A relatively warm and dry April
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With the prevalence of a fresh to strong easterly airstream, the weather of Hong Kong was mainly cloudy with a few showers and rather low visibility in some areas on the first three days of the month. Affected by upper air disturbances, there were also a few isolated thunderstorms on April 2. The easterly airstream affecting the coast of Guangdong was replaced by a warm and humid southerly airstream on April 4. Locally, the weather remained mainly cloudy with a few showers and rather low visibility in some areas on April 4 to 6.
Meanwhile, a cold front moved across the coast of Guangdong on the night of April 6 and brought some rain to the territory. The weather of Hong Kong became cooler with sunny intervals during the day on April 7. Under the influence of a northeast monsoon, it was mainly cloudy with bright periods during the day on the next three days. There were also a few rain patches on the morning of April 9. Under the rain, temperatures at the Observatory dropped to a minimum of 18.0 degrees that morning, the lowest of the month. With the moderation of the northeast monsoon and under light wind conditions, apart from some coastal mist in the morning, the weather was generally fine and hot during the day on April 11 and 12.
While the easterlies picked up slightly, the weather of Hong Kong remained generally fine on April 13. With the easterly flow abating and under the influence of a cloud band, the weather became cloudier with a few light rain patches and relatively low visibility in some areas at first on April 14. Affected by a weak continental airstream, local weather turned sunnier and hot during the day on April 15 to 17. There was also some haze on April 15. With plenty of sunshine, temperatures at the Observatory rose to a maximum of 30.8 degrees on the afternoon of April 16, the highest of the month.
Under the influence of a southerly airstream, apart from a few showers and mist patches, it was hot with sunny intervals during the day on April 18. Affected by a trough of low pressure, the weather of Hong Kong became unsettled with occasional showers and squally thunderstorms on April 19 to 21. A band of intense squally thunderstorms associated with a trough of low pressure brought violent gusts to many places on the morning of April 19. Gusts of around 100 kilometres per hour were once recorded at Star Ferry. A row of hoardings in Sha Tin collapsed that morning with six persons injured. Moreover, hail was reported at Yuen Long and Fanling during the passage of the intense thunderstorms in the small hours of April 21. On these three days, more than 30 millimetres of rainfall were recorded generally over Hong Kong and rainfall even exceeded 70 millimetres over the southern part of the territory.
Under the influence of a fresh to strong easterly airstream and a subsequent trough of low pressure over Guangdong, it was mainly cloudy with a few showers, and the visibility was rather low in some areas on April 22 to 24. With the arrival of the northeast monsoon, the weather became slightly cooler with a few rain and mist patches on April 25. While it remained cooler in the morning, the weather turned brighter and dry during the day on April 26. Affected by the northeast monsoon, apart from a few rain patches, it was mainly cloudy with sunny intervals during this day the next day. With the moderation of the northeast monsoon, while it was mainly cloudy with a few rain patches at first, the weather became fine during the day on April 28. Under the influence of a trough of low pressure over inland Guangdong, local weather turned cloudier with a few showers on April 29. A trough of low pressure then developed into a cold front and moved across the coastal areas of Guangdong that night. Affected by the associated northeast monsoon, it was dry with sunny periods during the day on the last day of the month.
Two tropical cyclones occurred over the South China Sea and the western North Pacific in April 2023.
Details of issuance and cancellation of various warnings/signals in the month are summarised in Table 1. Monthly meteorological figures and departures from normal for April are tabulated in Table 2.
Ends/Wednesday, May 3, 2023
Issued at HKT 15:00
Issued at HKT 15:00
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