Highest temperature in NYC on August 18?

Platform comparison

Market context

New York City's weather on 18 August 2026 will be measured by the highest temperature recorded at LaGuardia Airport's weather station that day. The resolution hinges on Weather Underground's Daily Observations table rather than their summary high-low display—a distinction that matters when automated feeds pull data. For traders building conditional orders or bots around this market, the source specification is critical: you're tracking a single station's peak reading, not a citywide average or alternative reporting method.

Historical August temperatures at LaGuardia show the median daily high around 82–84°F, with readings above 90°F occurring roughly once every two to three years during the summer months. The 1% crowd probability suggests the market is pricing in an exceptionally hot day—likely above 95°F or higher. Comparable heat events in the Northeast, such as the July 2019 heatwave that pushed readings to 96°F at LaGuardia, provide calibration points for how often such extremes materialise in peak summer conditions.

Traders monitoring this market should track National Weather Service forecasts released in early August 2026 and watch for Atlantic hurricane activity or high-pressure systems that could drive unusual heat into the region. Seasonal climate patterns, including any El Niño or La Niña conditions active that summer, will shape baseline expectations. Programmatically, you'd want to establish a data pipeline pulling historical August records from Weather Underground's archive to model distribution shifts, then compare real-time forecasts against those baselines as the settlement date approaches.

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to Polymarket Review UK, which mirrors the Polymarket order book directly.

Resolution & payout

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

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 Polymarket Review UK. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

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.

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%.