Mexico City’s late-September climate features typical daily highs around 23–25°C under the influence of the subtropical high-pressure system and regional moisture from the Pacific and Gulf, with model consensus from sources like the National Meteorological Service indicating limited warming potential on the 30th. Recent forecasts highlight overcast skies and a modest chance of afternoon showers that cap afternoon peaks near 26°C, aligning with the market’s strong preference for that threshold while leaving modest room for brief clearing that could push readings to 27°C or higher. Historical data shows rare exceedances above 26°C this time of year absent anomalous ridging, and current steering patterns offer no indication of such intensification before resolution.