Recent model guidance from GFS and ECMWF indicates Sao Paulo’s overnight low on October 6 will likely fall between 17–19 °C, with the exact value hinging on the timing and strength of an advancing cold front and associated cloud cover. Persistent rain and high humidity limit radiative cooling, while variable winds from the northwest to northeast could either enhance or suppress temperature drops. Historical October minima average near 17 °C, but this season’s elevated moisture from the developing El Niño pattern favors milder readings. Traders appear evenly split because ensemble spreads remain wide and new 00z/12z runs expected within 24 hours could shift the consensus by 1–2 °C.