Northern China is expected to experience several days of hot and sunny weather from Monday to Thursday, with many places likely to see their first high-temperature day of the year, while southern China braces for a new round of heavy rain and severe convective weather, China Central Television reported on Monday.

Under the influence of a strong high-pressure system, temperatures continued rising across northern China on Sunday, with temperatures in Beijing, Tianjin, Hebei and other northern regions exceeding 30 C, while some places recorded temperatures above 35 C, the report noted.

According to Weather China's report on Sunday, heat across regions along and north of the middle and lower reaches of the Yangtze River is expected to intensify further from Monday to Wednesday, with temperatures continuing to climb steadily. Cities including Hohhot, Xi'an and Nanjing could see highs reach 33 C to 34 C.

A high-pressure system brings sinking air that becomes warmer and drier as it moves downward. Combined with clear skies and strong sunshine, this allows the ground to heat up quickly and causes temperatures to rise rapidly, Ma Jun, director of the Institute of Public and Environmental Affairs, told the Global Times on Monday.

The unusually early heat this year is also linked to the broader trend of global warming, which has made early-summer high-temperature days arrive increasingly earlier in recent years, Ma said.

While northern China is being "baked" by heatwaves, southern China is expected to be soaked by a new round of rainfall starting Monday. According to Weather China, the heaviest rain is expected from Tuesday to Wednesday, as strong warm and moist air brings heavy to torrential rain to parts of central Jiangnan, southern Jiangnan and northern South China, with some areas likely to see extremely heavy rainfall.

From Monday to Thursday, parts of Jiangnan, South China, eastern Guizhou and southern Hubei will not only see heavy rainfall, but also severe convective weather including thunderstorms, strong winds and hail, according to the China Meteorological Administration.

Ma noted that the south's typical humid heat usually becomes more noticeable in July, and temperatures there are likely to surpass those in the north later in the summer.

Rising temperatures and strong sunshine in parts of northern China could lead to higher ozone levels and photochemical smog in the coming days, especially from afternoon to early evening, Ma said. He suggested against outdoor exercise during those hours and recommended engaging in such activities in the morning or evening.