BEIJING, July 25 (Xinhua) -- China's national weather observatory continued its blue alert for rainstorms on Tuesday, as heavy rain is expected in parts of north China and some areas in the south over the next 24 hours.

From Tuesday to Wednesday, heavy rain is expected in parts of Inner Mongolia, Shanxi, Hebei and Hainan, according to the National Meteorological Center (NMC).

Precipitation will reach up to 150 millimeters in some regions, and some of these areas may see thunderstorms and gales, said the NMC.

The center warned local authorities to reduce outdoor activities and take precautions against strong winds, flooding and geological disasters.

China has a four-tier color-coded weather warning system, with red the most severe, followed by orange, yellow and blue.