Will I be cold?
Will I be cold in Mexico City in December?
Verdict
Maybe — Chilly at times.
Lows near 45°F — cool mornings and evenings, comfortable afternoons. Big diurnal swing (26°F) — layers matter more than one warm coat.
Day vs. night
Day
71°F
Comfortable
A T-shirt and a light overshirt is enough.
Night
45°F
Cold
Cold enough that a hat and gloves become mandatory.
Why
Mexico City in December averages highs of 71°F, lows of 45°F, 3 rainy days.
Layering wins here. A packable puffer plus a base layer handles the cool end without overheating in the middle of the day.
The day-to-night temperature swing is 26°F, which is the real story here — the average number hides how different midday and midnight feel.
See a full outfit plan for chilly evenings →
Mexico City in December outfit ideas from ForecastStyle.