Highest temperature in Seattle on August 4?

Platform comparison

Market context

Seattle-Tacoma International Airport had already printed a warm August high in the low 80s by the forecast window’s end, which is why the market had been anchored near the 0% YES line for any much higher bin rather than pricing a late surge. Seattle’s August climate norm is much cooler than the early-80s readings shown in recent monthly summaries, so the key move in the last 24-48 hours has been a modest warm-up rather than an extreme heat signal.[1][9]

For context, Seattle’s summer highs usually cluster well below the upper-80s and 90s, and even August averages sit around the upper 70s, so a print in the low-to-mid 80s is the more typical “hot day” outcome rather than an outlier. Recent market snapshots elsewhere have also centred on the low 80s, with one live market showing an 83°F main line and broader interest concentrated around the 82-85°F band, which is consistent with a normal late-summer warm spell rather than a record-chasing event.[3][4]

The main catalysts are the official airport observations on the day itself, especially the timing of the day’s peak reading before the settlement window closes, because the market resolves to the highest temperature recorded at Seattle-Tacoma International Airport Station on 4 August. Traders should watch any short-term forecast updates, smoke or cloud cover changes, and offshore or northerly wind shifts that can cap afternoon warming; the National Weather Service climate record and daily reports are the relevant reference points for comparing whether the day stays near seasonal norms or edges into an unusually warm band.[8][19]

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 Prediction Today, which mirrors the Polymarket order book directly.

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 Prediction Today. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.

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.