Highest temperature in Seattle on July 23?

Platform comparison

Market context

Polymarket prices this contract at **0% YES**, with traders effectively saying Seattle-Tacoma International Airport is not expected to post the specified daily high on 23 July 2026. On Polymarket, that view is expressed through USDC on Polygon and resolved through conditional tokens, so the market price reflects the crowd’s current reading of the terminal airport observation rather than a generic Seattle forecast.

For context, Seattle’s July climate is usually mild rather than extreme: typical highs are around **23–24°C (73–75°F)**, with warm, dry afternoons and cooler evenings, and July rainfall is usually limited.[1][4] That makes the present pricing a comment on the chance of an unusually hot day, not on the ordinary seasonal baseline. The closest recent analogue in the supplied results is a 2024 Seattle heat episode, when forecasts reached the mid-80s and local reporting noted heat advisories across western Washington, showing that brief spikes above the norm are possible even in a maritime climate.[5]

A trader watching this market would focus on whether late-July synoptic patterns bring a warm, dry ridge over the Pacific Northwest, which is the main setup for a materially higher airport maximum. The settlement source is Wunderground’s daily history page for SEA-TAC, and the relevant value is the highest temperature recorded at the station during the day, so intraday conditions matter more than a single forecast headline.[2] The practical catalysts are weather-service updates, aviation-area forecast changes, and any heat-related local coverage that signals a shift towards a hotter-than-usual air mass.[2][5]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

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 PolyGram. 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.

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.

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.