Highest temperature in San Francisco on June 30?

Platform comparison

Market context

On 30 June 2026, the San Francisco International Airport Station will record its peak temperature for the day, a metric that determines the outcome of this prediction market. The crowd-implied probability of a “YES” is currently 0%, reflecting a consensus that the temperature will fall within the lowest expected range. This stance aligns with historical patterns: June in San Francisco typically sees average highs near 70°F, with recent data from mid-to-late June 2026 showing a peak of just 72.6°F [3]. Even the all-time record for June, 103°F on 14 June 2000, is an outlier that has not been repeated in over two decades [5][8].

Traders should monitor incoming heatwave forecasts and atmospheric river disruptions, as these are the primary catalysts for anomalous temperature spikes. While no major heat event is currently forecast for late June 2026, the Bay Area remains vulnerable to rapid shifts driven by Pacific pressure systems. Recent reporting from the San Francisco Chronicle highlights how the region can shatter temperature records unexpectedly, such as the 92°F downtown reading in March 2026 that tied a 149-year-old record [4]. The value spot may lie in contrarian positions if a sudden marine layer breakdown occurs, pushing temperatures above the consensus range despite the 0% implied probability.

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, 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. 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 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.

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.