Climate Mexico
Split in two by the Tropic of Cancer, Mexico is a country rich in transitions and contrasts. The second driest region on the continent (after the Atacama Desert in Chile) is located here: the Altar Desert in Sonora receives less than 100 mm of precipitation per year; but the rainiest region is also located here: north of the equatorial line, in the Grijalva Basin in Usumacinte, which receives more than 5 m of precipitation annually. Due to the differences in latitude and altitude, there is a great variety of microclimates in Mexico. Nevertheless, there are three main natural clusters: the South and the coastal fringes, tropical and humid; the semi-arid North, hot and dry; and the mountainous and volcanic Centre, mild or cool depending on altitude. The regions of both coasts are also susceptible to hurricanes and tropical storms.
The weather over the months
Mexico's climate offers excellent conditions for a year-round visit, whatever the season. The country offers a wide variety of climates, with average temperatures remaining mild. Altitude, latitude, distance from the ocean and the location of mountains in relation to prevailing winds are all factors that explain why different types of climate coexist in this vast country. Tropical zones are found in the south (the entire Mayan region), on the Pacific coast and along the Gulf of Mexico. The entire central part of the country is at high altitude, which means cooler evenings and nights. The north is semi-desert and desert, hot and dry. Everywhere, days are temperate or hot, depending on the season, thanks to the omnipresent sun. In Mexico, the passage of the seasons is not as marked as in other parts of the world; 93% of the national territory experiences temperatures that oscillate between 10 and 26°C. In winter, the temperature drops almost everywhere, but it's only really cold in certain mountainous regions. In fact, as in many tropical countries, a distinction is made between the dry season, from November to May, and the rainy season, from June to September. During the rainy season, it rains heavily almost everywhere in the country, but the showers are generally relatively short, lasting no more than half a day. You can visit Mexico in any season, as the climate varies from region to region, but the most popular periods are January to May and October to mid-December. On the other hand, if you're going to Mexico with the sole aim of sunbathing on the beach, it's good to know that the country is vulnerable to the vagaries of hurricanes from July to October. During this season, hurricanes can be devastating, particularly on the Gulf Coast, but also along the Pacific, as demonstrated by Hurricane Otis in October 2023, which devastated the Acapulco region.
The humid tropical South
The tropical climate zones cover the states of Campeche, Yucatán and Quintana Roo, which make up the Yucatán Peninsula; the plains of Chiapas on the border with Guatemala; and the Isthmus of Tehuantepec, which is the narrowest part between the Gulf of Mexico and the Pacific Ocean. This region has a warm and humid climate all year round, with temperatures above 17°C even on winter mornings. According to Köppen's climate classification, most of the Yucatán Peninsula has the characteristics of a "tropical savannah" climate, with two distinct seasons - dry and wet. A relatively dry winter is to be expected, despite the cool wind from the north, and heavy rainfall during the rainy season, which brings its share of tropical storms each year. The climate is fairly uniform throughout the three Mexican states of the peninsula. Some variations however, between the littoral giving on the Gulf of Mexico (States of Campeche and Yucatán), and the Eastern coast, giving on the Caribbean Sea (Quintana Roo). The peninsula can be explored at any time of the year, but some months should be avoided if you are afraid of the heat. The rainy season and certain times of the year when tropical storms can occur should also be taken into account when planning a trip. The plains of Chiapas, the state of Tabasco and the southeast of Oaxaca have a humid tropical climate with abundant rainfall year round. There is no real dry season in this region, so it is best to pack a k-way, no matter when you visit.
The Mountain Centre
Mexico is a mountainous country: 42% of its surface is above 2,000 meters. In the central part of the country, temperature variations are due to altitude. The temperate zones, or Tierra Templada, are above 800 meters and up to about 2,000 meters. Most farms are located in this region, as well as one of the country's largest cities, Guadalajara. Mexico D.F., the huge capital, is located on a plateau with an average altitude of 2,400 meters. It has a subtropical climate, with pleasant temperatures all year round. In winter, they range from 6°C at night to 21°C during the day. Temperatures rise gradually in spring, rarely exceeding 27°C, and then fall again from June onwards, when the rainy season begins. Until October, heavy rainfall is to be expected, usually in the afternoon and lasting only a few hours. Technically, Mexico D.F. is part of the Tierra Fría, the cold lands that lie at an altitude of over 1,800 m. Even higher, from 3,600, are the frozen lands, Tierra Helada. Here nothing grows, the mountains are covered with snow all year round. In these hostile lands, there is a great difference in temperature between day and night.
The semi-arid north
A vast arid and semi-arid zone covers the north of the Mexican territory on more than 1 million km², between the Tropic of Cancer and the border with the United States. There are two main deserts in this region: the Sonoran desert in the west, which occupies part of the state of Sonora and most of the Baja California peninsula; and the Chihuahuan desert, the largest in North America, which extends to the state of Zacatecas, crossed by the Tropic of Cancer. Both straddle the United States and Mexico. The climate in this region is hot and dry year-round, although it varies with latitude. The Baja California Peninsula and the Sierra Madre Occidental experience a more or less intense monsoon period from July to October. In these regions, which experience rainfall during the summer months, the climate is not desert, but semi-arid. The climate of northern Mexico is not very suitable for agriculture; few people live in these regions, most of the population being settled in the temperate zones of the center.
