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What is the difference between a tornado and a hurricane?

Tornadoes and hurricanes appear to be similar in their general structure. Both are characterized by extremely strong horizontal winds swirling around the center, strong upward motion dominating the circulation with some downward motion in the center. The tangential winds far exceed the radial inflow or the vertical motion, and can cause much damage. Hurricanes always rotate counterclockwise in the northern hemisphere (clockwise in the southern), the direction of their rotation being determined by the Earth's rotation. This is almost always true of tornadoes too, although on rare occasions "anticyclonic" tornadoes spinning in the opposite direction do occur (tornadic circulation is determined by the local winds). This is where the similarities end.

The most obvious difference between tornadoes and hurricanes is that they have drastically different scales. They form under different circumstances and have different impacts on the environment. Tornadoes are "small-scale circulations", the largest observed horizontal dimensions in the most severe cases being on the order of 1 to 1.5 miles. They most often form in association with severe thunderstorms which develop in the high wind-shear environment of the Central Plains during spring and early summer, when the large-scale wind flow provides favorable conditions for the sometimes violent clash between the moist warm air from the Gulf of Mexico with the cold dry continental air coming from the northwest. However, tornadoes can form in many different circumstances and places around the globe. Hurricane landfalls are often accompanied by multiple tornadoes. While tornadoes can cause much havoc on the ground (tornadic wind speeds have been estimated at 100 to more than 300 mph), they have very short lifetimes (on the order of minutes), and travel short distances. They have very little impact on the evolution of the surrounding storm, and basically do not affect the large-scale environment at all. Hurricanes, on the other hand, are large-scale circulations with horizontal dimensions from 60 to well over 1000 miles in diameter. They form at low latitudes, generally between 5 and 20 degrees, but never right at the equator. They always form over the warm waters of the tropical oceans (sea-surface temperatures must be above 26.5° C, or about 76° F) where they draw their energy. They travel thousands of miles, persist over several days, and, during their lifetime, transport significant amounts of heat from the surface to the high altitudes of the tropical atmosphere. While their sporadic occurrence prevents them from drastically impacting the large-scale circulation, they still affect it in ways which must be accounted for and need to be better understood.

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IMERG Total from Cyclone Gati
On November 22, 2020, Cyclone Gati became the strongest storm to hit Somalia since satellite records began five decades ago. Gati made landfall with maximum sustained winds of 170 kilometers (105 miles) per hour, a category 2 storm on the Saffir-Simpson scale. The storm brought more than a year’s worth of rain to the region in two days. Local authorities report at least eight people were killed and thousands have been displaced. The map above shows rainfall accumulation from November 21-23, 2020. These data are remotely-sensed estimates that come from the Integrated Multi-Satellite Retrievals
IMERG Rainfall Totals from Eta & Iota, November 1 - 18
The record-breaking 2020 Atlantic hurricane season, aided by the ongoing La Niña, is officially the most active Atlantic hurricane season on record, surpassing the 2005 season in the total number of named storms with 30 to date. Incredibly, the latest storm Iota wasn’t just another named storm, but a powerful Category 5 hurricane and the strongest storm of the season. It was also only the 2nd Category 5 storm to occur in the month of November on record, the other being in 1932. The warm waters of the Caribbean continue to serve as a breeding ground for late-season storms this season. Iota
GPM Overpass of Hurricane Eta Nov. 11 2020
After a long and meandering journey over Central America, across central Cuba, and through the Florida Keys, Eta, the 28th named storm and 12th hurricane of the 2020 Atlantic hurricane season, wound up nearly stationary as a moderate tropical storm in the southeastern Gulf of Mexico just north of the western tip of Cuba on the morning of November 10th. Before long however, a deep layer trough located over the western third of the US began to shift eastward, and by the afternoon of the 10th, it started to pull Eta back towards the north and the west coast of the Florida peninsula. As it did so
Hurricane Eta over Florida
After striking the northeast coast of Nicaragua as a powerful Category 4 storm back on November 3, Hurricane Eta weakened rapidly over Central America but still brought major flooding and triggered numerous landslides that so far have resulted in at least 250 fatalities across the region, according to media reports. Eta was down to a tropical depression when the center re-emerged over the northwestern Caribbean on the evening of November 5. An upper-level trough over the Gulf of Mexico first steered Eta northeastward towards Cuba on the 6th. Because it was disorganized after its trek across
Hurricane Eta IMERG Screenshot
The extremely active 2020 Atlantic hurricane season, aided by the ongoing La Niña, continues on. After Hurricane Zeta made landfall along the northern part of the Gulf Coast, yet another hurricane has arisen - Hurricane Eta, the strongest of the season. Like Zeta, Eta also formed in the Caribbean, where sea surface temperatures are still running quite warm at around 29° C, almost a full degree above average and well above the typical 26° C needed for tropical cyclone development. But while Zeta turned north into the Gulf of Mexico, Eta moved westward where it delivered powerful winds and