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 Precipitation Totals from Eastern Australia, March 16 - 23, 2021
During the week ending on March 23, 2021, two locations in Australia experienced unusually high rainfall totals. According to news reports a persistent system brought flooding rains to Australia's east coast from Brisbane to Sydney and points further south. The preliminary estimate from NASA's multi-satellite global precipitation analysis is that more than 24 inches fell just off the coast of Australia in 7 days with accumulations in coastal areas exceeding 16 inches. Near the Strzelecki Desert in central Australia, a storm system brought 8 inches of precipitation during the same 7-day period. Most of the rain fell during a 3-day period (0000 UTC on 20 March to 2359 UTC on 22 March).
IMERG Sees Winter Storms Impact the Southern U.S.
In mid-February 2021, large areas of the Continental United States experienced extreme cold temperatures as a result of a strong Arctic high pressure system. The cold temperatures were accompanied by several pulses of precipitation over the Southeast US through the mid-Atlantic, as well as the Pacific Northwest. The combination of cold temperatures and precipitation resulted in widespread power outages to millions of people in Texas, Kentucky, West Virginia, and Oregon, among other states.
IMERG Captures Rainfall from Tropical Cyclone Ana in Fiji
NASA combined data from multiple satellites to estimate the rainfall from Tropical Cyclone Ana in the Southwest Pacific Ocean amid an ongoing Madden-Julian Oscillation (MJO) event. The Madden-Julian Oscillation is a 20 to 90 day pattern of alternating wet and dry conditions that often begins in the tropical Indian Ocean and moves eastward into the Pacific. This animation shows rainfall rates (blue/yellow shading) and rainfall accumulations (green shading) at half-hourly intervals from January 26 - February 2, 2021, using NASA's IMERG algorithm, overlaid on shades of white/gray from NOAA
IMERG Rainfall Total from Week of Jan 25 2021
NASA combined data from multiple satellites to estimate the rainfall from an "atmospheric river" event over the U.S. West Coast in near real-time at half-hourly intervals from January 25 - 29, 2021. Atmospheric rivers are long, narrow corridors of water vapor that can lead to heavy precipitation when they encounter land. This animation shows estimated rainfall rates in blue and yellow shading and total rainfall accumulations in green shading, from NASA's IMERG algorithm, overlaid on shades of white and gray from NOAA infrared satellite data which shows cloudiness. On January 25, 2021, a low
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