The U.S. state of California experiences several tornadoes every year, with at least 488 twisters [nb 1] recorded since 1891. Among these are four fire whirls, a type of tornado that develops from a wildfire. California's strongest rated tornadoes on the Fujita scale (or Enhanced Fujita Scale after 2007) were rated an F/EF3, which occurred three times – two F3 tornadoes in the Greater Los Angeles area in the 1970s, as well as an EF3-equivalent fire whirl near Redding in Shasta County that developed within the 2018 Carr Fire. The fire whirl was one of two deadly tornadic events on record in the state, killing four people. The other deadly event was a tornado that hit Santa Monica in 1952, which killed three people. There have been at least 100 injuries related to tornadoes in the state.
Although less common and not as strong as tornadoes in the central United States, there are regularly tornadoes in three regions of the state – the Los Angeles area, the deserts of Southern California, and the Central Valley. Most tornadoes in California are weak and short-lived, often F0 or EF0, although some can be destructive or notable. Tornadogenesis can occur because of a supercell thunderstorm, a waterspout, a landspout, or a fire whirl, and can happen in any month of the year. The month with the most tornadic activity is March, with most of the state's tornadoes occurring between January and April. Excluding fire whirls, the most recent EF2 tornado was in 2011, which touched down near Oroville in Butte County. In July 2004, a twister touched down in Sequoia National Park at an altitude of around 12,156 ft (3,705 m), making it the highest elevation for a confirmed tornado in the United States. The most California tornadoes on a single day in the state was seven, which occurred on November 9, 1982. More recently, there were five tornadoes on April 1, 1996, as well as October 22, 2012.
In the United States, tornadoes develop less frequently west of the Rocky Mountains as compared to the rest of the continent. In the state of California, three areas more commonly experience tornadoes – in the Los Angeles area, in the deserts of Southern California, and the Central Valley. The Los Angeles area typically experiences more twisters than the rest of the state, and is among the most frequently affected areas in the United States west of the Rockies. [2] California tornadoes are usually weak, categorized as an F0 or F1 on the Fujita scale, or an EF0 or EF1 after the Enhanced Fujita scale was implemented in 2007. Most twisters in the state are also short-lived, with an average path of 0.62 mi (1.00 km) and a width of 43 yd (39 m); this compares with Iowa tornadoes with an average path of 4 mi (6.4 km) and a width of 170 yd (160 m). [3] The vast majority of California tornadoes occur between November and April, accounting for 80.2% of the state's tornadoes according to a 1993 survey. This is during the state's cooler period, which contrasts with the rest of the United States which experiences most of its tornadoes from April to June. [4]
Along the Pacific coast, waterspouts occasionally develop over the ocean and move onshore. In addition, some tornadoes can develop from localized convergence zones known as landspouts, which are often weak and short-lived. Landspouts are the source of the majority of California tornadoes. [5] On rare occasion, tornadoes can originate from supercells, which are more similar in nature to twisters across the Midwestern United States. [6] Because of their irregular and short-lived nature, the San Diego National Weather Service considers it "nearly impossible to forecast a Southern California tornado before it touches down." The agency utilizes a volunteer group of more than 1,300 volunteers to report local severe weather. [5]
In the Los Angeles area, Santa Ana winds can produce a convergence zone when they interact with Lake Elsinore, which can produce a line of thunderstorms capable of spawning a tornado. A similar phenomenon can occur on the north and east side of mountains extending north to Victorville. [5] The location of the mountains relative to the coastline creates the favorable conditions for tornadogenesis in the Los Angeles Area. Due to the area's high population, even weak tornadoes can cause significant impacts. They mostly occur between September and May, not during the summer. Conversely, warm, tropical air can produce tornadoes in the deserts of southern California during the summer. [2] In the Central Valley, tornadoes can form when the winds from a trough are perpendicular to the coastal range of mountains, bringing onshore moisture from the San Francisco area to the Sierra Nevadas. [3] [2] Tornadoes mostly occurred in March and April in the Central Valley. [4]
Due to the large size of California, there is a likely undercount in the number of rural tornadoes. Also, due to the rare nature of tornadoes in the state, it is possible that some reported tornadoes were other weather events, such as a microburst, or straight-line winds. [4]
FU | F0 | F1 | F2 | F3 | F4 | F5 |
---|---|---|---|---|---|---|
12 | 3 | 4 | 6 | 0 | 0 | 0 |
FU | F0 | F1 | F2 | F3 | F4 | F5 |
---|---|---|---|---|---|---|
9 | 3 | 11 | 3 | 0 | 0 | 0 |
FU | F0 | F1 | F2 | F3 | F4 | F5 |
---|---|---|---|---|---|---|
25 | 11 | 6 | 1 | 2 | 0 | 0 |
FU | F0 | F1 | F2 | F3 | F4 | F5 |
---|---|---|---|---|---|---|
1 | 33 | 16 | 9 | 0 | 0 | 0 |
FU | F0 | F1 | F2 | F3 | F4 | F5 |
---|---|---|---|---|---|---|
3 | 76 | 38 | 2 | 0 | 0 | 0 |
FU | F0 | F1 | F2 | F3 | F4 | F5 |
---|---|---|---|---|---|---|
0 | 44 | 9 | 0 | 0 | 0 | 0 |
FU | EF0 | EF1 | EF2 | EF3 | EF4 | EF5 |
---|---|---|---|---|---|---|
0 | 10 | 1 | 1 | 0 | 0 | 0 |
FU | EF0 | EF1 | EF2 | EF3 | EF4 | EF5 | Total | |
---|---|---|---|---|---|---|---|---|
0 | 53 | 16 | 1 | 0 | 0 | 0 | 70 | |
EFU | EF0 | EF1 | EF2 | EF3 | EF4 | EF5 | Total | |
---|---|---|---|---|---|---|---|---|
3 | 23 | 3 | 0 | 0 | 0 | 0 | 24 | |
EFU | EF0 | EF1 | EF2 | EF3 | EF4 | EF5 |
---|---|---|---|---|---|---|
1 | 0 | 3 | 1 | 1 | 0 | 0 |
The following is a chart showing California tornadoes by month or by time period.
Month | Number of tornadoes |
---|---|
January | |
February | |
March | |
April | |
May | |
June | |
July | |
August | |
September | |
October | |
November | |
December |
Period | Number of tornadoes |
---|---|
1800s | |
1900–49 | |
1950s | |
1960s | |
1970s | |
1980s | |
1990s | |
2000s | |
2010s | |
2020s |
The following chart lists the number of tornadoes by county, based on the location of where the twister first touched down, and listed by intensity on the Fujita scale, or the Enhanced Fujita scale after 2007. There have never been any recorded tornadoes in Alpine, Amador, Lake, Modoc, Mono, Napa, Plumas, Sierra, or Trinity counties.
Fire whirls are indicated with a †.
County | EF/FU | EF/F0 | EF/F1 | EF/F2 | EF/F3 | Total |
---|---|---|---|---|---|---|
Alameda | 0 | 2 | 2 | 0 | 0 | 4 |
Butte | 3 | 10 | 6 | 2 | 0 | 21 |
Calaveras | 1 | 0 | 1 | 0 | 0 | 2 |
Colusa | 0 | 4 | 0 | 0 | 0 | 4 |
Contra Costa | 0 | 3 | 0 | 0 | 0 | 3 |
Del Norte | 1 | 3 | 2 | 0 | 0 | 6 |
El Dorado | 0 | 2 | 2 | 0 | 0 | 4 |
Fresno | 1 | 20 | 9† | 1 | 0 | 31 |
Glenn | 0 | 4 | 4 | 1 | 0 | 9 |
Humboldt | 0 | 1 | 0 | 1 | 0 | 2 |
Imperial | 1 | 4 | 2 | 0 | 0 | 7 |
Inyo | 1 | 2 | 0 | 0 | 0 | 3 |
Kern | 0 | 11 | 2 | 0 | 0 | 13 |
Kings | 1 | 5 | 1 | 1 | 0 | 8 |
Lassen | 1† | 1 | 2† | 0 | 0 | 4 |
Los Angeles | 10 | 28 | 11 | 5 | 0 | 54 |
Madera | 2 | 6 | 2 | 1† | 0 | 11 |
Marin | 0 | 0 | 1 | 1 | 0 | 2 |
Mariposa | 0 | 3 | 0 | 0 | 0 | 3 |
Mendocino | 2 | 1 | 1 | 0 | 0 | 4 |
Merced | 1 | 13 | 5 | 0 | 0 | 19 |
Monterey | 0 | 3 | 2 | 0 | 0 | 5 |
Nevada | 0 | 0 | 1 | 0 | 0 | 1 |
Orange | 5 | 13 | 10 | 1 | 1 | 30 |
Placer | 0 | 5 | 2 | 0 | 0 | 7 |
Riverside | 3 | 18 | 4 | 1 | 1 | 27 |
Sacramento | 0 | 10 | 2 | 3 | 0 | 15 |
San Benito | 0 | 1 | 0 | 1 | 0 | 2 |
San Bernardino | 8 | 17 | 5 | 2 | 0 | 32 |
San Diego | 11 | 17 | 8 | 1 | 0 | 37 |
San Francisco | 1 | 0 | 0 | 0 | 0 | 1 |
San Joaquin | 3 | 13 | 2 | 0 | 0 | 18 |
San Luis Obispo | 0 | 2 | 2 | 0 | 0 | 4 |
San Mateo | 1 | 1 | 1 | 0 | 0 | 3 |
Santa Barbara | 3† | 6 | 0 | 0 | 0 | 9 |
Santa Clara | 0 | 3 | 1 | 2 | 0 | 6 |
Santa Cruz | 0 | 5 | 2 | 0 | 0 | 7 |
Shasta | 0 | 0 | 0 | 0 | 1† | 1 |
Siskiyou | 0 | 0 | 1 | 0 | 0 | 1 |
Solano | 0 | 4 | 0 | 0 | 0 | 4 |
Sonoma | 2 | 1 | 7 | 0 | 0 | 10 |
Stanislaus | 1 | 3 | 3 | 1 | 0 | 8 |
Sutter | 0 | 4 | 1 | 0 | 0 | 5 |
Tehama | 3 | 6 | 0 | 2 | 0 | 11 |
Tulare | 1 | 12 | 1 | 0 | 0 | 14 |
Tuolumne | 0 | 1 | 0 | 0 | 0 | 1 |
Ventura | 0 | 6 | 0 | 0 | 0 | 6 |
Yolo | 0 | 6 | 0 | 0 | 0 | 6 |
Yuba | 0 | 1 | 2 | 0 | 0 | 3 |
Total | 66 | 281 | 110 | 27 | 3 | 488 |
The 2002 Veterans Day weekend tornado outbreak was an unusually severe and expansive severe weather event across portions of the Central and Eastern United States from the evening hours of November 9 into the early morning hours of Veterans Day, November 11, 2002. A series of troughs tracked eastward across the United States, providing strong wind shear, while anomalously warm and unstable air surged northward into the Ohio River Valley. As a result, multiple tornadoes occurred across Arkansas, Tennessee, and Missouri on November 9. A far more widespread and severe event occurred the following day, with three distinct tornado outbreaks focused across areas from Illinois to Pennsylvania; Tennessee and Kentucky; and areas from Mississippi to South Carolina. The most intense tornado of the outbreak was a violent F4 tornado that occurred near Van Wert, Ohio. A total of 76 tornadoes occurred during the 3-day period, collectively resulting in 36 deaths and 303 injuries. As of 2022, the event ranks as the third-largest tornado outbreak on record in November.
This page documents notable tornadoes and tornado outbreaks worldwide in 2004. Strong and destructive tornadoes form most frequently in the United States, Bangladesh, and Eastern India, but they can occur almost anywhere under the right conditions. Tornadoes also develop occasionally in southern Canada during the Northern Hemisphere's summer and somewhat regularly at other times of the year across Europe, Asia, and Australia. Tornadic events are often accompanied with other forms of severe weather, including strong thunderstorms, strong winds, and hail.
This page documents notable tornadoes and tornado outbreaks worldwide in 2001. Strong and destructive tornadoes form most frequently in the United States, Bangladesh, and Eastern India, but they can occur almost anywhere under the right conditions. Tornadoes also develop occasionally in southern Canada during the Northern Hemisphere's summer and somewhat regularly at other times of the year across Europe, Asia, and Australia. Tornadic events are often accompanied with other forms of severe weather, including strong thunderstorms, strong winds, and hail.
This page documents the tornadoes and tornado outbreaks of 1999, primarily in the United States. Most tornadoes form in the U.S., although some events may take place internationally, particularly in parts of neighboring southern Canada during the Northern Hemisphere's summer season, as well as Europe. One particular event, the Bridge Creek-Moore, Oklahoma F5 tornado, produced the highest wind speed ever recorded on Earth, which was 301 ± 20 mph (484 ± 32 km/h).
One of several tornado outbreaks in the United States to take place during the record month of April 2011, 49 tornadoes were produced across the Midwest and Southeast from April 9–11. Widespread damage took place; however, no fatalities resulted from the event due to timely warnings. In Wisconsin, 16 tornadoes touched down, ranking this outbreak as the state's largest April event on record as well as one of the largest single-day events during the course of any year. The strongest tornado of the outbreak was an EF4 tornado that touched down west of Pocahontas, Iowa on April 9, a short-lived satellite to a long-track EF3 tornado. Between 0256 and 0258 UTC that day, five tornadoes were on the ground simultaneously in Pocahontas County, Iowa, all of which were from one supercell thunderstorm. Other tornadoes impacted parts of eastern Kentucky and Tennessee on April 9, hours before the event in Iowa.
From June 12 to June 13, 2013, two derechos occurred across different areas of the Eastern United States. The initial derecho formed on the afternoon of June 12 and tracked across a large section of the Midwestern United States, the central Appalachians, and the Mid-Atlantic states before moving into the Atlantic Ocean during the morning of June 13. A second, more widespread and intense derecho occurred on June 13 across the Southeastern United States, resulting in major wind damage across North Carolina, Virginia, and Maryland, among other states. These storms caused at least three deaths and extensive damage property damage – resulting from both tornadoes and straight-line winds – from Iowa to South Carolina. 28 tornadoes touched down in Iowa, Illinois, Ohio, Georgia, North Carolina, Maryland, Virginia, and Tennessee. One of the tornadoes in Iowa was rated as a high-end EF3, destroying a restaurant and two houses. One person was injured by another tornado, rated EF2, in Carroll County, Illinois, and nine people were injured by an EF1 in Cherokee County, Georgia.
This page documents the tornadoes and tornado outbreaks of 2014. Strong and destructive tornadoes form most frequently in the United States, Bangladesh, Brazil, and Eastern India, but they can occur almost anywhere under the right conditions. Tornadoes also appear regularly in neighboring southern Canada during the Northern Hemisphere's summer season, and somewhat regularly in Europe, Asia, and Australia.
This page documents notable tornadoes and tornado outbreaks worldwide in 2016. Strong and destructive tornadoes form most frequently in the United States, Bangladesh, Brazil and Eastern India, but they can occur almost anywhere under the right conditions. Tornadoes also develop occasionally in southern Canada during the Northern Hemisphere's summer and somewhat regularly at other times of the year across Europe, Asia, and Australia. Tornadic events are often accompanied with other forms of severe weather, including strong thunderstorms, strong winds, and hail. There were 1,059 tornadoes reported in the United States in 2016, of which 974 were confirmed. Worldwide, 133 fatalities were reported: 100 in China, 18 in the United States, five in Uruguay, four in Brazil and two in Italy, Russia and Indonesia each.
A significant severe weather and tornado outbreak affected the Southern United States between December 16–17, 2019. Discrete supercells developed in the early morning on December 16 and moved northeast, spawning multiple strong, long-tracked tornadoes in cities such as Alexandria and in Laurel before congealing into an eastward-moving squall line. During the outbreak, the National Weather Service issued several PDS tornado warnings as well as a rare tornado emergency for Alexandria. In addition to this, the Storm Prediction Center issued six tornado watches for the outbreak. The event happened to take place on the same date of another outbreak in a similar area 19 years earlier.
The 2002 Van Wert–Roselms tornado was a violent tornado that struck the city of Van Wert and the community of Roselms, Ohio on November 10, 2002. The National Weather Service rated the worst of the damage F4 on the Fujita scale, near and within the Van Wert area. In Van Wert, hundreds of homes and businesses were damaged or destroyed, with several homes and businesses sustaining F4 damage. Among these businesses, a movie theater, was leveled by the tornado, but the sixty people attending the feature inside the theater survived. In Roselms, only one single structure was left standing. The tornado killed four people, injured seventeen others, and was credited for over $30 million in damages.