Fishing vessels are moored at a fishing port in Taizhou, Zhejiang province, on Tuesday. As Typhoon Dolphin approaches, more than 3,000 fishing vessels across Taizhou have returned to port as local authorities implement comprehensive typhoon preparedness measures. SUN JINBIAO/FOR CHINA DAILY

A powerful typhoon churning across the western Pacific Ocean could threaten China's eastern coastline later this week, as meteorologists warned that August is likely to bring an active tropical cyclone season.

Typhoon Dolphin, this year's 13th named storm, is moving westward at 20 to 25 kilometers per hour and is not expected to affect China's coastal waters until Thursday, according to the China Meteorological Administration.

Jia Xiaolong, deputy director of the National Climate Center, said the typhoon could make landfall around Sunday between the Yangtze River estuary and Zhejiang province, bringing strong winds and heavy rain to Shanghai and the provinces of Zhejiang, Jiangxi and Anhui.

An alternative scenario would see the storm turn northward offshore on Aug 10 or 11 before making landfall, or brushing the coast, between the Yangtze River estuary and the Shandong Peninsula, potentially affecting Shanghai and the provinces of Jiangsu, Anhui, Shandong and Liaoning.

"The track will be highly uncertain after the typhoon moves into the East China Sea," Jia said, adding that the National Meteorological Center will continue issuing updated forecasts and warnings as the storm develops.

Meteorologists said July saw above-average tropical cyclone activity.

Five tropical cyclones formed over the western North Pacific and the South China Sea during the month, and three made landfall in China, both exceeding the historical average for July, Jia said.

The active pattern is expected to continue in August, said Xiao Chan, deputy director of the National Meteorological Center.

Six to seven tropical cyclones are forecast to develop over the western North Pacific and the South China Sea this month, above the long-term average of 5.6. Of those, two to three are expected to make landfall in China or significantly affect the country, close to the seasonal norm, he said.

A tourist cools off in the mist from a dragon-shaped misting installation on a street in Shanghai on Monday as scorching heat grips many parts of the country. TANG YANJUN/CHINA NEWS SERVICE

Forecasters also expect one or two relatively strong typhoons to move northward into North and Northeast China, where they could trigger widespread flooding even after weakening.

"As northward-moving typhoons interact with cold air and their outer rain bands expand, they can produce extreme rainfall over large areas," Xiao said.

Such storms can bring multiple hazards, including urban inundation, river flooding, landslides and, in isolated cases, tornadoes and severe thunderstorms.

Meteorologists urged local governments to strengthen maritime safety measures, evacuate offshore workers when necessary, reinforce coastal infrastructure, improve urban drainage and prepare evacuation plans for landslide-prone communities.

Meanwhile, much of China is expected to experience above-average temperatures this month.

Most regions are forecast to see higher-than-normal temperatures and more frequent hot days in August, with an elevated risk of heat waves across much of the country.

Over the next 10 days, persistent heat is expected across Northwest China. Temperatures in Turpan, Xinjiang Uygur autonomous region, could reach 40 to 45 C.

From Tuesday to Friday, temperatures of 35 to 37 C are forecast across parts of Northeast China, with isolated areas reaching 38 to 40 C. Parts of Liaoning, Jilin and Shandong provinces could approach or break historical temperature records.

Meteorologists warned that high humidity across eastern and central China will make conditions feel significantly hotter, while residents in Xinjiang will face intense sunshine and dry heat.

The public is advised to avoid strenuous outdoor activities during the hottest part of the day, stay hydrated, use air conditioning where available and pay particular attention to vulnerable groups.