The Hong Kong Observatory has issued the No 1 storm warning signal as Severe Typhoon Podul approaches, bringing very hot weather to the city ahead of heavy downpours and disrupting flights.

The weather forecaster raised the signal at 8.40am on Wednesday and said that it would assess the need to issue higher warnings later in the day or early Thursday.

“Under the influence of the outer subsiding air of Podul, it will be very hot during the day over Guangdong and heat-triggered showers will also affect the region later [on Wednesday],” it said.

“With Podul making landfall over the vicinity of eastern Guangdong to southern Fujian [on Thursday], its associated rain band will be rather close to the coast of Guangdong.”

The city is expected to experience heavy and squally showers, thunderstorms and swells by then, according to the Observatory. Podul means “willow tree” in Korean.