cape Cod. Heavy precipitation occurred across all of Massachusetts with rain over coastal areas and the southeast part of the state and heavy snow in all of western and central Massachusetts and much of Middlesex and Essex counties in the northeastern part of the state. A…
- Dec 7, 1996Heavy Snow, Western Franklin$1.4 million
National Weather Service narrative
A low pressure system centered over Georgia at 7 AM on December 7th moved rapidly northeast across North Carolina. The intensifying system then moved nearly parallel to the Mid-Atlantic coast with its center reaching Plymouth County in southeastern Massachusetts during the early morning hours of December 8th. Temperatures rose into the 50s along and east of the track of the low center...over Plymouth County and Cape Cod. Heavy precipitation occurred across all of Massachusetts with rain over coastal areas and the southeast part of the state and heavy snow in all of western and central Massachusetts and much of Middlesex and Essex counties in the northeastern part of the state. A…
- 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.
Weather records
From Amherst, 13.3 miles from the county’s population centre, with records from 1893.
- All-time high
- 104°FJul 4, 1911
- All-time low
- −30°FJan 22, 1961
- Warmest night
- 80°FJul 5, 1990
- Coldest day
- −3°FDec 30, 1933
- Wettest day
- 7.56 inOct 9, 2005
- Snowiest day
- 18.0 in2 times, most recently Feb 6, 2001
- Hottest year
- 1949mean 52.1°F
- Coldest year
- 1904mean 44.3°F
- Wettest year
- 201863.62 in
- Driest year
- 196327.66 in
- Snowiest season
- 83.9 in1995-96
Median first snow
November 29
Earliest: October 23, 2002
Median last snow
March 28
Latest: May 11, 1945
0 of 88 winters had no measurable snow.
Station Amherst (USC00190120), 145 ft elevation, 13.3 miles from the population centre. Daily records from 1893 to October 27, 2026; 98.4% 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.
Federal disaster declarations
22 since 1953. The most recent: Hurricane Lee, September 15, 2023.
| Sep 15, 2023 | Hurricane | EM-3599-MA |
| Mar 27, 2020 | Biological | DR-4496-MA |
| Mar 13, 2020 | Biological | EM-3438-MA |
| Apr 19, 2013 | Severe Storm | DR-4110-MA |
| Oct 28, 2012 | Hurricane | EM-3350-MA |
| Jan 6, 2012 | Severe Storm | DR-4051-MA |
| Nov 1, 2011 | Severe Storm | EM-3343-MA |
| Sep 3, 2011 | Hurricane | DR-4028-MA |
| Aug 26, 2011 | Hurricane | EM-3330-MA |
| Jan 5, 2009 | Severe Ice Storm | DR-1813-MA |
| Dec 13, 2008 | Severe Storm | EM-3296-MA |
| May 16, 2007 | Severe Storm | DR-1701-MA |
| Nov 10, 2005 | Severe Storm | DR-1614-MA |
| Sep 13, 2005 | Hurricane | EM-3252-MA |
| Feb 17, 2005 | Snowstorm | EM-3201-MA |
| Jan 15, 2004 | Snowstorm | EM-3191-MA |
| Mar 11, 2003 | Snowstorm | EM-3175-MA |
| Mar 28, 2001 | Snowstorm | EM-3165-MA |
| Jan 24, 1996 | Snowstorm | DR-1090-MA |
| Mar 16, 1993 | Snowstorm | EM-3103-MA |
| Apr 18, 1987 | Flood | DR-790-MA |
| Oct 28, 1985 | Hurricane | DR-751-MA |
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.
How this compares
Where Franklin County stands among 14 counties in Massachusetts and 3,143 in the United States.
| Tornadoes since 1950 | 26 | 2 / 14 |
| Tornadoes rated F3/EF3 or stronger | 0 | — |
| Tropical cyclones within 50 mi | 28 | 11 / 14 |
| Hurricane-strength passes within 50 mi | 6 | 10 / 14 |
| Wildfire acres since 1984 | 0 | — |
| Flood insurance claims | 114 | 14 / 14 |
| Flood insurance paid | $3.8 million | 10 / 14 |
| Disaster declarations | 22 | 12 / 14 |
| Flood events since 1996 | 101 | 11 / 14 |
| Hail and wind events since 1996 | 686 | 8 / 14 |
| Winter storm events since 1996 | 277 | 5 / 14 |
| Reported damage since 1996 | $61.1 million | 8 / 14 |
| River crests at major flood stage | 13 | 3 / 14 |
| High tide flooding days a year, last 10 years | 0.0 | — |
| Months in severe drought since 1895 | 99 | 1 / 14 |
| Medium or heavy smoke days a year, last 10 years | 14.5 | 4 / 14 |
| Earthquakes M4+ within 50 mi since 1900 | 0 | — |
| Earthquakes M2.5+ in the county since 1973 | 0 | — |
Neighbouring counties
| Bennington County VT | 6 | 11 |
| Berkshire County | 19 | 19 |
| Cheshire County NH | 18 | 25 |
| Hampshire County | 10 | 29 |
| Windham County VT | 5 | 18 |
| Worcester County | 54 | 32 |
Sources and vintage
Every number on this page comes from these public records.
- 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 USC00190120.
- 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.