Highest temperature in NYC on August 6?

Platform comparison

Market context

LaGuardia’s high temperature on 6 August is tracking as a classic late-summer NYC weather bet, but the market is treating the upper 80s to low 90s as the main lane. The current crowd-implied favourite is **88–89°F at 43%**, with **90–91°F close behind at 42%**, so the consensus is effectively split between a warm but not extreme afternoon and a slightly hotter outcome. The **0% YES** print is hard to reconcile with those live prices, which makes the market look more like a pricing anomaly than a genuine consensus on a nil-probability result.

Historically, early-August New York highs often cluster around the high 80s, with occasional pushes into the low 90s when heat and humidity build together, so the favourite has a reasonable weather-logic anchor. AccuWeather’s August view has 6 August at **88°F**, which sits neatly on the boundary between the two leading buckets and helps explain why the book is tight rather than one-sided. In handicapper terms, the favourite is the high-80s band, but the underdog is not far away and has real live value if forecasts firm up towards the lower 90s.

Traders should watch the same-day National Weather Service updates, especially any Heat Advisory language, as well as hour-by-hour timing of cloud cover, sea-breeze effects and late-afternoon convection, because the market resolves to the day’s *highest* reading at LaGuardia rather than the citywide average. USA Today reported that New York was heading into a stretch of dangerous heat and humidity with actual temperatures expected in the upper 80s and lower 90s, while heat index values could run far higher; that supports a range-bound view rather than a blowout upside case.[11] The value spot is usually whichever adjacent band is underweighted once the morning observation trend becomes clear.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

Methodologically we separate two layers: the live probability (Polymarket mid-price) and the platform attributes (fee, KYC, settlement currency, payment rails). That keeps the comparison honest — a single canonical probability across the row, with the venue-by-venue trade-offs spelt out in the columns next to it.

Resolution & payout

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

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 Who Will Win. 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%.