Highest temperature in NYC on August 9?

Platform comparison

Market context

LaGuardia’s observed high on 9 August is the deciding input, so the practical issue is not the headline forecast but the exact maximum logged in Weather Underground’s **Daily Observations** table before the first datapoint for 10 August is published. A recent WeatherSpark capture for KLGA showed 88.0°F at 17:51 UTC with an hourly high of 89.1°F, while the National Weather Service’s daily climate report for New York City put the prior day’s maximum at 87°F, underlining how quickly these airport highs can move within a single afternoon.[1][3]

For a trader reading the current 0% yes price, the key historical frame is that late-summer New York City highs often cluster in the upper 80s to low 90s, but the market settles on a range, not an exact reading. AccuWeather’s August outlook has 9 August at 90°F, which sits in the same neighbourhood as the live KLGA observation and the market’s chosen bin structure.[2] Programmatically, this is the kind of market that is best monitored by polling the source page, parsing the highest value in the Daily Observations table, and comparing it with the active bracket mapping rather than relying on the summary high/low box.[4][5]

Catalysts are limited once the day is underway: the main dependencies are the station’s observation cadence, any late data revisions, and the publication time of the first 10 August entry, because that is the cutoff for accepted adjustments.[4] Weather Underground’s KLGA page and WeatherSpark’s mirror-style historical display are the useful live checks, while the NWS climate products help contextualise whether the day is tracking above or below seasonal norms.[1][12]

Sources: 1 · 2 · 3 · 4 · 5

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%.