April 18 is early spring in Paris, with typical highs ranging from 12 to 18 degrees Celsius depending on the season and weather patterns. This market specifically predicts whether the highest temperature recorded on April 18 will be exactly 15°C—a precise outcome that requires ideal conditions. The current 0% YES odds reflect the extremely low probability traders assign to this exact outcome. Weather resolution markets depend on official Météo-France or similar meteorological data sources, typically recorded at standardized weather stations. A 0% price indicates strong consensus that either Paris will be warmer or cooler than 15°C on that date. Temperatures during April in Paris typically fluctuate between 8 and 18°C, making many specific point-estimates unlikely. This market updates continuously as new weather forecasts emerge and the date approaches. The sub-penny pricing on weather outcomes with low probability shows how precise these markets can be. Traders use historical weather data and seasonal patterns alongside modern weather forecasting models to assess outcomes. Resolution occurs after April 18 ends, when actual recorded highs are published by official sources.