What September feels like in Mexico City
September falls in Mexico City's wet season — the rainfall numbers rise clearly above the dry months. Daytime temperatures are mild — neither cold nor hot for walking around. Evenings bring a clear drop in temperature, and nights are cool. Humidity is on the high side, but mild temperatures keep it comfortable.
Rain in Mexico City in September
Dry days are the exception, with rain on most days. Rainy days are intense, averaging about 9.3 mm (0.4 in) — downpours rather than drizzle. That is heavier than Mexico City's usual 7.4 mm per rainy day across the year. It is among the three wettest months of the year.
Daylight and sunshine in September
In mid-September, sunrise is at about 6:24 am and sunset at about 6:40 pm (local time) — 12 h 17 min of daylight. Compared with mid-August, the day has lost 32 min. The sun is out for roughly 77% of those daylight hours, so there are plenty of bright spells.
How September compares to the rest of the year
September is the 3rd coolest month of the year in Mexico City. Afternoons run 0.7°C (1.3°F) cooler than in August, with about the same rain. Temperatures barely move from one month to the next here. The next month's average high: 21.4°C (70.5°F).
Who September suits
- Sightseeing: less ideal — rain falls on more than half the days.
- Parks & outdoor: less ideal — rain interrupts outdoor plans.
- Museums & indoor: a good choice — with rain on most days, galleries and museums make easy plans.
Tips for visiting Mexico City in September
Versatile Layers
Pack pieces you can take off by noon and put back on at dusk.
Rain Protection
A packable rain jacket saves the day on showery afternoons.
Sunglasses
Bright days make sunglasses worth packing.
Quick questions
How warm is Mexico City in September?
Expect around 21.3°C (70.3°F) in the afternoon and 12.4°C (54.3°F) at night, which most visitors would call mild.
Does it rain a lot in Mexico City in September?
Yes, fairly — rain falls most days and totals about 205 mm, so an umbrella is worth carrying.
What should I wear in Mexico City in September?
The numbers point to versatile layers, rain protection and sunglasses. Add a layer for after dark.
Is September or October better for visiting Mexico City?
October scores better on our climate ranking (#8 of 12 vs #10), rated Good against Fair. October has fewer rainy days.