Highest temperature in San Francisco on July 13?

Platform comparison

Market context

San Francisco International Airport faces a rare heat spike tomorrow as traders bet on whether the highest temperature will breach the threshold implied by the current 6% YES probability. July in San Francisco typically sees daily highs around 70°F, rarely exceeding 79°F, making an extreme outlier event statistically unlikely under normal conditions[1]. Historical data shows the airport’s all-time record high is 87°F, set during a Bay Area heat wave that tied a 1973 mark, while the broader region saw triple-digit temperatures elsewhere[2]. Even on July 13 specifically, the 1972 record in Healdsburg reached 116°F, but KSFO has never approached such extremes, suggesting the 6% odds reflect a genuine tail-risk scenario rather than a mispriced consensus[3].

Traders should monitor real-time forecasts from Wunderground and NOAA for any sudden shifts in marine layer breakdown or inland heat advection, which are the primary catalysts for anomalous airport temperatures[9]. A recent Bay Area heat wave demonstrated how quickly records can shatter when the usual coastal fog fails, with KSFO hitting 87°F under similar conditions[2]. No official announcements are scheduled for tomorrow, but the settlement depends entirely on the highest recorded temperature at KSFO by 12:00 UTC on July 13, 2026, as verified by Wunderground’s daily history page[9]. Cross-platform odds may diverge if sportsbooks adjust lines based on emerging forecast models, while prediction markets like Polymarket could lag if they lack access to live meteorological updates.

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 Kalshi vs Polymarket, which mirrors the Polymarket order book directly.

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

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's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Kalshi vs Polymarket 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.