Highest temperature in San Francisco on July 14?

Platform comparison

Market context

San Francisco’s peak heat on 14 July 2026 will be measured at the San Francisco International Airport Station, with settlement based on the highest Fahrenheit reading recorded that day via Wunderground. The market resolves to the temperature range containing that peak, settling in USDC on-chain by 12:00 UTC on 15 July 2026.

Historical July highs in San Francisco typically cluster between 78°F and 82°F, with the 80–81°F range proving most frequent in recent years. Current crowd-implied probability shows 0% for any YES outcome on a specific binary, yet the Polymarket equivalent assigns 40% to 80–81°F and 30% to 78–79°F, suggesting traders expect a warm but not extreme day [1]. This distribution aligns with coastal moderation patterns, where marine influence usually caps temperatures below 85°F even during inland heatwaves.

Traders should monitor the National Weather Service’s 7-day forecast for the Bay Area, particularly any incoming ridge of high pressure or marine layer breakdown, which could push temperatures higher. A sudden shift in funding rates on BTC or ETH perpetuals, or large whale inflows into USDC on-chain, may signal macro risk-off sentiment that indirectly affects liquidity in weather-linked contracts. Recent crypto-market volatility, as tracked by CoinGlass funding rate data, has occasionally correlated with reduced depth in niche prediction markets, making timing of entry critical [1].

Sources: 1

Methodology

Methodologically this overview focuses on on-chain pricing: Polymarket's live mid comes from the Polygon conditional-token order book and settles automatically in USDC. The other three venues — Kalshi, Betfair, Manifold — sit alongside as off-chain reference points so you can see how the contract translates across regulatory and settlement regimes.

Resolution & payout

Settlement is on-chain via UMA Optimistic Oracle. A proposer posts the outcome with a bond, a two-hour dispute window opens, then the smart contract lifts winning conditional tokens to 1 USDC and sends payments to holders' wallets automatically. No withdrawal fees beyond Polygon gas.

Off-chain venues (Kalshi, Betfair, Smarkets) settle in local fiat through bank-side clearing — faster than SWIFT, slower than on-chain. Manifold pays no real cash.

FAQ

Why USDC and not ETH or USDT?

USDC is the Polygon standard — audited reserves (Circle, monthly attestation), deepest order book, low gas costs. ETH volatility would distort probability quotes; USDT has thinner Polygon liquidity than USDC.

What does a transaction cost on Polygon?

Polygon gas is typically under $0.01 per transaction. A full trade cycle (Approve + Order + Fill) totals around $0.03 — compared to $5-50 on Ethereum mainnet.

How does UMA secure the resolution?

The UMA Optimistic Oracle uses a bond system: a proposer posts a bond, a two-hour challenge window opens. On dispute the losing side forfeits the bond — financial incentive for honest resolution.

How volatile are crypto prediction markets?

Crypto markets react to spot prices — a 5% BTC move typically shifts a "BTC above X by date" market 10-20%. Polymarket crypto market liquidity is usually six-figure USD, sufficient for active trading.

Are crypto prediction markets taxable in the US?

In the US, prediction market gains are typically treated as ordinary income or short-term capital gains depending on holding period. Consult a tax professional for your specific situation — we cannot provide tax advice.