The heaviest rainfall so far this year began hitting areas in North China on Thursday, bringing some relief to a region that has been scorched in recent weeks by persistently high temperatures, the National Meteorological Center said.

From Thursday evening through Sunday, rainfall will occur in North and Northeast China and in the Yellow and Huaihe rivers region. Most of the rainfall will hit the Beijing-Tianjin-Hebei province area, the center said.

"For North China, this will be the strongest rainfall of the year," said Wang Weiyue, a weather analyst from the China Meteorological Administration.

The rain will spread from west to east, covering more than 10 provinces. The heaviest will occur on Friday in Beijing and Hebei, Wang said.

The downpours will help lower temperatures in a region that has been besieged by relentless heat, which has had an adverse effect on people in the area. For example, hot weather was determined to be the cause of death of a tour guide in Beijing on July 2.

On Wednesday, the Beijing South Suburban Observatory recorded a high temperature of 37.1 C, making it the 28th high-temperature day this summer, surpassing the previous record of 26 days in 2000. In meteorological terms, a high-temperature day refers to a day with a maximum temperature of 35 C or above.

Wang said that the constant heat in North China has created unstable atmospheric conditions, triggering strong convective weather and intense short-term rainfall.

This weekend's wet weather comes on the cusp of North China's rainy season, which generally begins in late July or early August, Wang said.

Following this round of heavy rainfall, another round is expected to begin in North China and the Sichuan Basin in the southwest on or around Tuesday.

The Ministry of Water Resources has initiated a level IV emergency response, the lowest for water and drought disasters in the Beijing-Tianjin-Hebei area.

The ministry said that water levels in some of the northern rivers may experience flooding above the warning level as a result of this weekend's heavy rainfall.

The ministry has sent working groups to assist in efforts to prepare for the downpours. The Haihe River Water Conservancy Commission and some provincial water resource departments have been notified to monitor the weather and water level changes to ensure the safety of water engineering operations and flood prevention in small and medium-sized rivers and mountainous areas.