Highest temperature in NYC on August 27?

Platform comparison

Market context

Polymarket has this contract at 0% YES, which implies the market is pricing no chance that the LaGuardia-based NOAA high on 27 August will fall into the specified winning band. The event is narrow and mechanical: settlement depends on the highest value in NOAA’s hourly temperature data for KLGA on the day, with the fallback to Weather Underground only if NOAA is missing, so traders are really pricing a single station reading rather than a citywide average or forecast outcome.

For context, late August in New York often sits near the low-to-mid 80s Fahrenheit on warm days, but the station can swing higher when humidity and a stalled heat pattern build over the city. Recent local coverage has repeatedly pointed to heat advisory conditions in early August, with forecasters warning of feels-like temperatures around 95 to 100 degrees and intermittent thunderstorms. That matters because a contract like this can move sharply if the day turns hot early, but it is also vulnerable to cloud cover, onshore flow, or storm outflows that cap the peak at LaGuardia.

Traders watching the tape should focus on the day’s NWS outlooks, any heat advisories, thunderstorm timing, and the midday to afternoon evolution at KLGA, since that is when the top hourly temperature is usually set. On-chain, positions settle through conditional tokens on Polygon, with USDC as the quoted stake, so price changes reflect how users are reading the weather data path rather than a broader NYC climate view.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in NYC on August 27? 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

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.

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%.