Trough of low pressure over northern part of southern China set to develop into cold front on Wednesday, crossing coastal areas by next day
2-MIN READ2-MIN ListenOscar LiuPublished: 6:21pm, 21 Apr 2026This story has been made freely available as a public service to our readers. Please consider supporting SCMP’s journalism by subscribing.Hong Kong will face squally thunderstorms and a nine-degree plunge in temperature later this week as a cold front sweeps across the South China coast, with the mercury expected to dip to 21 degrees Celsius (69.8 Fahrenheit) on Friday, the city’s forecaster has said.
The Observatory said on Tuesday that the city would first experience unseasonably hot weather the next day due to a southerly airstream, with temperatures in urban areas expected to climb to 30 degrees.
However, a trough of low pressure over the northern part of southern China was forecast to “develop into a cold front” on Wednesday, crossing the coastal areas by the next day, the forecaster added.
“Under the influence of the associated northeast monsoon, temperatures over Guangdong will fall in the latter part of this week. Meanwhile, under the influence of upper-air disturbances, the weather will be unsettled with showers and thunderstorms over the region,” it said.
According to the nine-day weather forecast, temperatures in the urban areas will peak at 30 degrees on Wednesday before the cold front triggers a dramatic slide.
