Highest temperature in Paris on August 19?

Platform comparison

Market context

On 19 August 2026, the highest temperature recorded at Paris-Le Bourget Airport will determine which temperature band resolves YES. Polymarket currently prices all outcomes at 0%, reflecting the market's nascent state roughly two years before settlement; USDC liquidity on Polygon remains sparse, typical for weather contracts with distant settlement dates. The resolution hinges on Weather Underground's Daily Observations table rather than the Day High & Low summary, a distinction that matters when automated station readings diverge from manual adjustments—traders should verify which source Wunderground prioritises during August 2026.

Paris-Le Bourget has recorded August highs ranging from 23°C to 36°C over the past two decades. The 2003 European heatwave saw temperatures exceed 38°C across northern France, whilst cooler Augusts in 2015 and 2021 peaked near 25–27°C. August typically ranks as Paris's warmest month, though Atlantic weather systems can suppress temperatures mid-month. Historical volatility suggests outcomes spanning 25–34°C remain plausible, yet the 0% crowd probability indicates minimal conviction across all bands at present.

Traders should monitor European weather forecasting updates from mid-August 2026, particularly from Météo-France and the European Centre for Medium-Range Weather Forecasts. Anomalous heat patterns across the continent often signal conditions affecting Paris; conversely, Atlantic low-pressure systems can deliver cooler spells. The conditional token structure on Polygon means positions remain illiquid until nearer the settlement window, but early entry captures potential mispricing as forecasts sharpen and liquidity accumulates.

Methodology

This page reviews Highest temperature in Paris on August 19? across five venues. The live probability is the Polymarket mid-price, sourced directly from the on-chain Polygon order book; the comparison columns benchmark each venue on fee structure, KYC, settlement currency and payment rails. Every CTA routes to PolyGram, which mirrors the Polymarket order book at 0% fees.

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

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

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.

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%.