GPM IMERG Adds Up Heavy Rainfall from Typhoon Mangkhut

September 18, 2018

GPM IMERG Adds Up Heavy Rainfall from Typhoon Mangkhut

In the past week, Typhoon Mangkhut has affected the Philippines, mainland China, and Hong Kong, as shown in this 7-day animation of NASA's satellite-based IMERG precipitation product. The upper frame shows the storm-total accumulation starting at 0100 UTC on September 11, 2018. Storm-total accumulations in excess of 4 inches stretched from Manila to the northern tip of Luzon Island where the rainfall triggered deadly landslides. The lower frame shows the short-term accumulation in a 3-hour period that slides from the beginning to the end of the 7-day-long movie. The sliding 3-hour accumulation clearly shows how Mangkhut's compact eyewall prior to its Philippines landfall was replaced by a much larger, ragged eyewall thereafter. In some cases, interactions with mountainous islands greatly reduce a tropical cyclone's rainfall, but in this case, Typhoon Mangkhut was too powerful to succumb to these mountain interactions.