NASA measures Cyclone Chapala's heavy rains across Arabian Sea to Yemen
The Global Precipitation Measurement mission or GPM core satellite added up the totals as Cyclone Chapala dropped a lot of rain moving across the Arabian Sea to landfall in Yemen.
Cyclone Chapala formed into a rare but powerful Category 4 cyclone in the Arabian Sea with winds at one time estimated at 155 mph by the Joint Typhoon Warning Center (JTWC) back on Oct. 30. Chapala made its initial landfall along the south coast of Yemen on November 3 west of the port city of Mukulla at around 09:00 UTC as a Category 1 cyclone with maximum sustained winds estimated at 75 mph by JTWC, making it the first Category 1 cyclone on record to strike Yemen. The last cyclone to strike the Arabian Peninsula was Cyclone Phet, which hit eastern Oman back in 2010.
In addition to strong gusty winds Chapala brought heavy rains and flooding to a country that is predominantly dry desert. Although on average the western highlands receive between 10 and 15 inches of rain per year, much of eastern Yemen receives less and 5 inches per year with coastal areas often getting less than 2 inches per year.
The Integrated Multi-satellitE Retrievals for GPM or IMERG is used to make estimates of precipitation from a combination of passive microwave sensors, including the GMI microwave sensor onboard the GPM satellite, and geostationary IR (infrared) data.
At NASA's Goddard Space Flight Center in Greenbelt, Maryland, the data was used to create an image that showed IMERG rainfall estimates from Oct. 28 at 18:00 UTC to Nov. 3 at 08:30 UTC for Yemen, the Gulf of Aden and the surrounding region in association with Cyclone Chapala.
IMERG showed rainfall amounts between 5 to 15 inches over south central Yemen and along the coast to the right of where Chapala made landfall. Areas in eastern Yemen appear to have received at least 3 inches of rain. The highest total over Yemen was 398 mm (~16 inches).
Most of these totals are the equivalent of a year's worth of precipitation or more. So far at least 3 persons are reported to have died and 200 injured as a result of the storm on the island of Socotra located about 150 miles east of the Horn of Africa. IMERG rainfall totals for Socotra are between 12 and 20 inches of rain.
GPM is a joint missions between NASA and the Japanese space agency JAXA.