BEIJING, July 17 (Reuters) - Typhoon Talim became the first typhoon to make landfall in China this year on Monday evening, prompting authorities to issue flood warnings, cancel flights and trains, and order people to stay at home.

Talim, the fourth typhoon of the year, made landfall at 10:20 p.m. (1420 GMT) in Zhanjiang city of Guangdong province, with winds near its centre clocked at a top speed of 136.8 kph (85 mph), according to Guangdong weather bureau.

Winds stronger than 150 kph would put Talim in the severe typhoon category, very rare for a typhoon this early in the rainy season.

Talim is expected to move at a speed of 20 km per hour northwest and into Guangxi region early on July 18, Guangdong weather bureau added.

The national forecaster has urged authorities in Guangdong and Hainan to be on standby to respond to the typhoon.

Markets in Hong Kong halted trade for the day as the city's observatory put up a storm signal for Talim, and all court hearings in the city were adjourned.

China's meteorological centre forecast gale force winds in seas near southern provinces and regions and exceptionally heavy rains of 250-280 mm (9.8-11 inches) on the southwestern coast of Guangxi and northern Hainan Island.

Parts of Guangxi were told to brace for flash floods through Tuesday.

"Violent" waves of 6 to 9 m (20 to 30 feet) are expected to assail northern parts of the South China Sea through Tuesday, according to state media.

Hainan's Marine Forecasting Station warned of waves of up of 6 m south of the tourist island, Xinhua reported.

Authorities in Hainan asked ships in nearby waters to return to port and ferry services between Hainan and Guangdong were suspended early on Sunday.