Rainstorms with strong winds are expected to batter northern China and the Yellow River region of central China on Monday, and Beijing could be hit by the heaviest rainfall since its flooding season began in June, meteorological services said.

The National Meteorological Center renewed on Sunday its orange alert, the second-highest of the four-tier system, for rainstorms across the country. In China's four-tier weather warning system, red represents the most severe, followed by orange, yellow and blue.

The center warned that through Monday afternoon, some parts of Shanxi, Hebei, Shandong and Henan provinces will experience downpours and high winds.

It advised local authorities to be on the alert for possible flooding, landslides and mudslides, and suggested halting outdoor activities in hazardous areas.

Rainfall is expected in Beijing through Wednesday, with a large amount of precipitation and strong winds, the Beijing Meteorological Service said. Hail could hit some mountainous areas of the city, according to the service.

The State Flood Control and Drought Relief Headquarters has sent three work groups to Shanxi and Hebei provinces and Beijing to assist with disaster prevention.

The Ministry of Water Resources said it would pay high attention to flood prevention in the Haihe River region of northern China－including the Beijing-Tianjin-Hebei region, Liaoning, Henan, Shandong and Shanxi provinces, and the Inner Mongolia autonomous region－where flash floods could occur due to heavy rain. The ministry warned local authorities to prepare for worst-situation flooding.

Since June 1, the capital has had about 50 percent more rain than normal, the Beijing Meteorological Service said, warning that people need to be aware of low visibility on roads.

Due to the persistent wet days, soil has become moist and people should also be aware of mountain torrents, the service said.

The approaching storm triggered a yellow alert from the service on Sunday.

The city's precipitation was expected to reach 60 to 100 millimeters by 8 am on Tuesday, the service said.

All sightseeing areas in Beijing's mountain districts were closed to the public starting on Sunday at noon, and homestays stopped receiving guests.

Major parks in the capital have been temporarily closed and will reopen when conditions permit. To be prepared for heavy downpours, authorities have been inspecting pump stations and putting staff members on standby for possible emergencies.

Heavy downpours that have lashed seven cities in Southwest China's Sichuan province since Friday have pushed up water levels in 14 rivers. More than 580,000 people have been affected by the flooding of rivers, with local authorities relocating over 109,000 residents.

Floodwaters have inundated 4,578 hectares of crops and damaged 426 houses in the affected areas. Many sections of road were disrupted due to landslides.

Dazhou, a city in Sichuan, activated the highest alert for rainstorms on Sunday morning, as two major rivers passing the city were in danger of flooding.

Meanwhile, in southern China, the Yangtze and Huaihe river regions braced for the summer's hottest, most sultry days, which began on Sunday and could last for 40 days. The National Meteorological Center issued an alert for high daytime temperatures.

Zhang Juan, an analyst at the China Meteorological Administration, said that from Sunday to July 20, these areas will experience temperatures above 35 C, while in northern China, rain and heat will alternately appear.

"It will be like sauna days in Anhui, Hunan and Zhejiang provinces," she said.

Xinhua contributed to this story.