Hong Kong records hottest day ever as Typhoon Dolphin fuels heatwave
Hong Kong logged 36.9C on Sunday, its highest official temperature since records began in 1884, as Typhoon Dolphin drove intense heat over the region before making landfall in Zhejiang.
Intelligence analysis by Llama
Hong Kong's observatory reported 36.9C, breaking a record held since 2017, with suburbs topping 39.8C. The outer bands of Typhoon Dolphin, which struck Zhejiang hours later, are blamed for the heat dome.
Hong Kong had its hottest day ever, like when you stand near an oven and the heat just won't stop. A big storm called Dolphin pushed hot air down on the city before the storm itself hit China's coast farther north.
Analysis
36.9C at the Observatory headquarters
The Hong Kong Observatory posted 36.9C on Sunday, edging past the previous mark of 36.6C set on 22 August 2017, just before Typhoon Hato struck. The 0.3C margin is small but symbolically large: the new high now anchors a record book stretching back to 1884, and the timing, on the eve of a typhoon landfall, mirrors the pattern that produced the 2017 benchmark. According to the observatory, "figures recorded at the observatory's headquarters are the official reference point for the city's records," meaning suburban readings are excluded from the headline number even though several stations across the territory ran hotter. The official framing matters because it is the figure that future heat waves will be measured against.
39.8C at Sheung Shui
Outside the headquarters, the urban heat island effect was stark. A weather station in Sheung Shui, in the city's northern New Territories, recorded 39.8C, which the observatory called "the highest temperature logged in Hong Kong since automatic weather stations were introduced in the 1980s." That distinction separates the long-running manual record from the denser, more modern network, but both benchmarks fell on the same day. The dual records make it harder to attribute the surge to local microclimate alone and strengthen the case that regional atmospheric conditions, not just city surfaces, drove the heat.
Yuhuan landfall and the subsidence mechanism
Dolphin came ashore near Yuhuan in Zhejiang province at about 5:30pm local time on Sunday, packing maximum sustained winds of 94 mph, equivalent to a category 1 hurricane on the Saffir-Simpson scale. The storm itself is roughly 1,000 km north-east of Hong Kong, yet the territory baked under its outer bands. The observatory explained that "its outer subsiding air will persistently bring extremely hot weather to the territory today to Tuesday," describing the classic typhoon-heat linkage in which descending air on the storm's periphery compresses and warms as it sinks. Mass flight cancellations and evacuations along China's east coast show that the heat event and the cyclone are not separate stories; they are two faces of the same weather system.
Key points
- Hong Kong's official temperature reached 36.9C on Sunday, the highest since records began in 1884.
- The previous record of 36.6C was set on 22 August 2017, also ahead of a typhoon landfall.
- A Sheung Shui station logged 39.8C, the highest reading since automatic stations were introduced in the 1980s.
- Typhoon Dolphin made landfall near Yuhuan in Zhejiang with 94 mph winds, equivalent to a category 1 hurricane.
- The observatory attributed the heat to outer subsiding air from Dolphin and warned of continued extreme temperatures into Tuesday.
The early "very hot weather warning" gave residents and employers time to adjust outdoor activity, and cooler, onshore flow is expected to arrive by Tuesday once Dolphin's outer subsidence weakens over the territory.
With Dolphin continuing to drive subsiding air through Tuesday, further records remain plausible, and the combination of typhoon disruption along the Zhejiang coast with extreme heat in Hong Kong raises short-term risks for outdoor workers, elderly residents, and aviation schedules.
