Highest temperature in San Francisco on August 5?

Platform comparison

Market context

San Francisco International Airport’s top temperature on 5 August is a **range bet**, and the crowd is currently pricing the market as a split between the middle outcomes rather than a single runaway hot day: the two front-runners are **70–71°F** and **72–73°F**, both at **49% implied probability**, while the market as a whole is still assigning some weight to cooler mid-60s and low-70s finishes.[1] With the current crowd-implied probability at **0% YES** for any one bucket outside the leader set, the favourite/underdog read is straightforward: the consensus sits in the low 70s, while the value case comes from either a modest marine-layer cap keeping the high down, or a stronger-than-expected warm-up pushing the result into the higher bracket.

Historically, San Francisco August highs are usually modest by US standards, which helps explain why traders cluster around the low 70s rather than the 80s and above.[2][12][13] For context, the local climate reports and long-run August averages point to daytime maxima around the low 70s at most, and the airport station’s own historical record is the settlement source the market will use.[15][17] That makes the contrarian angle a classic Bay Area weather trade: if the marine layer hangs on, the under side of the consensus can pay; if inland heat bleeds farther west than expected, the higher band becomes the value spot.

The main catalyst to watch is the evolving Bay Area heat setup, because local forecasts have pointed to a broader California heat wave with Bay Area temperatures likely to spike from 5–8 August, while also noting that San Francisco is less exposed than interior locations because the marine layer remains a limiting factor.[16] For this market, the key dependency is not the regional heat headline but whether it reaches the airport station itself, as the final bucket depends on the highest observed reading there on the day, not the citywide forecast.[15][17] Traders should therefore focus on late-updated airport forecasts, marine-layer depth, and any shift in the warm inland gradient, since those are the variables most likely to move the result between the 70s bands.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to Who Will Win 2026, which mirrors the Polymarket order book directly.

Resolution & payout

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

FAQ

Where can I trade this market with the lowest fees?

Polymarket is geo-blocked in the US/UK/EU. The easiest 0%-fee broker into the same order book is Who Will Win 2026. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

Is this market available outside the US?

Polymarket itself is geo-blocked in the US/UK/EU. Always check the legal status of prediction markets in your jurisdiction before trading.

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.