Highest temperature in Seattle on August 16?

Platform comparison

Market context

The market concerns the highest temperature recorded at Seattle-Tacoma International Airport on 16 August 2026, with settlement based on Weather Underground's Daily Observations table rather than summary figures. The crowd currently assigns zero probability to any outcome occurring, a position that warrants scrutiny given the certainty of a measurable temperature on that date.

Seattle's August climate shows consistent patterns across decades. Historical data from the National Weather Service indicates that mid-August highs in the Seattle area typically range between 75°F and 82°F, with extreme readings above 90°F occurring roughly once per decade. The 1994 heat wave produced readings near 96°F, whilst more recent Augusts have clustered towards the cooler end of the range. The 0% crowd probability reflects either a technical issue with market setup or genuine confusion about settlement mechanics, since a temperature reading is meteorologically inevitable.

Traders should monitor Pacific Northwest weather patterns from late July onwards, particularly the position of high-pressure systems and any ridge development that could drive anomalous warmth. The National Oceanic and Atmospheric Administration's seasonal outlooks, typically released in early August, will provide guidance on whether conditions favour above or below-normal temperatures for that specific week. El Niño or La Niña conditions in the preceding months could influence atmospheric circulation patterns affecting the Pacific Northwest. The resolution mechanism's reliance on Weather Underground's specific Daily Observations table rather than official National Weather Service records introduces a minor dependency worth confirming before settlement approaches.

Methodology

We track Highest temperature in Seattle on August 16? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

Resolution & payout

Polymarket-based markets settle through the UMA Optimistic Oracle on Polygon. A proposer submits the outcome, a two-hour challenge window opens, and unchallenged proposals finalise the resolution. Payouts settle automatically in USDC the moment the result is final — no bookmaker, no delay.

Kalshi-based markets settle in USD via the CFTC-regulated clearinghouse. Betfair Exchange settles in GBP/EUR net of commission. Manifold is play-money and does not pay out real funds.

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 Who Will Win 2026. 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.

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.

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.