https://phys.org/news/2018-08-nasa-gpm-tropical-storm-hector.html

At that time GPM passed overhead, Hector's maximum sustained winds were estimated to be about 30 knots (34.5 mph). Powerful convective storms were wrapping around the western side of the deepening tropical low's center of circulation. GPM's Dual-Frequency Precipitation Radar (DPR) instrument collected data showing that rain in some of these storms was falling at a rate of almost 198 mm (7.8 inches) per hour.

At NASA's Goddard Space Flight Center in Greenbelt, Maryland, the GPM satellite's radar data (DPR Ku Band) were used to create a 3-D structure of precipitation within the forming tropical storm. This cross-section view, looking toward the northwest, showed that powerful convective storms to the west of the forming tropical storm's center of circulation contained very intense downpours. Radar echoes measuring over 57dBZ were returned to the satellite. Storm tops in that area were found by GPM to reach heights above 12 km (7.4 miles).