What is the difference between a tornado and a hurricane?

Both tornadoes and hurricanes are characterized by extremely strong horizontal winds that swirl around their center and by a ring of strong upward motion surrounding downward motion in their center. In both tornadoes and hurricanes, the tangential wind speed far exceeds the speed of radial inflow or of vertical motion.

Hurricanes always and tornadoes usually rotate counterclockwise in the northern hemisphere and clockwise in the southern hemisphere. The Earth's rotation determines this direction for the storms' rotation in each hemisphere. Local winds are sometimes able to cause a tornado to form that spins in the opposite direction from the typical direction for that hemisphere.

The most obvious difference between a tornadoe and hurricane is that a hurricane's horizontal scale is about a thousand times larger than a tornado. In addition, hurricanes and tornadoes form under different circumstances and have different impacts on the atmosphere.

Tornadoes are small-scale circulations, that are rarely more than a few hundred feet across when they touch the ground. Most tornadoes grow out of severe thunderstorms that develop in the high wind-shear environment of the United States Central Plains during spring and early summer.  Many tornadoes form when the large-scale wind flow leads to a violent clash between moist, warm air traveling north from the Gulf of Mexico and cold, dry, continental air coming from the United States Northwest. Tornadoes can also form in many other locations and from other forcing factors. For example, a hurricane making landfall may trigger many tornadoes to form.

Tornado wind speeds may reach 100 to 300 mph and cause havoc on the ground, but tornadoes typically last only a few minutes and rarely travel more than 10 or 20 miles along the ground. Tornadoes have little impact on storms that spawn them or collectively on the global circulation of the atmosphere.

Hurricanes, on the other hand, are large-scale circulations that are 60 to over 1,000 miles across. Hurricanes form near the Equator, generally between 5 and 20 degrees latitude, but never right on the Equator. Hurricanes always form over the warm waters of the tropical oceans and generally where the sea-surface temperature exceeds 26.5°C (76°F).

A hurricane may travel thousands of miles and persist over several days or weeks. During its lifetime, a hurricane will transport a significant amount of heat up from the ocean surface and into the upper troposphere or even lower stratosphere. Even though hurricanes form only sporadically, they do affect the global atmosphere's circulation in measurable ways, although this is still an active area of research.

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IMERG totals from twin cyclones in the Indian Ocean
Over the past several days, a relatively rare event occurred in the eastern Indian Ocean: the formation of “twin” tropical cyclones. Tropical Cylones Karim and Asani formed at nearly the exact same time (06:00 UTC and 06:30 UTC, 12:00 pm and 12:30 pm local time) on May 7 on opposite sides of the Equator. Karim officially formed first in the southern hemisphere (SH) followed immediately by Asani in the northern hemisphere (NH). At first glance, the cyclones appear to be mirror images of one another with Asani rotating counterclockwise in the NH and Karim rotating clockwise in the SH roughly
IMERG rainfall totals in South Africa, April 5 - 18, 2022.
An upper-level area of low pressure tapped into the warm waters of the South Indian Ocean to bring heavy rains and flooding to parts of South Africa during the second week of April. The event unfolded when an upper-level trough of low pressure embedded within the midlatitude westerlies traversed the southern part of Africa from west to east. As the trough approached the east coast of South Africa, an area of low pressure became detached from the main flow, this “cut off” low then drifted over the warm waters of the Agulhas Current, which channels warmer waters from the tropical Indian Ocean
IMERG Rainfall Totals from Australian :"Rain Bomb" in March 2022
The below animation shows surface rainfall estimates from NASA’s IMERG multi-satellite precipitation product for the week starting on Feb. 22, 2022 at 0000 UTC and ending on Feb. 28, 2022 at 2330 UTC. Areas shaded in blue and yellow show three-hour average snapshots of IMERG rain rates every half-hour overlaid on cloudiness (shown in white/gray) based on geosynchronous satellite infrared observations. Below the rain rates and cloudiness data, IMERG rainfall accumulations are shown in green and purple. Tropical Cyclone Anika’s track is shown with a gray line based on data from the U.S. Navy-Air
IMERG rainfall totals from the Nov. 2021 atmospheric river.
The Pacific Northwest coast saw two atmospheric rivers (ARs) bring heavy rains from Nov. 10-16, 2021, resulting in severe flooding, landslides, and damage to infrastructure in the British Columbia province of Canada. ARs are long, narrow corridors of water vapor that travel vast distances above the ocean from warm, tropical regions to higher latitudes, where they often release their moisture as rainfall when they reach land areas. While ARs occur across the globe, this year has been notable for several strong events that have impacted the Pacific Northwest coast. The two atmospheric rivers in
IMERG rainfall totals from recent atmospheric river.
The Pacific Northwest experienced a memorable series of storms in late Oct. 2021 as several low-pressure systems rolled in from the northeast Pacific Ocean. One of the systems was classified by meteorologists as a “bomb cyclone”, meaning that its central pressure (an indication of storm strength) had dropped particularly rapidly in a short time period. At its minimum pressure (highest strength), the system was reported by the National Weather Service to have had the lowest pressure of a system over the northeastern Pacific Ocean since reliable observations began in 1974. The system was notable