Highest temperature in San Francisco on August 10?

Platform comparison

Market context

San Francisco International Airport finished 10 August with a modest warm-up rather than a heat spike, and the latest public histories show the day topping out around the low 70s Fahrenheit rather than anywhere near the mid- or upper-70s. Weather Underground’s daily history page is the settlement source here, and the broader historical record for SFO in August puts 70s as normal, with the site’s climate report showing a 73°F normal maximum for 10 August and a record high of 87°F.[2][6]

That makes the market’s 0% implied “yes” on any higher temperature band easier to read: the conditional path to an upside surprise was always narrow unless a late-afternoon burst overperformed. Comparable August days at SFO often cluster in the high 60s to low 70s, and the recent historical pages show no sign of the sort of sustained inland push that would typically lift the airport into a much hotter range.[1][4][11] In other words, the market is being priced against the airport’s usual maritime moderation, not a deep-summer extreme.[6][14]

What traders should watch now is any late-morning or afternoon observation sequence in the Weather Underground daily table, because the market resolves to the highest value recorded there, not the summary “Day High & Low” line.[2][12] The key dependencies are the airport’s official observation cadence, whether a later update revises the day’s peak, and any local marine-layer clearing that can briefly lift temperatures before the sea breeze returns; the National Weather Service’s SFO observations and nearby forecast pages are useful cross-checks for intraday context, but the final print is the Wunderground daily record.[9][13]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Highest temperature in San Francisco on August 10? across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to Prediction Today, which mirrors the Polymarket order book at 0% fees.

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