Official meteorological observations from Spain's State Meteorological Agency confirmed a maximum temperature of 20°C in Madrid on May 16, driving the market's near-certain 100% implied probability for this outcome. This reading aligns with mid-May climatological norms for the Iberian Peninsula, where spring warming patterns typically produce daily highs in the 18–22°C range under stable high-pressure systems. Forecast models from the European Centre for Medium-Range Weather Forecasts had projected minimal deviation from these baselines in the 48 hours prior, with no significant heat advection or urban heat-island amplification observed. While final official reports can occasionally undergo minor revisions for instrumentation checks, historical precedent shows such adjustments rarely exceed 1°C after initial publication, leaving little realistic scope for market-moving changes.