Highest temperature in San Francisco on August 5?

Platform comparison

Market context

Polymarket currently has this contract priced around the mid-range, with the market leaning towards a **70–73°F** outcome rather than an extreme heat print or a cool day. On Polymarket, that means traders are paying USDC on Polygon for conditional tokens tied to the final Weather Underground reading at San Francisco International Airport, so the price is the crowd’s live view of where the day’s top temperature will land, not a forecast of comfort in the city centre.[2][12]

That shape is consistent with San Francisco’s August climatology, where highs are typically moderate and tightly clustered, making a mid-70s or low-70s outcome more plausible than a surge into the 80s unless the marine layer breaks down. The key reading for this market is the *highest* temperature recorded at KSFO, which can differ from the wider city and can be nudged by local bay winds, timing of sea-breeze penetration, and the exact hour at which the warmest observation is posted into the historical record.[1][3][8]

For traders, the main catalysts are the day’s forecast updates, any shift in the marine layer or offshore flow, and the final Weather Underground history table for KSFO, since settlement uses that station-specific daily high. Recent local coverage has pointed to a weak sea breeze keeping San Francisco in the 70s even as inland California heats up, which supports a limited upside case rather than a broad temperature spike.[19] Because the market resolves from a single published station record, the last observation and the timing of the next-day data update matter more than headline city forecasts.[12]

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 PolyGram, 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

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 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 PolyGram 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.