Recent forecast updates from Brazil’s INMET and international models indicate a warmer-than-average air mass over São Paulo, positioning the 23°C-or-higher outcome as the clear market leader at 78%. A delayed cold front and reduced cloud cover have allowed greater daytime heating, with ensemble guidance now clustering daily maxima near 22–24°C for May 17. This aligns with May’s historical range, where highs occasionally reach the mid-20s when subtropical flow strengthens. Traders have adjusted probabilities upward for the top band as new model runs reduce the chance of a sharper cooldown, though any overnight front acceleration could still cap readings near 21–22°C.