Forecast consensus from KNMI and Met Office models supports the near-certain 21°C market outcome for Amsterdam’s daily maximum on August 17, driven by post-heatwave cooling, a northwest airflow bringing cooler North Sea air, and extensive cloud cover with light showers that limit solar heating. Current observations and model runs show daytime peaks stabilizing near 20–21°C, well below August climatological averages in the mid-20s. This positioning reflects traders’ assessment of stable atmospheric conditions and official guidance through the resolution window. An unexpected rapid clearing of clouds or stronger southerly flow could allow brief warming to 22°C or above, though such shifts remain low-probability given the entrenched marine influence and persistent overcast.