Floods

On Sept. 4, 2023, a low-pressure system developed over southeastern Europe that would lead to devastating floods over Greece and other parts of the region. The system was given the name “Daniel” by local meteorological agencies. Daniel was dynamically driven by strong cyclonic flow in the upper-level winds over southeastern Europe. The upper-levels winds combined with low-level winds from the northeast which supplied moisture from the unusually warm waters of the Aegean and Black Seas to central Greece. According to satellite infrared and microwave estimates from NASA's MUR and NOAA’s OISST v2

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.

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

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

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).

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

From July 3-9, 2020, NASA’s IMERG algorithm continued to observe the heavy precipitation that fell as part of the seasonal Meiyu-Baiu rains (“plum rains”) in east Asia. Weekly totals reached their regional maxima over the island of Kyushu in southern Japan. About half of the island of Kyushu received over 45 cm (~18 inches) of rain. The majority of Honshu, Japan’s main island, as well as Shikoku to its south, were also impacted by the rains, receiving from 10-25 cm, depending on the location. Additionally, large areas of eastern China were also covered by the plum rains during this weekly

This animation shows NASA IMERG rain rates (blue shading) and accumulations (green shading) near Kyushu island, in the southwest of Japan from June 29 - July 5, 2020. Devastating floods and landslides swept through parts of Kyushu on July 4, 2020, resulting in over 40 deaths and orders for hundreds of thousands of people to evacuate their homes according to media reports. Download video (right-click -> Save As) The rains that triggered the flooding occurred in the context of the Meiyu-Baiu rainy season, which arrives in east Asia every year from June to mid-July. “Meiyu” and “Baiu” are the