Highest temperature in Seattle on July 23?

Platform comparison

Market context

Seattle’s temperature profile still points to a fairly tight summer range, with July daytime highs typically in the mid-70s Fahrenheit and only rarely pushing much above the upper 80s. AccuWeather’s July 2026 outlook for Seattle shows highs mostly between **66°F and 82°F**, while Weatherspark puts the typical July high around **74°F to 79°F** and notes that readings above **88°F** are uncommon.[1][2] That backdrop helps explain why the market’s **0% YES** pricing is not especially surprising: traders are effectively saying the airport’s top reading on the day is unlikely to land in a much hotter band than normal.

For comparison, Seattle’s summer warmth tends to be shaped more by dry, stable conditions than by extreme heat, with July generally one of the city’s drier months and long daylight hours allowing temperatures to build into the afternoon.[2][3] Forecast products also suggest the month is running within a moderate envelope rather than an extreme one, which reduces the odds of an outlier spike at Seattle-Tacoma International Airport.[1][6] In that context, the market is best read as a question of whether the day gets a brief late-afternoon push into a higher bracket, not whether Seattle turns hot in a broader sense.

What traders will watch now is the day’s airport high as published on the resolution source, since the settlement depends on the highest temperature recorded at Seattle-Tacoma International Airport across all hours of the day.[4] The key catalyst is whether any late-day warming, cloud cover, or marine influence changes the afternoon peak; once the daily high is set, there is little room for the market to move unless updated airport observations or a revised weather history page alters the final reading.[4] Current July forecast ranges still cluster around the low 80s at the warm end, which leaves the upper brackets dependent on a clean heat spike rather than routine summer conditions.[1][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

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.

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.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like Prediction Today 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.