BEIJING, June 21 -- China's meteorological authority on Friday issued a blue alert for severe convective weather in vast parts of the country.

From Friday morning to Saturday morning, thunderstorms, gales and hail will sweep parts of Inner Mongolia, Heilongjiang, Jilin, Liaoning, Hebei, Beijing, Tianjin, Henan, Anhui, Jiangsu, Hubei, Hunan, and Guizhou, with the maximum wind force reaching 17.2 to 28.4 meters per second, according to the National Meteorological Center.

Short-term heavy rainfall with hourly precipitation ranging from 20 mm to over 50 mm will lash parts of Inner Mongolia, Heilongjiang, Jilin, Liaoning, Hebei, Beijing, Tianjin, Henan, Anhui, Jiangsu, Shanghai, Hubei, Hunan, Zhejiang, Chongqing, and Guizhou, the meteorological center said.

It has advised the public to take precautions against heavy rain, thunder and gales, and has recommended reducing outdoor activities.

Vessels operating in or transiting affected waters should return to port or take detours, according to the center.

China has a three-tier, color-coded weather warning system for severe convective weather, with orange representing the most severe warning, followed by yellow and blue.