https://phys.org/news/2018-08-nasa-gpm-john-rainfall-eastern.html

The GPM satellite's radar data (DPR Ku Band) were used to show the 3-D structure of rainfall in tropical storm John. The Dual-Frequency Precipitation Radar (DPR) is one of the main instruments on the GPM Core Observatory satellite. The DPR Ku Band(13.6 GHz) radar is an updated version of the radar that flew on the TRMM satellite from 1997 to 2015.

GPM's radar showed that storm tops were tall in a feeder band on JOHN's eastern side but the tallest tower was measured in storms just north of JOHN's center of circulation. GPM's DPR found that the tall storms north of JOHN's center were reaching heights above 13.7 km (8.5 miles). GPM is a joint mission between NASA and the Japan Aerospace Exploration Agency, JAXA.