Typhoon Prapiroon formed in the western Pacific on July 31, 2006, off the coast of Luzon, the northernmost of the Philippine Islands. The tropical depression strengthened to storm status in the next day after crossing Luzon, and reached typhoon status by early August 2, as it continued east-northeast across the South China Sea towards the Asian mainland. The storm system was blamed for some six deaths in the Philippines as it crossed the island. As of August 3, it was predicted to make landfall in southern China not far from Hainan Island, packing forecasted winds around 115 kilometers per hour (73 miles per hour). Fishing boats were ordered into port, and rescue teams were being prepared for possible flooding and landslides.

This photo-like image was acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Aqua satellite on August 2, 2006, at 1:50 p.m. local time (05:50 UTC). Prapiroon had a very well-defined spiral shape and active thunderstorm systems (bright, puffy clouds) close to the eyewall. Prapiroon at the time the Aqua satellite passed overhead had a partially opened eye: the center of the storm still had some light cloud cover. Sustained winds in the storm system were estimated to be around 120 kilometers per hour (75 miles per hour) around the time the image was captured, according to the University of Hawaii’s Tropical Storm Information Center.