Highest temperature in Paris on August 27?

Platform comparison

Market context

Paris has been running warmer than its late-August average, with the Le Bourget station still showing a high-20s Celsius reading late on 26 August and nearby outlets carrying forecasts of thundery showers on 27 August rather than a clean heat spike. That leaves the day’s high more likely to be set early, before cloud and convection build, which matters because this contract settles on the single highest NOAA temperature reading through 12:00 UTC, not an end-of-day city average.

The current 0% YES implies the market is pricing the contract as effectively dead on arrival, but that can happen when the settlement window is short and the first available readings are already locked in. Comparable late-summer Paris setups have often hinged on whether overnight warmth carries into the morning or whether showers cap the peak well below the sort of 35–40°C readings seen during earlier August heat episodes; the most relevant reference point is the station-level NOAA trace at Paris–Le Bourget, with Weather Underground only a fallback if the official feed fails. The on-chain angle is straightforward: settlement should be in USDC on a temperature band outcome, so traders are really positioning around the first few hours of published observations rather than a broad forecast for the city.

The key catalyst is the actual hourly NOAA print from Le Bourget before the 12:00 UTC cut-off, since a sharp early-morning rise or an unexpected sunny break would be the only way to reopen upside. If the station feed is incomplete, the fallback source can matter, but the contract description makes NOAA primary, so any deviation in the published sequence or a delayed observation is what could move the final range.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page reads Highest temperature in Paris on August 27? on-chain. Polymarket's quote comes directly from the Polygon order book — the only comparable venue with on-chain settlement. Kalshi (USD, off-chain), Betfair (GBP/EUR, off-chain) and Manifold (play-money) are listed alongside for venue context. Every CTA routes to BTC Prediction, which mirrors the Polymarket order book directly.

Resolution & payout

Settlement is on-chain via UMA Optimistic Oracle. A proposer posts the outcome with a bond, a two-hour dispute window opens, then the smart contract lifts winning conditional tokens to 1 USDC and sends payments to holders' wallets automatically. No withdrawal fees beyond Polygon gas.

Off-chain venues (Kalshi, Betfair, Smarkets) settle in local fiat through bank-side clearing — faster than SWIFT, slower than on-chain. Manifold pays no real cash.

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