SHANGHAI (AP) -- Unusually cold weather has caused shortfalls of power and natural gas in Shanghai and parts of central China, local government reports said Wednesday.

The surge in energy consumption due to the cold snap, which began last week, is typical of the challenges the country is facing as it struggles to meet demand from consumers whose growing earning power enables them to adopt more modern lifestyles.

Shanghai, a city of about 20 million, was facing a record potential shortage of 1.9 million kilowatts after the sudden surge in demand caused four local power plants to malfunction, the city government said in a notice on its Web site.

It alerted city residents of potential outages.

Homes in areas south of China's Yangtze river are traditionally unheated, though many now have air conditioners installed both for cooling and heating. The sudden drops in temperature apparently prompted families to turn their heaters on.

Temperatures in Shanghai dipped close to freezing Tuesday and were forecast to remain unseasonably low for at least several days. But cities across central and southern China were hardest hit by the cold snap and, in some regions, unusually heavy snow.

Wuhan, a city in the middle reaches of the Yangtze river, said it suspended natural gas services to dozens of businesses and gas stations to help ensure supplies for residential customers after it suffered what local media said was its worst snowstorm in 40 years.

In the past five days, daily demand jumped by 50 percent from its usual level, to 210 million cubic meters, the city said in a notice on its Web site. It blamed the surge in demand on increasingly popular gas-powered home water heaters.

The company that runs most of China's vast power distribution network, State Grid of China Corp., reported power shortages in several other provincial cities.

Authorities had vowed to prevent such disruptions after severe winter storms that ripped down power lines and damaged equipment two years ago, causing billions of dollars in losses both to power providers and to businesses forced to shut down due to outages.