Highest temperature in San Francisco on July 13?

Platform comparison

Market context

San Francisco International Airport is forecast to reach highs between 67°F and 79°F on 13 July 2026, making a record-breaking spike unlikely under current models [1]. The Polymarket contract for a temperature exceeding a specific high threshold currently trades at a 6% YES probability, reflecting the crowd’s view that extreme heat is an outlier event for this coastal location. Traders interacting with this market on Polygon use USDC to buy conditional tokens, where the settlement hinges entirely on the Wunderground daily maximum for the KSFO station, locking in outcomes once the clock strikes 12:00:00Z on the settlement date.

Historical data frames this low probability as rational, given SFO’s maritime climate typically suppresses mid-July peaks. The airport recorded its coldest first half of summer since 1965 recently, with average maximums through mid-July sitting at just 67.6°F [4]. Even during past Bay Area heat waves, SFO Airport peaked at 87°F, far below the inland extremes seen elsewhere in the region [3]. The all-time record for the airport stands at 103°F from September 1971, but July 13 has never approached such figures, reinforcing the market’s skepticism of a YES outcome [7].

Traders should monitor the National Weather Service’s daily climatological reports and real-time radar for any sudden shifts in marine layer coverage, which acts as the primary temperature regulator [8]. While no specific heat dome announcements are active for the Bay Area this week, the dependency on the marine layer’s persistence is critical; a breakdown could theoretically push temperatures toward the 79°F forecast upper bound [1]. The resolution source remains fixed on Wunderground’s KSFO history, meaning traders must watch for data discrepancies or station-specific anomalies rather than regional forecasts alone [10].

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Highest temperature in San Francisco on July 13? 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 Polymarket Scam?, which mirrors the Polymarket order book at 0% fees.

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

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 Polymarket Scam? 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.