April 1 edit
1997: A major nor'easter dumped an unprecedented amount of late-season snow on parts of the Eastern United States, including more than 2 feet (60 cm) in Boston, Massachusetts.
April 2 edit
1957: The first day of a 4-day tornado outbreak struck Texas and Oklahoma, including a tornado that caused severe damage and killed 10 people in the Dallas–Fort Worth metroplex.
April 3 edit
1974: The Super Outbreak, one of the most severe tornado outbreaks in world history, spawned 148 tornadoes, including 30 violent tornadoes, in the east-central United States and Windsor, Ontario, Canada. More than 300 people were killed, and $3.5 billion (2005 USD) in damage was reported.
April 4 edit
1978: Cyclone Alby, the most damaging tropical cyclone to impact Western Australia on record, brought widespread damage to homes and crops and wind gusts as high as 150 kilometres per hour (93 mph) in Albany.
April 5 edit
1972: An unusual tornado tracked from Oregon to Washington, killing 6 people.
April 6 edit
2020: Cyclone Harold, one of the strongest tropical cyclones in history to strike Vanuatu, made landfall on Espiritu Santo with 10-minute maximum sustained winds of 115 knots (215 km/h; 130 mph).
April 7 edit
1922: The first mid-air collision of airliners in history occurred over Picardie, France, due to thick fog.
April 8 edit
1998: An F5 tornado, the second in the area's history, killed 32 people near Birmingham, Alabama.
April 9 edit
2003: INSAT-3A, a weather and communications satellite built by the Indian Space Research Organisation, was launched into geostationary orbit.
April 10 edit
1991: The Angola Cyclone, the first tropical cyclone ever observed over the southern Atlantic Ocean, formed just off the coast of Angola.
April 11 edit
1854: John Park Finley, a pioneer in reporting and documenting tornadoes in the United States, was born.
April 12 edit
2020: A major tornado outbreak struck the Southeastern United States on the Easter holiday, killing 32 people over two days.
April 13 edit
2014: After skirting the coast of Queensland for two days, Cyclone Ita began moving southeastward over the Coral Sea near Mackay. Ita caused A$1.1 billion in damage in Australia.
April 14 edit
2017: Flash floods due to heavy rain killed more than 40 people in northwestern Iran, mostly in the East Azerbaijan Province.
April 15 edit
1927: In New Orleans, 15 inches (380 mm) of rain fell in 18 hours, worsening an already historic flood and leading to the fateful (and ultimately unnecessary) decision to intentionally breach a levee south of the city.
April 16 edit
2011: The final day of a three-day tornado outbreak brought dozens of tornadoes to the Mid-Atlantic and Southeastern United States, killing 26 people.
April 17 edit
1979: Flooding along the Pearl River in Jackson, Mississippi crested at 43.28 feet (13.19 m), exceeding the previous record by more than 5 feet (1.5 m).
April 18 edit
2014: An avalanche killed 16 Sherpa guides working on Mount Everest.
April 19 edit
2000: Cyclone Rosita, one of the strongest tropical cyclones ever to strike the Kimberley region of Western Australia, reached Category 5 intensity (Australian scale), making landfall just after midnight near Broome.
April 20 edit
1967: The ESSA-5 weather satellite was launched.
April 21 edit
2003: Tropical Storm Ana transformed from a subtropical cyclone to a tropical cyclone, becoming the only such storm ever recorded in the northern Atlantic Ocean in April.
April 22: Earth Day edit
2011: A nighttime tornado, caused major damage in parts of St. Louis, Missouri, including Lambert-St. Louis International Airport, but amazingly caused no deaths and few injuries.
April 23 edit
1792: John Thomas Romney Robinson, inventor of the cup-anemometer, was born in Dublin, Ireland.
April 24 edit
2010: A deadly tornado tracked 149 miles (240 km) across Louisiana and Mississippi, killing 10 people.
April 25 edit
2014: An outbreak of 11 tornadoes struck North Carolina, damaging more than 300 homes and killing one person.
April 26 edit
1998: Cyclone Alan which had been impacting French Polynesia with several days of strong winds and heavy rain that killed 10 people, dissipated west of Tahiti.
April 27 edit
2011: The deadliest American tornado outbreak in 76 years killed more than 300 people in the Southern United States.
April 28 edit
1983: The GOES 6 weather satellite was launched. Part of the Geostationary Operational Environmental Satellite program, GOES 6 would provide weather forecasting data to the United States until its main imaging instrument failed in 1989.
April 29 edit
1991: The second-deadliest tropical cyclone in world history struck the Chittagong area of Bangladesh, killing at least 138,000 people.
April 30: End of the Southern Hemisphere tropical cyclone seasons except for the Mauritius and Seychelles region edit
1924: Dozens of deadly tornadoes killed 111 people across the Southeastern United States, including one F4 tornado which killed 53 people in South Carolina over a 105-mile (169 km) path.