WeatherJourney.com

San Cristóbal de las Casas weather by month: averages, rainfall & climate trends

Temperature-wise, the seasons in San Cristóbal de las Casas are gentle: monthly means drift only 3.8°C over the whole year. Rainfall is strongly seasonal: the bulk of the year's rain falls between May and October. San Cristóbal de las Casas weather by month: average temperatures, rainfall, extremes and how the climate has changed since 1940.

Today vs average

+0.6°Chigh near average

20° / 14°Today
20° / 11°Average
see today in detail →

How it's changed

+1.9°Caverage temperature, 2016–2025 vs 1940–1949average temperature vs 1940–4943days above 25°C a year now (2016–2025) · 6 in the 1940sdays above 25°C · 6 in the 1940s+1.9°C vs the 1940s · see how it's changed →
Weather by montha typical year, averaged over the full recordJanuary, rain 16 mmhigh 19°low 8°February, rain 14 mmhigh 21°low 9°March, rain 24 mmhigh 23°low 10°April, rain 61 mmhigh 24°low 11°May, rain 208 mmhigh 23°low 12°June, rain 448 mmhigh 21°low 12°July, rain 290 mmhigh 21°low 11°August, rain 326 mmhigh 21°low 12°September, rain 409 mmhigh 20°low 12°October, rain 203 mmhigh 20°low 11°November, rain 58 mmhigh 19°low 10°December, rain 23 mmhigh 19°low 9°wettest month June, 448 mm · 2,079 mm a yearsee month by month →

Right now

What it's doing today vs the historical average for this date.
Overcast

Right now

15.7°

14°feels like
84%humidity
13°dew point
17 km/hfrom NE
UV index1.4
sunrise06:04sunset17:45day length11h 41m
TodayOvercast20°14°
ThuOvercast20°14°
FriPartly cloudy20°13°
SatOvercast18°12°
SunOvercast19°12°
MonOvercast17°12°
TueOvercast20°12°

On this date: October 21

Today (forecast)
20° / 14°
Average for October 21
20° / 11°

High near average · +0.6°C

  • Highest since 1940: 23.3° · 2004
  • Lowest since 1940: 5.9° · 1952
  • One year ago: 21° / 13°

Every October 21 in history, coldest to hottest

▲ Daily highs▼ Daily lows

Dots show daily highs (top) and lows (bottom) for each October 21 on record (n = 87). Outlined dots are today's forecast.

Area we sample

Each city's history comes from one ERA5 grid cell, about 28 km across, shown by the dashed box. Near mountains or coasts, conditions can vary across the cell.

Location & data

Historical weather for San Cristóbal de las Casas is sampled from the ECMWF ERA5 reanalysis at 16.73°N, 92.64°W, with daily records since 1940.

Coordinates
16.73°N, 92.64°W
Time zone
America/Merida
Period
1940–2026
Data source
ERA5 (ECMWF)

Last 30 days

31 of the last 31 days were warmer than the historical average for that date. Average difference: +1.7°C.

Each bar is one day, from morning low to afternoon high. Warm-colored bars are days whose mean ran above average; cool bars ran below. The dot inside the bar is the daily mean. The shaded band is the typical 10–90% range expected for that date. Average = the day's mean temperature averaged across every year of record (1940–2026) for that calendar date.

This date over the years

One dot per year, showing the mean temperature on this calendar date. Dots are warmer or cooler than the long-term average (dashed line); the shaded band is the typical 10–90% range, and the highlighted dot is today's forecast. Based on ERA5 reanalysis: modelled estimates, not station readings.

Weather by month

Average temperatures and rainfall for each month: a typical year, from the full record.

Climate overview

The year peaks in April, at around 23.5°C by mid-afternoon, with nights around 11.2°C. In January, the coolest month, afternoons reach about 19.4°C and nights dip to 8.1°C. Frost is essentially unknown.

In total, San Cristóbal de las Casas averages about 2,079 mm of precipitation a year; June is usually the wettest month (448 mm) and February the driest (14 mm).

The record here starts in 1940, and since then the annual mean in San Cristóbal de las Casas has climbed 1.9°C from the first ten years to the last ten. Days above 25°C have grown noticeably more frequent, from around 6 a year in the first decade to about 45 in the last.

Climate graph (climograph)

April is the warmest month, January the coolest: a yearly swing of 4°C. Wettest month: June (~448 mm). Whole year averages ~2,079 mm of rain.

Bars = average monthly rainfall (right axis). Lines = average daily high and low (left axis). Average = each month's value averaged across every year of record (1940–2026).

Monthly wind

Average daily peak wind at 10 m, by month.

Monthly solar energy

Average daily incoming solar energy in megajoules per square metre: the record's own proxy for how sunny the month is.

San Cristóbal de las Casas month by month: what to expect

Typical conditions for each month, averaged across the full record (since 1940). Daylight is the time from sunrise to sunset. Highest and Lowest are the most extreme values in the ERA5 dataset (modelled since 1940), so they can differ from official weather-station readings.

MonthAvg highAvg lowRainDaylightHighestLowest
January19.4°8.1°16 mm11.1 h26.0° (2025)0.3° (1996)
February20.9°8.6°14 mm11.5 h27.1° (2007)0.4° (1998)
March22.6°9.9°24 mm11.9 h28.9° (2000)2.5° (2013)
April23.5°11.2°61 mm12.4 h29.9° (2024)3.9° (2003)
May22.7°12.1°208 mm12.8 h31.3° (2024)5.7° (1970)
June20.8°12.1°448 mm13.0 h28.2° (2024)8.5° (1971)
July21.0°11.5°290 mm12.9 h25.4° (2016)6.7° (1955)
August21.0°11.6°326 mm12.6 h25.4° (2015)7.8° (1959)
September20.1°11.8°409 mm12.1 h25.0° (2024)8.6° (1975)
October19.7°11.2°203 mm11.6 h24.3° (2014)4.6° (1943)
November19.3°9.7°58 mm11.2 h24.8° (2010)2.1° (2006)
December19.2°8.6°23 mm11.0 h24.9° (1987)0.3° (1945)

How it's changed

Year-by-year signals from 1940 to today.

Climate stripes

Annual mean shifted from 1940–1949 to 2016–2025 by +1.9°C.

Each vertical stripe is one year. Color encodes how much that year's annual mean differed from the long-term average. Average = each year's annual mean compared to the average of all years (1940–2026). cooler ← → warmer

Annual mean temperature

Long-term trend: +0.27°C per decade.

One point per year, showing the temperature averaged across the whole year. The dashed line is the least-squares long-term trend. Based on ERA5 reanalysis: modelled estimates, not station readings.

Seasonal warming

Sep–Nov is warming fastest: +0.29°C per decade.

Each faint line is one three-month period's average per year; the bold dashed line is its long-term trend. Different parts of the year often warm at different rates. Based on ERA5 reanalysis: modelled estimates, not station readings.

Hot days vs frost days

Days ≥ 25°C per year: 5.5 early in the record → 42.5 recently. Frost days: 0 → 0.

Thin lines are raw yearly counts; thick lines are the smoothed trend that removes year-to-year noise. The hot-day threshold is auto-picked per city so the line actually moves. Average = a centered 5-year rolling average to smooth weather noise.

Yearly hot & cold extremes

Hottest day since 1940 in 2024, coldest in 1945: 31.3°C / 0.3°C.

One point per year: the single hottest and coldest day recorded that year.

Annual rainfall

~2,079 mm/year on average. Last decade: +4% vs that average. Long-term trend: +53 mm per decade.

One bar per year of total rainfall. Dashed line is the long-term average. Average = the average annual rainfall across every year of record (1940–2026).

Day-by-day grid

Each tiny square is one calendar day across the full record, about 30,000 days per city. Use the mode switch above the chart: Anomaly colors each day by how far it ran from the historical average for that date (red = warmer, blue = cooler), Daily mean temp shows the absolute mean temperature for the day (useful to see seasons and heatwaves), and Precipitation shows daily rainfall (useful to spot wet/dry seasons and droughts). Average = the long-term average for that calendar date (1940–2026).

Frequently asked questions about San Cristóbal de las Casas

Which is the warmest month in San Cristóbal de las Casas?
On long-term average, the warmest month in San Cristóbal de las Casas is April (mean daily temperature of about 16.7°C) and the coolest is January (about 13.0°C).
How does today's temperature in San Cristóbal de las Casas compare to the historical average?
On October 21, 2026, San Cristóbal de las Casas is forecast to reach a high of 20.4°C and a low of 14.1°C. The long-term average for this date (the full record since 1940) is a high of 19.8°C and a low of 10.8°C, so today's high is 0.6°C warmer than that average.
How much has San Cristóbal de las Casas warmed since 1940?
Comparing the first decade of the record (1940–1949) with the most recent (2016–2025), the annual mean temperature in San Cristóbal de las Casas is about 1.9°C warmer.
How much does it rain in San Cristóbal de las Casas?
San Cristóbal de las Casas receives about 2,079 mm of precipitation per year on long-term average, with June typically the wettest month.
What is the average temperature in San Cristóbal de las Casas?
Over the full record (since 1940), the annual mean temperature in San Cristóbal de las Casas is about 15.0°C. The warmest month is April and the coolest is January.
What are the average temperatures in San Cristóbal de las Casas by month?
Average daily highs and lows for each month in San Cristóbal de las Casas (°C, full record since 1940): January 19°/8°, February 21°/9°, March 23°/10°, April 24°/11°, May 23°/12°, June 21°/12°, July 21°/11°, August 21°/12°, September 20°/12°, October 20°/11°, November 19°/10°, December 19°/9°.
What is the weather like in San Cristóbal de las Casas in summer?
June to August is summer in San Cristóbal de las Casas, and it is wet and mild. Afternoons run 21°C and nights 11–12°C; August is the warmest month. About 354 mm of rain a month. It is the wettest season of the year.
What is the weather like in San Cristóbal de las Casas in winter?
December to February is winter in San Cristóbal de las Casas, and it is dry and mild. Expect 19–21°C by day and 8–9°C at night, with January the coldest month. Rain eases through the season, 23 mm in December to 14 mm in February. It is the driest season of the year.
What is the weather like in San Cristóbal de las Casas in spring?
March to May is spring in San Cristóbal de las Casas, and it is pleasantly warm. Daytime highs sit at 23–24°C and nights at 10–12°C; April is the warmest month. Rain picks up through the season, 24 mm in March to 208 mm in May.
What is the weather like in San Cristóbal de las Casas in autumn?
In autumn, September through November, San Cristóbal de las Casas is wet and mild. Afternoons run 19–20°C and nights 10–12°C; November is the coldest month. Rain eases through the season, 409 mm in September to 58 mm in November.

Weather in nearby cities