Hurricane Ida: August 29 to September 1
Crashing on the Louisiana Gulf Coast repeatedly on August 29 as a Category 4 hurricane, it was one of three recorded hurricanes to make landfall in Louisiana with winds over 150 mph . Hurricane Laura did the same last year, but before Laura you have to go back to 1856 to find a storm of the same strength. New Orleans was just far enough east of the landing to avoid catastrophic impacts, but even there power was cut off in many neighborhoods for almost a week.
Winds inside the storm weakened as it moved north into the United States, and days later interacted with a system coming in from the north, causing massive flash floods in the North-east. In a large area between New York City and the northern Philadelphia suburbs, 7 to 9 inches of rain fell in 24 hours.
Tornado outbreak: December 10
Eight states reported tornadoes, and 61 tornadoes have been confirmed in this epidemic. Tornado outbreaks of this magnitude are rare, but particularly in December. The strongest of these tornadoes ravaged Mayfield, Ky. Rated as an EF-4, it had an estimated maximum wind speed of 190 mph and traveled an astonishing distance of 165 miles.