Highest temperature in NYC on August 17?

Platform comparison

Market context

On 17 August 2026, the highest temperature recorded at LaGuardia Airport will fall into one of several defined ranges. In prediction markets, a YES share means you're betting that outcome occurs; a NO share means it won't. Here, traders are essentially wagering on whether New York's peak summer heat that day will exceed a specific threshold. The current 1% implied probability suggests the crowd believes an unusually high reading is unlikely—a meaningful signal given that August in New York typically sees temperatures in the upper 70s to mid-80s Fahrenheit.

Historical August data from LaGuardia shows that temperatures above 90°F occur in roughly 40–50% of years, whilst readings exceeding 95°F are considerably rarer, appearing in perhaps one in five Augusts. The market's resolution hinges on Weather Underground's Daily Observations table rather than summary figures, a distinction that matters because automated station readings can occasionally diverge from rounded daily highs. This technical specification reduces ambiguity but requires traders to understand which data source will govern the outcome.

The National Weather Service issues seasonal outlooks and monthly forecasts that traders should monitor as August 2026 approaches. Broader climate patterns—including Atlantic sea-surface temperatures and the position of the jet stream in early summer—typically influence whether the northeastern United States experiences a heat dome or more moderate conditions. Real-time weather forecasts become actionable only in the final week before settlement, but longer-range climate signals available months in advance can shift expectations about the probability of extreme heat.

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

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.

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 Prediction Market UK. 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%.