The Great Natchez Tornado of May 7th, 1840
Near 1pm on the afternoon of May 7th, 1840 a thunderstorm that produced one of the most violent tornadoes in recorded history began to form just southwest of Natchez, Mississippi. Near 2pm the storm dropped what was likely a massive twister as it crossed the Mississippi River into the southwest part of the state. In 1840, the National Weather Service did not yet exist and even the inception of the Weather Bureau still had about 30 years to go.
The people of Natchez literally had no warning, save for some reports of thunder and lightning. Storms with gusty winds had blown through New Orleans earlier in the morning, but this wasn't unusual weather for the Deep South in the month of May. Reports and damage paths from 1840 are hardly reliable, but there was some evidence to suggest that the legendary tornado may have approached 2 miles wide at its largest. In his monumental work on historical tornadoes, Thomas Grazulis (1993) quoted an eyewitness from a journal, "the air was black with whirling eddies of walls, roofs, chimneys and huge timbers from distant ruins...all shot through the air as if thrown from a mighty catapult." One of the most dramatic pieces of lore from this event was the notion that the tornado was so strong, it actually sucked the moisture from leaves on the local trees.
An artist's rendition of the storm approaching a steamboat.
The central and northern parts of the city were hit hardest and the tornado caused approximately 317 deaths, officially making it the second most deadly tornado in American history behind the infamous Tri-State Tornado of 1925. An interesting fact about the tornado is that for much of its life-cycle, it basically followed parallel with the Mississippi River and the vast majority of deaths were actually caused by overturned steam boats (269 deaths). Other rural areas could have been effected by the same tornado in Louisiana and Mississippi, but it is almost impossible to say if this damage was caused by the Natchez twister. In reality, the 317 deaths could be an estimate on the small side. It is also important to note that slave deaths were not properly reported a this time, making it likely that the death toll was much worse. Some estimates have shown that the damage would have approached $100 million today, but if one added the present population density into the equation, the total could have arguably eclipsed $1 billion. Most weather historians believe the Natchez tornado would have easily ranked as an F5 or EF5. Before the twister, Natchez was a huge center for cotton trade and commerce. They city did rebuild, but it was never quite the same.
An account form the Natchez Courier, the day after.