Highest temperature in San Francisco on July 12?

Platform comparison

Market context

San Francisco’s July 12 high temperature is locked in the 67–79°F band by current forecasts, yet the market assigns 0% probability to any YES outcome, implying traders expect a resolution outside all listed ranges or a data anomaly. This stark disconnect suggests the crowd anticipates either a record-breaking heat spike above 79°F or a persistent marine layer keeping highs below 67°F, despite AccuWeather’s July 2026 model projecting daily highs consistently within that 67–79°F window for the airport station [1].

Historically, San Francisco International Airport rarely exceeds 79°F in July; the climate record since 1927 shows a maximum of 81°F in 2004, with typical July highs averaging 73°F [1][6]. The 0% implied probability aligns more closely with the coldest July days—such as July 7, which averaged 53.9°F lows—than with extreme heat events, suggesting traders may be pricing in an unusually cool marine influence rather than a heatwave [8].

Traders should monitor the National Weather Service’s daily climatological reports for KSFO, particularly the 2:55 PM maximum temperature reading, which determines the official daily high [6]. Any sudden shift in wind direction from the typical NW (300–310°) to southerly flows could trigger rapid warming, while sustained WNW winds at 12–20 mph typically reinforce the cool marine layer [3][4]. Watch for updates from Weather Underground’s KSFO history page, the market’s designated resolution source, as real-time station data may diverge from forecast models [2][9].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Highest temperature in San Francisco on July 12? 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.

Resolution & payout

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

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 Prediction Today. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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 Prediction Today trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

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.