Highest temperature in Paris on August 11?

Platform comparison

Market context

Polymarket is pricing this Paris heat contract at **0% YES** right now, so on-chain traders using USDC on Polygon are effectively saying the listed outcome ranges are not yet receiving a bid. Because settlement is tied to the **Daily Observations** table for Paris-Le Bourget Airport on Weather Underground, not the summary high/low panel, the practical question is the highest Celsius reading logged before the first datapoint for 12 August is published.[1]

The current setup is unusual in that the market’s crowd-implied favourite elsewhere is 32°C, while local forecast services are pointing to a hot but not extreme day, with AccuWeather showing about **91°F / 33°C** and an official-style warning for extreme high temperatures running through the day.[1][11][16] That sits well within August norms for Paris, where historical climate pages show typical highs around the mid-20s Celsius and past August extremes reaching the high 30s to about 39.5°C on 11 August 2003.[4][12][14] For a Polymarket user, the key is that these contracts settle from an actual station reading, so forecast headlines matter only insofar as they move the probability of the final observed peak.[1]

A trader watching this market should focus on the timing of the Paris heatwave advisory, the intraday evolution of the Le Bourget station readings, and whether the peak is captured before evening cooling or late-afternoon convection. The resolution source allows revisions until the next day’s first datapoint appears, so any late correction in Weather Underground’s history can still affect settlement if it lands inside the window.[1] Competitive pressure is likely to come from nearby forecast updates rather than a single announcement, because the market is a direct claim on the eventual conditional token payout, redeemed at $1 if the relevant temperature band resolves.[1]

Sources: 1 · 2 · 3 · 4 · 5

Methodology

We track Highest temperature in Paris on August 11? 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.

FAQ

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.

What does Polymarket cost to trade?

Polymarket itself charges 0% — the only cost is the Polygon network fee, typically under $0.01 per transaction. Off-chain venues like Kalshi or Betfair charge 2-7% commission.

How fast are USDC deposits?

Polygon credits deposits after 12 confirmations — usually under 30 seconds. Withdrawals follow the same path and land back in your wallet within minutes.

Do I need to KYC for this market?

On Polymarket directly, no — it's wallet-based. Intermediary brokers like PolyGram trigger KYC only above $1,500 of lifetime trading volume; under that you trade pseudonymously with a single wallet address.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.