BEIJING - The city is about to witness its longest period of continuous rain for at least four years, weather experts said.

Beijing Meteorological Bureau issued a yellow alert on Monday morning, the third highest level in its four-color storm warning system and predicted storms will continue to hit the capital this week.

"The possibility of rainstorms covering the whole city is quite small, though," said Sun Jisong, the bureau's chief engineer.

According to the bureau, a cold front from the Inner Mongolia autonomous region and southern parts of Hebei province that is circling the city is the cause of the frequent rainstorms.

"Residents think the rainfall this year has been larger than before, but in fact the rainfall in July has been lower than average for this period," Sun said.

Precipitation in the first 17 days of this month was about 60 millimeters, 25 percent below average, he added.

"This is Beijing's rainy season. It's not strange to have rainy days. In 1996 it rained for 11 consecutive days," he said.

On July 15 Xinglong community in Chaoyang district became the first residential complex in Beijing to set up its own weather warning system.

Using an automatic weather station, managers can now inform residents about coming gales and storms using the LED panels in public areas and text messages. Schools will receive alarms two hours before a rainstorm hits.

After a one-year pilot program the authorities plan to roll our the system in other areas.