Highest temperature in NYC on August 9?

Platform comparison

Market context

Polymarket currently prices the LaGuardia Airport high for 9 August in the **90–91°F** band at **73%**, with **92–93°F** next at **20%** and the rest of the curve thinly priced, so the contract is trading as a strong but not absolute lean towards a hot day rather than an extreme heat spike.[1] For a user buying shares with USDC on Polygon, that matters because settlement depends on the **highest reading in Weather Underground’s Daily Observations table**, not the simpler day summary, and the market will resolve to the temperature range containing that recorded maximum.[1]

Recent comparable pricing suggests traders tend to anchor these NYC temperature markets near the forecasted daily high unless the late-day observation window points to a different peak. Weather Underground data shown for LaGuardia in the same period already printed an **88.0°F** latest report with a **89.1°F** six-hour high, which helps explain why the front of the book sits just below the low-90s rather than in a cooler bucket.[2] In practical terms, the 0% YES framing does not mean the event is impossible; it usually reflects that the current price model sees one band as overwhelmingly favoured and the contract is still more about fine-tuning the exact bin than betting on a binary shock.[1]

The main trader catalysts are the station’s actual afternoon maximum, any late adjustment to the Daily Observations table, and the publication of the next day’s first datapoint, because revisions before that cut-off still count while later changes do not.[1] Forecast updates from the National Weather Service around LaGuardia, plus any shift in model guidance from major weather services, can move the implied range if the realised high looks likely to drift above or below 91°F.[1][10] Because settlement is tied to a specific station and source hierarchy, the key dependency is not citywide conditions but whether KLGA’s observed peak lands inside 90–91°F, 92–93°F, or another listed bin.[1]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in NYC on August 9? 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.

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%.