Taipei: The Central Weather Administration (CWA) on Friday issued a heavy rain advisory for seven areas across Taiwan as a combination of southwesterly winds, a low-pressure system, and a weather front brought unstable weather conditions. The advisory covers Tainan, Kaohsiung, Pingtung County, and Taitung County in the south and Taoyuan, Hsinchu City, and Hsinchu County in the north, the CWA said. According to Focus Taiwan, the CWA defines heavy rain as accumulated precipitation of at least 80 millimeters within 24 hours or hourly rainfall exceeding 40 mm. The agency reported that heavy rain had already been recorded in mountainous areas of Pingtung, Kaohsiung, New Taipei, Taoyuan, and Hsinchu County earlier Friday morning. As of 10 a.m. Friday morning, 74.5 mm and 71.5 mm of rainfall had fallen in Pingtung County's Jiadong Township and Kaohsiung's Renwu District, respectively, since Thursday midnight, marking the highest recorded precipitation for the 10-hour period anywhere around Taiwan, according to CWA data. Independent meteorologist Wu Der-rong noted that moisture levels are expected to increase and atmospheric conditions are likely to remain unstable through Sunday. During this period, afternoon thunderstorms could still develop in some areas and may be accompanied by lightning, strong winds, and intense rainfall. Looking ahead, Wu indicated that the fifth plum rain front of the season is forecast to linger near Taiwan from June 8-14, while strengthening southwesterly winds move into the region. This combination is expected to usher in a more active phase of Taiwan's rainy season, increasing the likelihood of thunderstorms, strong winds, short-duration downpours, and potentially hazardous rainfall.