Climatological means for Mexico City in late April consistently peg high temperatures near 27°C, often seeing peaks above 30°C under typical ridge patterns. A 20°C high implies a significant -7°C anomaly from the mean, demanding an extreme, unseasonable cold air advection or persistent, low-level stratus deck that current GFS/ECMWF long-range ensembles do not support. The diurnal temperature range alone typically pushes highs well past this threshold. Sentiment: Any whispers of a passing front are rapidly absorbed. This is an over-weighted low-probability event. 98% NO — invalid if a major, unforecasted upper-level trough establishes over central Mexico by April 27th.
Climatological means for Mexico City in late April consistently peg high temperatures near 27°C, often seeing peaks above 30°C under typical ridge patterns. A 20°C high implies a significant -7°C anomaly from the mean, demanding an extreme, unseasonable cold air advection or persistent, low-level stratus deck that current GFS/ECMWF long-range ensembles do not support. The diurnal temperature range alone typically pushes highs well past this threshold. Sentiment: Any whispers of a passing front are rapidly absorbed. This is an over-weighted low-probability event. 98% NO — invalid if a major, unforecasted upper-level trough establishes over central Mexico by April 27th.
