April in Milan represents a transitional spring period, with daily highs typically ranging between 15 and 22 degrees Celsius. The 21°C threshold sits comfortably within the expected range for late April weather in northern Italy, making the outcome dependent on specific meteorological conditions. Official weather station data provides objective, measurable resolution with no subjective interpretation required. The 85% YES odds reflect strong market confidence that Milan will experience mild to warm conditions on April 20. Historical climate data shows that temperatures reaching or exceeding 21°C are common during late April in the Milan region, given the seasonal progression toward summer and increased solar radiation. Late spring typically delivers warmer daytime temperatures across northern Italy. Temperature prediction markets offer data-driven resolution—daily highs are precisely measured by meteorological instruments and publicly recorded by authorities within hours of the deadline. This transparency distinguishes weather markets from those requiring human judgment. Market resolution will be determined by the official daily maximum temperature recorded at standardized weather stations in Milan on April 20, 2026, providing clear and verifiable settlement criteria.