The U.S. state of Arizona experiences four tornadoes on average each year. Tornadoes in Arizona are usually weak, F0 to F1 range; EF0 and EF1 Enhanced Fujita scale range. However, Arizona exceptionally experiences rare significant events. Including an F2 tornado in Pima that killed two people in 1964, and another deadly tornado event in Pima in 1974 that killed a man; this tornado was rated F1, though meteorologist Thomas P. Grazulis believes it is F2. Arizona has experienced five (E)F3 tornadoes through out the years, and during October 6, 2010. A tornado outbreak produced two EF3 rated tornadoes and five other tornadoes. There have been over 200 tornadoes that were reported in Arizona and there are over 120 injuries related to tornadoes in the state.
Climatology Each year on average, four tornadoes touch down in Arizona. However, the state's most prolific year was in 1972 and 2010, when the state experienced 18 tornadoes. Tornadoes in Arizona are also more likely to happen during monsoon season, which is usually July, August or September, but tornadoes can still happen in any month in Arizona. Due to the many rural areas of Arizona, its possible that unreported tornadoes have appeared. The most likely tornado to happen in Arizona are non-supercell tornadoes, which is typically a landspout.
Events
Pre-1950
April 22, 1874 – A tornado struck California causing damage, it then moved into Yuma County, animals in its path vanished. August 23, 1880 – A tornado struck Fort Mohave; it lasted for about 5 minutes as it destroyed a business. Four men were killed when the building collapsed and eight more were injured. The tornado then damaged a roof from a adobe and destroyed two more buildings. April 8, 1926 – An F2 tornado destroyed six small buildings in Maricopa County, one person was injured.
1950-1959
November 14, 1952 – An unrated tornado struck Yavapai County. March 4, 1954 – An unrated tornado struck Pima County. August 8, 1954 – An unrated tornado struck Yavapai County. June 6, 1955 – An F1 tornado struck Maricopa County causing at least $25.000 in damage. July 12, 1956 – An unrated tornado struck Cochise County. July 25, 1956 – Two tornadoes struck Maricopa County, the first being an unrated tornado causing $0.25 in property damage. The second being an F0 near Phoenix. April 29, 1957 – An unrated tornado struck Apache County. August 4, 1957 – An F3 tornado struck Maricopa County in a very rural area. The tornado damaged a service station. August 18, 1957 – An unrated tornado struck Coconino County. August 20, 1957 – An unrated tornado struck Coconino County in Santa Maria Mountains. August 29 , 1957 – An F0 tornado struck Maricopa County; filling station lost its roof and homes we're damaged. March 11, 1958 – An F0 tornado struck Maricopa County, the twister caused $25.000 in damage. March 12, 1958 – An F2 tornado damaged 18 homes North West of Tucson in Pima County; some lost their roofs. The tornado was described as an "inverted cone" with "all kinds of debris, sheet and garbage roaring outside". May 11, 1958 – An unrated tornado struck Maricopa County. July 24, 1958 – An unrated tornado struck Coconino County. The twister caused $2.500 in damage. September 24, 1958 – An unrated tornado struck Scottsdale in Maricopa County. August 17, 1959 – An F2 tornado struck Yuma County injuring one person. The tornado also caused at least $250.000K in damage. November 2, 1959 – An F1 tornado struck Yavapai County, causing at least $25.000 in damage.
1960-1969
June 10, 1960 – An unrated tornado struck Navajo County. September 9, 1960 – An unrated tornado struck Pinal County. July 22, 1961 – An F1 tornado struck Maricopa County leaving $25k in damage. July 27, 1961 – An F1 tornado struck Pima County, injuring one person. The tornado caused at least $250K in damage. September 8, 1961 – An F1 tornado struck Maricopa County injuring two people. The tornado caused at least $250.00K in damage. July 26, 1962 – An F0 tornado struck Yavapai County. October 17, 1962 – Two unrated tornadoes struck the state. The first was in Navajo County. The second was in Apache County. July 10, 1963 – An unrated tornado struck Cochise County. August 27, 1964 – A short lived and small F2 tornado struck the San Xavier Mission west of Tucson in Pima County, damaging an Indian village and destroyed four homes, a mother and her baby were killed when they were crushed by debris, and nine people were injured. This was the first official deadly tornado in Arizona. September 15, 1964 – An F0 tornado struck Pima County. July 27, 1966 – An F1 tornado struck near the Mexico border in Cochise County. Causing at least $25.00K in damage. July 30, 1966 – An F0 tornado struck Coconino County. August 9, 1966 – An F1 tornado struck Gila County, injuring nine people. The tornado caused at least $25.00K in damage. August 31, 1966 – An unrated tornado struck Cochise County. September 13, 1966 – An unrated tornado struck Yuma County near the California and Mexico border. July 16, 1967 – An F1 tornado struck Pinal County. The tornado caused at least $25.00K in damage. July 27, 1967 – An unrated tornado struck Maricopa County. August 5, 1967 – An unrated tornado struck Yavapai County. August 8, 1967 – An unrated tornado struck Coconino County. December 19, 1967 – An unrated tornado struck Maricopa County. July 4, 1968 – An F2 tornado struck Maricopa County injuring two people. The tornado caused at least $25.00K in damage. July 20, 1968 – Two tornadoes touched down across the state, the first was an unrated tornado struck Coconino County. The second was an F1 which injured 3 people in Maricopa County. October 3, 1968 – An F2 tornado struck Maricopa County. Injuring three people and leaving $250.00K in damage. November 1, 1968 – An unrated tornado struck Coconino County. February 22, 1969 – An unrated tornado struck Maricopa County. August 1, 1969 – Two tornadoes touched down in the state, the first was a F1 that struck Maricopa County injuring 2 people. The second was a F0 that struck Pima County. August 16, 1969 – An F1 tornado struck Pima County. The tornado caused at least $250.00K in damage.
1970-1979
July 19, 1970 – A tornado struck Maricopa County. August 8, 1970 – A tornado struck Pinal County. September 9, 1970 – An F1 tornado struck Maricopa County causing $25.00K in property damage. July 16, 1971 – An F1 tornado struck Cochise County, injuring 2 people. The tornado caused $25.00K in damage. July 17, 1971 – An F1 tornado struck Cochise County, causing at least $25.00K in damage. August 30, 1971 – An F2 tornado struck Tempe in Maricopa County damaging roofs, homes and trees. The tornado also destroyed 25 trailers. 41 people we're injured due to flying glass. The tornado caused at least $3.000M in damage. September 1, 1971 – Two F1 tornadoes touched down in the state. The first struck Pima County. The second struck Pinal County, this tornado caused $250.00K in damage. September 14, 1971 – An F2 tornado struck Maricopa County. The tornado caused $25.00K in damage. October 18, 1971 – An F1 tornado struck Maricopa County. The tornado caused $25.00K in damage. June 13, 1972 – An F0 struck Maricopa County. The tornado caused $25.00K in damage. June 21, 1972 – Six tornadoes touched down across the state. The first was an F0 that struck Pinal County. The second was an F1 that struck Pinal County injuring five people, the tornado damaged house trailers, trees, businesses and leaving $205k in damage. The third was an F0 that struck Pinal County. The fourth was an F0 that struck Maricopa County. The fifth tornado was an F3 that struck Eloy in Pinal County, injuring 18 people, including five that were hospitalized. The twister completely destroyed two mobile homes and severely damaged other buildings. The sixth tornado was an F2 that struck Maricopa County injuring three people. The tornado damaged at least 100 homes and some mobile homes, it was stated that "twin funnels were involved". This was the first damaging and significant tornado outbreak in Arizona. July 23, 1972 – An F0 tornado struck Maricopa County. August 8, 1972 – An F0 tornado struck Mohave County. August 10, 1972 – An F3 tornado struck Yavapai County. August 12, 1972 – An F1 tornado struck Maricopa County. September 9, 1972 – An F0 tornado struck Cochise County. September 10, 1972 – An F1 tornado touched down in Maricopa County; three homes lost their roofs entirely and many more were damaged. A young girl was cut by flying glass and caused $2.500M in damage. While the tornado is officially rated as an F1, tornado expert Thomas P. Grazulis rated the tornado as an F2. September 18, 1972 – Two tornadoes hit the state, the first was a F1 tornado that struck Mohave County, injuring one person and leaving $250.00K in damage. The second was a F1 that struck Yuma County leaving $25.00K in damage. October 4, 1972 – An F0 tornado struck Yuma County. October 18, 1972 – An F1 tornado struck Pinal County, with a width of , the tornado caused $25.00K in damage. April 20, 1973 – A short lived F0 tornado struck Navajo County. August 2, 1973 – An F0 tornado struck near Prescott in Yavapai County, the tornado moved across a lake shortly becoming a waterspout and quickly dissipated after making landfall. June 23, 1974 – Two tornadoes touched down in the state, the first was an F1 that struck Tucson in Pima County. The tornado struck a trailer park destroying 19 mobile homes and damaging 33 more severely. A man was killed and 40 people were injured. While the tornado is officially rated as an F1, tornado expert Thomas P. Grazulis rated the tornado as an F2. The second tornado was an F0 that struck Tucson in Pima County. June 24, 1974 – An F0 tornado struck west of Douglas in Cochise County. July 25, 1974 – An F0 struck Kearny in Pinal County. The tornado caused $25.00K in damage. August 8, 1974 – A small F1 tornado was reported by a pilot. It struck Mohave County. August 24, 1974 – A small F1 tornado struck Maricopa County, destroying a storage shed and leaving $2.5K in damage. October 23, 1974 – Two F1 tornadoes hit the state. The first touched down twice in San Manuel in Pinal County. The second tornado struck Pinal County, Arizona. October 27, 1974 – An F0 tornado briefly touched down in Petrified Forest National Park in Apache County. December 23, 1975 – An F1 tornado struck a rural area in Pima County, Arizona. May 4, 1976 – There was a outbreak of three tornadoes and all three struck Maricopa County. The first was a F0 that struck Scottsdale, the tornado had a length of . Shortly after the tornado dissipated, an F1 tornado struck the desert in Mesa, the twister was covered in dust and quickly dissipated when it entered a citrus grove. Approximately 48 minutes later, an F0 tornado briefly touched down in Fountain Hills. July 6, 1976 – An F0 tornado struck Seligman in Yavapai County. August 12, 1976 – An F1 tornado struck Colorado City in Mohave County. The tornado unroofed a hay shelter and lifted a house under construction. The tornado caused approximately $2.5K in damage. March 25, 1977 – An F1 tornado struck Maricopa County. July 19, 1977 – A tornado struck Ash Fork in Yavapai County, the tornado had a path length of . February 10, 1978 – Two tornadoes briefly touched down in Yuma County. March 14, 1979 – A tornado struck Mohave County, injuring three people and leaving $25K in damage. August 14, 1979 – An F0 tornado struck Apache County. September 28, 1979 – An F0 tornado touched down in the dessert area of Yuma, Arizona.
1980-1989
May 1, 1980 – Two tornadoes struck the state. The first being a F1 that touched down in Yavapai County and taking a path and then traveled into Coconino County and dissipated shortly after. Approximately 15 minutes later, another F1 tornado struck Coconino County.