Lowest temperature in Hong Kong on August 10?

Platform comparison

Market context

Hong Kong’s overnight low on 10 August is the key number here, and the market’s **0% YES** implies the crowd is treating a very specific outcome as essentially impossible. For context, Hong Kong’s August climate normals put the mean minimum around **26.3°C to 27.0°C**, which means the settlement band is usually far above anything that would make a sub-20s reading likely[3]. That leaves the favourite with the “normal warm night” side of the book, while the underdog is any unusually cool dip driven by heavy rain, stronger winds, or an odd synoptic shift.

The comparable recent weather picture does not obviously support a shock lower print. Historical summaries for the past two weeks show lows mostly in the mid-to-high 20s Celsius, with the lowest recent reading at **76°F** on 31 July and the latest forecast products pointing to hot, humid conditions rather than a cool break[2][4][12]. August climatology is also stubbornly warm: even in wetter years, Hong Kong’s monthly mean minimum has tended to sit around the upper-20s, not near the lower ranges that would matter for a contrarian YES case[9][11]. On that framing, the consensus looks rationally anchored to the warmer temperature bands, with only a small tail for an outlier cool morning.

The main catalyst is the Hong Kong Observatory’s final “Daily Extract”, because the market cannot resolve until the **Absolute Daily Min (deg. C)** for 10 August is published on the climate pages[1]. Traders should watch whether the Observatory posts the extract on schedule and whether any late-day showers, cloud cover, or easterly flow trim the overnight minimum; the day-ahead forecast also points to **partly cloudy and very warm** conditions, which leans against a surprise low[12]. The value spot, if any, is usually in the smallest adjacent temperature band that still reflects a plausible one-decimal read, rather than betting on a true cold outlier.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Lowest temperature in Hong Kong on August 10? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

Resolution & payout

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