Recent weather model consensus from the South African Weather Service and global ensembles points to a maximum temperature of 20–22°C in Cape Town on May 18, explaining the tight clustering of market-implied probabilities around these outcomes. Autumnal conditions driven by the South Atlantic High and the cooling influence of the Benguela Current are keeping daytime highs near seasonal norms of 19–21°C, with minimal diurnal warming expected under partly cloudy skies. Minor shifts in forecast wind patterns or cloud cover could nudge the peak into the 19°C or 23°C bins, which together hold roughly 22% combined probability. Updated model runs through May 17 will likely determine whether traders further consolidate around 21°C.