GPM passes directly over Tropical Storm John off the coast of Mexico

NASA's Global Precipitation Measurement mission or GPM core observatory satellite flew over Tropical Storm John on August 6, 2018.   GPM showed that the large tropical cyclone was becoming well organized and had intense rainfall within feeder bands that were spiraling toward John's center. GPM's radar (DPR Ku Band) revealed that a band of powerful storms northeast of John's center were dropping rain at a rate of close to 160 mm (6.3 inches) per hour.

The GPM Core Observatory carries two instruments that show the location and intensity of rain and snow, which defines a crucial part of the storm structure – and how it will behave. The GPM Microwave Imager sees through the tops of clouds to observe how much and where precipitation occurs, and the Dual-frequency Precipitation Radar observes precise details of precipitation in 3-dimensions.

GPM data is part of the toolbox of satellite data used by forecasters and scientists to understand how storms behave. GPM is a joint mission between NASA and the Japan Aerospace Exploration Agency. Current and future data sets are available with free registration to users from  NASA Goddard's Precipitation Processing Center website.

GPM passed over Tropical Storm John on August 6, 2018. As the camera moves in on the storm, DPR's volumetric view of the storm is revealed. A slicing plane moves across the volume to display precipitation rates throughout the storm. Shades of green to red represent liquid precipitation extending down to the ground. Frozen precipitation is displayed in cyan and purple.

Visualizers: Kel Elkins (lead), Greg Shirah

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