Highest temperature in NYC on August 6?

Platform comparison

Market context

The relevant outcome is the **official LaGuardia Airport high temperature** reported for 6 August, not an aggregate for Manhattan or a “feels like” reading. The contract resolves from Weather Underground’s KLGA daily history page, and the market is currently pricing **0% YES**, which implies traders do not expect the final recorded high to land in the contract’s YES range. [7][4][1]

That pricing sits against a fairly warm late-summer baseline. Forecast products for New York on 6 August showed highs around the upper 80s Fahrenheit, with AccuWeather listing **88°F** for the day and a separate weather report describing actual temperatures peaking in the **upper 80s to lower 90s** under a Heat Advisory. Comparable August readings in New York commonly cluster in that zone, so the market is effectively asking whether LaGuardia prints a number high enough to clear the relevant threshold rather than merely hitting a typical hot-day maximum. [3][11][16]

For traders, the key catalysts are the afternoon temperature trajectory, any NWS heat advisories or forecast revisions, and whether sea-breeze or storm-driven cooling caps the airport reading below the bracket in play. Because the settlement source is a single airport station, small local effects matter more than citywide averages, and the final print can diverge from downtown forecasts. On the crypto side, there is no direct on-chain driver embedded in the contract, so BTC or ETH spot, funding, and whale flows matter only insofar as they affect overall risk appetite and USDC deployment into prediction markets rather than the weather outcome itself.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically this overview focuses on on-chain pricing: Polymarket's live mid comes from the Polygon conditional-token order book and settles automatically in USDC. The other three venues — Kalshi, Betfair, Manifold — sit alongside as off-chain reference points so you can see how the contract translates across regulatory and settlement regimes.

Resolution & payout

Settlement is on-chain via UMA Optimistic Oracle. A proposer posts the outcome with a bond, a two-hour dispute window opens, then the smart contract lifts winning conditional tokens to 1 USDC and sends payments to holders' wallets automatically. No withdrawal fees beyond Polygon gas.

Off-chain venues (Kalshi, Betfair, Smarkets) settle in local fiat through bank-side clearing — faster than SWIFT, slower than on-chain. Manifold pays no real cash.

UK Frequently Asked Questions

What are crypto prediction markets?

Crypto prediction markets are on-chain smart contracts where you buy YES or NO shares on a future crypto event (e.g. "BTC above $100k by year-end"). The market price between 0¢ and 100¢ is the implied probability.

Why USDC and not ETH or USDT?

USDC is the Polygon standard — audited reserves (Circle, monthly attestation), deepest order book, low gas costs. ETH volatility would distort probability quotes; USDT has thinner Polygon liquidity than USDC.

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%.