Recent model consensus from sources including the Mexican National Meteorological Service points to a strengthening northerly flow and widespread rain across the Valley of Mexico on October 16, supporting overnight radiative cooling under overcast skies and elevating the chance of a minimum near or below 10 °C. Mexico City’s 2,240 m elevation amplifies sensitivity to these advection patterns, with current runs showing lows clustering 11–13 °C yet allowing for localized colder pockets if winds remain light. This scientific setup—cooler air mass arrival plus high humidity and precipitation—underpins the market’s elevated implied probability on the 7 °C-or-below bucket while leaving room for upward revision should the latest evening forecast shift warmer.