EP1 · Severe Convective Storms
Four hundred thousand severe weather reports mapped and counted: where hail, tornadoes and straight-line winds concentrate, and how the seasons drive them.
Alert me when
A severe convective storm is an intense thunderstorm that turns violent: hail, tornadoes and damaging straight-line winds. The central United States is their global heartland, where the ingredients line up more reliably than anywhere on Earth.
Each report is graded on its own scale. This record holds the ground truth: what was observed, where, and how big.
The three perils split their harm differently, which is why severe convection now sits on insurers' risk registers as their fastest-growing weather loss.
Hail is the quiet giant: rarely fatal, but it batters roofs, cars and solar arrays across whole metropolitan areas at once, and it drives the majority of insured convective losses. Tornadoes are the killer, concentrating destruction into narrow, total-loss corridors. Straight-line winds are the volume, the most frequent report of the three. The map plots each type on its own; the strip below counts them by year.
Every severe hail, tornado and damaging-wind report NOAA logged, by year. Wind reports are the most numerous, hail the loss driver, tornadoes the smallest count but the deadliest. Source: NOAA Storm Prediction Center.
Every severe hail, tornado and wind report since 2010: type, date, place, size or rating, sortable and filterable.
Around 360 tornadoes in four days, four of them EF5. The 25-28 April 2011 outbreak killed about 321 people and set the roughly ten billion dollar insured benchmark for convective storms.