Highest temperature in Seattle on August 4?

Platform comparison

Market context

Polymarket is pricing the Seattle-Tacoma International Airport temperature contract through USDC on Polygon, with the crowd currently assigning **0%** to the **YES** side for this specific range. In practice, that means traders are treating the chance of the day’s high landing in the resolved bucket as negligible, even though settlement will ultimately follow the Weather Underground reading for KSEA and not a broader Seattle headline temperature.

For context, Seattle in early August usually sits in the warm-but-not-extreme part of its annual cycle, so the market is more about identifying a one-day spike than a seasonal average. AccuWeather’s monthly outlook for Seattle shows an August daily high around **75°F**, while WeatherSpark’s climate history describes August as one of the city’s warmer months overall, but still typically moderated by marine influence. That makes high-end outcomes dependent on a brief inland push, rather than on baseline summer conditions alone.[1][9]

A trader watching this market would focus on the ingredients that lift the airport reading above normal: offshore ridging, sunny skies, and any warm-air advection ahead of the day itself. The current event page already reflects that kind of setup, noting warmer, sunnier conditions and a likely high in the low-to-mid 80s, while the contract only settles once Weather Underground posts the first observation for the following calendar day, locking in the final maximum.[4][3] For hands-on Polymarket users, that means the live quote can move on forecast updates, but the eventual payout is governed by the airport station’s archived hourly history rather than general city weather chatter.[3][4]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reviews Highest temperature in Seattle on August 4? across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to Kalshi UK, which mirrors the Polymarket order book at 0% fees.

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 Kalshi UK. 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 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.

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.