https://phys.org/news/2018-06-nasa-small-strength-newly-tropical.html

At 9:55 a.m. EDT (1355 UTC) on May 19, the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA's Terra satellite gathered infrared data on 08W as it approached Taiwan's southwestern coast. Infrared data provides temperature information. MODIS revealed a few very powerful thunderstorms around the center where cloud top temperatures were as cold as minus 80 degrees Fahrenheit (minus 62.2 Celsius). NASA research has shown that cloud tops with temperatures that cold were high in the troposphere and have the ability to generate heavy rain.

The Central Weather Bureau of Taiwan issued an Extremely Heavy Rain Advisory is in effect from tonight, June 14, through Friday morning June 15 for Tainan City, Kaohsiung City, Pingtung County, Hengchun Peninsula, Taitung County, Lanyu and Ludao Islands.