Hong Kong experienced its hottest October since records began, according to weekend data from the city's weather service.

The Hong Kong Observatory reported a monthly mean temperature of 27.6C on Sunday – a 0.2C increase from last year's already record-breaking figure for the same period.

Hong Kong began recording weather observations in 1884, according to the observatory.

This year's exceptionally strong El Nino has driven up temperatures around the world, with global forecasters warning for months that this would likely become the strongest ever observed.

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El Nino is the warming phase of a natural climate cycle, and temporarily raises sea temperatures in the tropical Pacific, triggering changes in weather that can increase the risk of drought and flooding, and exacerbate man-made global warming.

Hong Kong observed its highest temperature ever of 36.9C in August as Typhoon Dolphin swept warm air over the city.