Tropical Cyclones

The GPM Mission provides insight into how and why some tropical cyclones intensify and others weaken as they move from tropical to mid-latitude systems. The GPM Core Observatory’s GMI and DPR instruments allow scientists to study the internal structure of storms throughout their life cycle, and view how they change over time.

IMERG rainfall totals from Cyclone Freddy
Tropical Cyclone Freddy first made landfall along the east coast of Madagascar just north of the town of Mananjary on Feb. 21, 2023, as a Category 3 cyclone with average winds reported at ~81 mph (130 km/h) and gusts up to ~112 mph (180 km/h). After crossing over Madagascar Freddy continued westward over the Mozambique Channel before making landfall again along the east coast of Mozambique just south of Vilankulos as a moderate tropical storm with sustained winds estimated at 50 mph. Despite being weaker at landfall, Freddy caused widespread flooding across parts of Mozambique due to the storm stalling out near the coast after making landfall. Incredibly, Freddy drifted back out over the Mozambique Channel, nearly making landfall along the southwest coast of Madagascar. It then changed direction, re-intensified, weakened, re-intensified one last time, and made landfall once again on March 11 near Quelimane, Mozambique, as a Category 1 cyclone with sustained winds reported at 90 mph.
GPM overpass of tropical storm Nicole
Hurricane Nicole hit the East Coast of Florida early yesterday morning, November 10th, 2022, at 3:00 am (EST) just south of Vero Beach at North Hutchinson Island. But, unlike Hurricane Ian which came ashore in late September as a powerful Category 4 storm that devasted parts of southwest Florida, Nicole made landfall as minimal Category 1 storm. Though far less intense, Nicole has still brought some heavy rain and gusty winds to the region. Nicole originated from a non-tropical low pressure system over the southwestern Atlantic. As a result, when the National Hurricane Center (NHC) was first
IMERG analysis of Hurricane Ian
On Sept. 30, 2022, Hurricane Ian was approaching South Carolina, which was one day after Ian finished its west-to-east crossing of Florida. NASA has been estimating Hurricane Ian's precipitation over land and ocean, which complements the array of detailed observations collected by NOAA and other agencies of Ian's impact over land.
GPM overpass of Hurricane Ian on Sept. 26, 2022
Hurricane Ian became one of the strongest hurricanes on record to strike Florida when it made landfall Wednesday, Sept. 28th, 2022, around 3:10 pm (EDT) as a Category 4 storm near Cayo Costa, FL, about 20 miles west-southwest of Punta Gorda on Florida’s southwest coast. This same area was hit hard by Hurricane Charley in 2004, which also made landfall as a strong Category 4 storm. Both storms passed over and were intensified by the deep, warm waters of the southeastern Gulf of Mexico. Ian originated from a tropical easterly wave that propagated westward off the coast of Africa across the
IMERG precipitation totals from Hurricane Ian
Hurricane Ian formed in the Caribbean Sea on Sept. 26, 2022. Ian intensified to Category 3 hurricane on the Saffir-Simpson scale by the time it made landfall in western Cuba early the next day. NASA's near real-time IMERG algorithm was used to estimate the precipitation from Ian during its formation and intensification. IMERG shows that Ian's largest rainfall accumulation so far, over 12 inches, occurred while it was only a tropical storm and not yet a hurricane. The National Hurricane Center provided an estimate of the distance that tropical storm-force winds extended from Ian's low-pressure
GPM overpass of Hurricane Fiona on Sept. 23, 2022.
After leaving the Caribbean, Hurricane Fiona became both the strongest and the first major hurricane of the 2022 Atlantic hurricane season as it made its way northward through the western Atlantic. Fiona began as an African easterly wave that moved across the tropical Atlantic in the direction of the Caribbean. While still about 800 miles east of the Leeward Isles, this wave organized into a tropical depression on Sept.14th. Later that same day, the depression strengthened and became Tropical Storm Fiona. Fiona remained a moderate tropical storm as it passed through the Leeward Isles on the
IMERG precipitation estimates from Hurricane Fiona
In September 2022, Hurricane Fiona had impacts in the Caribbean, on Bermuda, and in Canada. NASA's satellites and science algorithms helped to monitor this hurricane in near real time.
GPM overpass of Typhoon Nanmadol
Super Typhoon Nanmadol became one of the strongest typhoons to threaten Japan since records began in 1951. Nanmadol began as a tropical disturbance, basically an area of active thunderstorms, on September 11th southeast of Iwo Jima about midway between Tokyo and Guam. After moving to the southwest for 2 days, this disturbance became better organized and formed into a depression on the 13th. The system then made a counterclockwise loop, moving first back to the northeast before turning back again towards the west. Over this time, the system slowly intensified, becoming Tropical Storm Nanmadol
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 Comparison of Typhoon Mindulle and Hurricane Sam
From late Sept. through early Oct. 2021, two powerful storms churned over the Pacific and Atlantic Oceans: Typhoon Mindulle, which peaked as a Category 5 storm, and Hurricane Sam, a Category 4 hurricane and one of the longest-lived hurricane-strength storms on record over the Atlantic Ocean. While neither storm posed a direct threat to land, Mindulle brushed by eastern Japan, leaving heavy rainfall accumulations in the area near Tokyo. Despite the fact that neither storm made landfall, the storms’ slow-motion tracks across warm ocean waters allows an opportunity to observe how the strong winds