Highest temperature in Seattle on July 23?

Platform comparison

Market context

Seattle’s high temperature on 23 July will be set by the peak reading at Sea-Tac Airport, and in a normal July pattern that number usually sits in the mid-70s Fahrenheit rather than anywhere near heatwave territory.[1][4] July at Seattle-Tacoma International Airport is typically warm and dry, with average highs around 73–75°F and only limited rainfall, so the market is really about whether the day lands above or below the seasonal centre rather than an extreme-weather event.[1][4]

The current **0% YES** implies the crowd sees the first settlement band as effectively impossible, which is hard to reconcile with the climate baseline unless the contract’s lowest band is already far above normal July maxima. Sea-Tac’s own historical time-series page is the settlement source, so the relevant reference point is not city-wide Seattle weather but the airport station’s actual daily maximum on the date in question.[2] For comparison, even forecast-style July guides place typical highs near 24°C/75°F, which frames any double-digit Fahrenheit band as an outlier and any low-80s outcome as warm but still plausible.[1][3]

For traders, the main catalysts are the weather pattern over the Pacific Northwest, any late-July marine layer or offshore warming setup, and the final hourly observations that can lock in the day’s maximum before settlement. In crypto terms, this is a straightforward USDC-style oracle event: the payout depends on an external data feed rather than market pricing, so BTC and ETH spot moves matter only indirectly through risk appetite and liquidity conditions. If broader crypto funding rates or whale flows are moving sharply, they may affect secondary-market pricing of the contract, but they do not change the underlying Sea-Tac temperature print.

Sources: 1 · 2 · 3 · 4

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

What are crypto prediction markets?

Crypto prediction markets are on-chain smart contracts where you buy YES or NO shares on a future crypto event (e.g. "BTC above $100k by year-end"). The market price between 0¢ and 100¢ is the implied probability.

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.

Can I use Bitcoin directly?

No, Polymarket operates exclusively in USDC on Polygon. You can bridge BTC to USDC via an exchange or bridge service and deposit on Polygon — typically 10-30 minutes processing time.

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.

Which crypto markets exist on Polymarket?

Currently active markets include BTC/ETH/SOL price targets, halving dates, ETF approvals, hard-fork outcomes and Layer-2 TVL thresholds. The list updates weekly; biggest volume sits on BTC and ETH price forecasts.