Taipei: Heavy rain is expected to continue across much of Taiwan through Tuesday morning, with torrential rainfall likely in southern and southeastern areas, due to strong southwesterly winds and multiple weather systems in the area, the Central Weather Administration (CWA) said Monday.

According to Focus Taiwan, the CWA issued a warning Monday for torrential or extremely torrential rain in Tainan, Kaohsiung, Pingtung, and Taitung, and for extremely heavy to torrential rain in Chiayi, Hualien, and on the Hengchun Peninsula.

Heavy to extremely heavy rain is also expected Monday through Tuesday in Changhua, Yunlin, Chiayi City, Yilan, Green Island, Penghu County, and mountainous areas of Taichung and Nantou, the CWA said.

The CWA also warned of lightning, strong wind gusts, and flooding in low-lying areas, as well as landslides, rockfalls, debris flows, and rapidly rising rivers in mountainous regions this week.

Meanwhile, as Typhoon Saudel continues to move toward Taiwan, a sea warning may be issued on Wednesday, CWA forecaster Yeh Chih-chun said at a press briefing on Monday.

Yeh said Saudel is expected to approach the Ryukyu Islands on Wednesday before turning southwestward and passing close to Taiwan on Thursday and Friday. As the typhoon draws near, increasing rainfall can be expected in northern Taiwan, he said, adding that it is still unclear how close Saudel will pass.

Although Saudel is expected to start weakening gradually on Tuesday, it will approach Taiwan as a typhoon, Yeh said. Another tropical storm, named Atsani, which formed southeast of the Philippines at 8 a.m. Monday, is expected to be absorbed into Saudel's circulation, he said.

A third storm, Narra, located near Vietnam on Monday, is not expected to directly affect Taiwan, Yeh said. On Monday, sea conditions around Taiwan remained hazardous due to the weather systems, which are kicking up rough waves and pushing sustained winds of 63-103 kilometers per hour, the CWA said.