Seoul experiences variable spring weather in mid-April, typically ranging between 12–20°C for daily highs as the city transitions from cooler spring conditions into warmer months. This market tracks whether Seoul's official high temperature will land on exactly 18°C on April 19, 2026. Because weather forecasting has inherent uncertainty and hitting a precise single-degree temperature is statistically rare, the 1% YES odds reflect the slim probability of this exact outcome. The market resolves using official data from Korea Meteorological Administration weather stations, ensuring objective and verifiable resolution. At these odds, traders are pricing in the specificity of the target—unlike broader markets asking "will it be above 15°C," this requires pinpoint accuracy on a daily high. The low current volume and tight liquidity suggest limited interest in this exact threshold, which is typical for micro-weather prediction markets. Historical April temperature patterns in Seoul show most daily highs fall across a wide range, so achieving exactly 18°C remains a low-probability event despite being meteorologically possible within the city's typical spring range.