Tea farmer Xiang Xuejun has been growing Longjing tea, a variety of green tea, for three decades on his mountainside tea fields in Zhejiang province.

But since early July, when scorching temperatures brought a severe drought to southern China, the 65-year-old has had to carry water up the fields after his water source that fed irrigation pipes dried up.

"Never before have I experienced such a severe drought," he said.

Xiang, like millions of farmers in the nation's southern regions, are growing increasingly concerned about this year's harvest. And with the heat wave likely to continue until mid-August, according to the China Meteorological Administration, relief won't be coming any time soon.

According to the State Flood Control and Drought Relief Headquarters, as of Sunday, 3.5 million hectares of farmland have taken a beating from the drought, with nearly 6 million people suffering from a shortage of drinking water.

Seven of China's top 10 hottest cities on Monday were in Zhejiang, with temperatures upward of 40 C, according to the National Meteorological Center.

At least 13 provinces and regions are affected by the drought, authorities said. Hunan, Guizhou and Hubei provinces and Chongqing are facing the most severe droughts.

The State Council has allocated 1.7 billion yuan ($267 million) to help regions with drought relief.

Hunan raised its drought emergency warning from its third highest alert to its second, while 41 of 77 rivers passing through the province have dried up in the prolonged drought.

Meteorological agencies use a four-tier, color-coded weather warning system, with red being the most severe, followed by orange, yellow and blue.

As of Monday, Changsha, the provincial capital, experienced 45 days of temperatures above 35 C since June, more than any other city, according to the National Meteorological Center. The center has issued an orange heat alert for the region and warned that temperatures in Zhejiang and Fujian provinces may reach 41 C on Tuesday.

In Chongqing, the prolonged heat has been so unbearable and public swimming pools so crowded for 58-year-old Han Zijing, who has been swimming every day for the past twenty years, that she's going to take up another sport for the summer.

Han lives on a university campus and usually swims at the school's pool, which changed its closing time from 7:30 pm to 9 pm on July 1 to cope with the huge crush of swimmers.

The extended hours have not made it easier to find room to swim, Han said.

"Even in July, during the summer vacation, when most students go home, there are still too many people in the pool to swim."

She will return to the pool in September, when "hopefully the pool won't be so popular", she added.

In Fuzhou, capital of Fujian province, where authorities issued a red alert on Monday, demand for power is increasing, putting enormous pressure on electricity suppliers.

Chen Yang, an official with the State Grid's Fuzhou branch office, said people should avoid using power at peak times.

Dozens of people have died of heat stroke in Shanghai since early July. Temperatures have risen to 39 C and above in recent days.

Shanghai's meteorological bureau said the city will see a new heat wave this week, with temperatures expected again to exceed 39 C between Tuesday and Thursday.

Among the effects of the scorching summer heat has been a rise in demand for ambulances. "Ambulances are being dispatched 1,000 times a day, while on extremely hot days it's more than 1,100 times," said Zhang Yu at Shanghai Medical Emergency Center.

Wang Hongyi in Shanghai, Wen Xinzheng in Changsha, and Sun Li in Fuzhou contributed to this story.