Highest temperature in Hong Kong on August 21?

Platform comparison

Market context

Hong Kong’s high for 21 August will be set by the Hong Kong Observatory’s final “Absolute Daily Max” reading, with settlement only once the Daily Extract is published. The market is already marked at 0% YES, and the practical question is whether the day finishes in the relevant temperature band rather than whether the figure prints at all.

That zero sits against a late-summer baseline that usually favours a high reading in the low- to mid-30s Celsius, but not necessarily an outlier. AccuWeather’s monthly outlook showed Hong Kong running with daily highs around 87–94°F, while the Observatory’s own recent forecasts have been consistent with hot conditions earlier in the month, including maxima of about 33–35°C and warnings that temperatures in some areas could reach 37°C or above[2][3][4]. Recent coverage also noted the city’s hottest official day on record at 36.9°C, underlining how quickly extreme readings can emerge when regional heat builds[7][8].

For traders, the key catalyst is the Observatory’s intraday forecast path: cloud, showers and onshore flow can cap the day’s maximum, while clear spells and subsidence can push it higher. On the morning of 21 August, the Observatory reported 27°C at 8 a.m., light rain, and only low UV intensity, which is less supportive of a sharp midday surge than a dry, sunny start[1]. Cross-platformly, the contract looks more conservative than recent heat headlines suggest, with prediction-market pricing far below the kind of elevated temperature risk implied by the Observatory’s earlier August warnings and the broader media consensus around persistent hot weather[4][7][9].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

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