Highest temperature in NYC on August 17?

Platform comparison

Market context

The market is pricing the probability of New York City recording a specific high temperature range at LaGuardia Airport on 17 August 2026, with the crowd currently assigning 0% likelihood to the YES outcome. The resolution hinges on the Daily Observations table from Weather Underground rather than summary figures, a distinction that matters when automated stations record granular readings throughout the day.

August temperatures at LaGuardia typically peak between 82°F and 88°F, with historical data showing the airport rarely exceeds 90°F during mid-August. The 17th sits in the latter half of summer when heat waves have usually broken across the Northeast, though extreme outliers do occur—the station recorded 96°F on 17 August 1988. The 0% crowd probability suggests traders are either confident the YES range sits well outside historical norms or the market has attracted minimal participation, leaving little consensus to challenge.

Traders should monitor late-July and early-August weather patterns across the Atlantic basin, as ridge positioning determines whether tropical moisture or Canadian air dominates the Northeast by mid-month. The National Weather Service issues extended forecasts roughly two weeks ahead; any signals of anomalous heat or unusual blocking patterns would shift expectations. Sea surface temperatures in the Atlantic and Gulf Stream positioning influence August weather trajectories, though predictability beyond ten days remains limited. Current atmospheric conditions favour typical late-summer temperatures rather than extremes, which may explain the flat pricing, though the settlement window's distance means material shifts remain possible.

Methodology

We track Highest temperature in NYC on August 17? 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

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

UK Frequently Asked Questions

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. 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.

Is Polymarket legal in the UK?

Polymarket is accessible to UK traders but is not UKGC-licensed. It operates under US CFTC jurisdiction. UK residents face no domestic legal prohibition on using it, but UKGC consumer protections do not apply. For UKGC-regulated alternatives, Betfair Exchange and Smarkets offer similar prediction-style markets.

Do I pay tax on prediction market profits in the UK?

UKGC-licensed platform profits (Betfair, Smarkets) are typically tax-free gambling winnings for UK individuals. Polymarket profits involve USDC crypto transactions, which HMRC treats as Capital Gains Tax events. Keep full transaction records and report via Self Assessment if gains exceed £3,000 per tax year.

How do I deposit on Polymarket from the UK?

UK traders typically fund Polymarket via Coinbase UK, Kraken or Revolut — buying USDC with GBP and transferring to a Polygon-compatible wallet (MetaMask, Coinbase Wallet). Polymarket's onboarding walks you through the bridging process. Typical GBP-to-USDC conversion costs 0.5–1%.