Highest temperature in San Francisco on July 12?

Platform comparison

Market context

San Francisco’s July 12 high temperature is the real-world event determining this market, with the settlement tied to the San Francisco International Airport Station reading from Wunderground. The crowd currently assigns a 0% probability to the YES outcome, implying near-total consensus that the temperature will fall outside the specified range. This extreme pricing suggests traders view the range as implausibly high or low relative to historical norms for mid-July in the city.

Historically, San Francisco’s July highs average around 70°F, rarely dipping below 64°F or exceeding 79°F, though extreme outliers have occurred, including a record 106°F in September 2017 and 103°F in June 2000 [1][2]. Notably, July 12, 2021, saw a record-low maximum of just 57°F, tied with readings from 1899, 1901, and 1912 [9]. These cases frame the current 0% probability: if the range is set above 79°F, the crowd is likely correct; if it includes 57–64°F, there may be contrarian value given the historical volatility and the 2021 anomaly.

Traders should monitor the National Weather Service Bay Area forecasts for heat dome developments or marine layer persistence, as these directly dictate whether temperatures breach typical July ceilings [7]. While no specific announcements are scheduled for July 12, 2026, the dependency on marine air intrusion remains the primary catalyst; a sudden shift in wind patterns could trigger an underdog spike. Recent data shows the highest temperature in late June 2026 was 72.6°F, with a low of 54.3°F on July 11, 2026, indicating active thermal variability [5].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in San Francisco on July 12? 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

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

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. 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.

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 fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Who Will Win trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.