🇲🇽Mexico

Mexico spans 14°33′–32°43′N as a vast (approximately 1,964,375 km²) North American country between the United States and Guatemala/Belize, with a 9,330 km coastline on the Pacific (Gulf of California, Pacific proper) and the Atlantic (Gulf of Mexico, Caribbean).

Dramatic topography crossed by the Tropic of Cancer produces an extraordinary climate spectrum. It spans the Sierra Madre Occidental in the west and Sierra Madre Oriental in the east flanking the high Mexican Plateau (Mexico City at 2,250 m), the Sierra Madre del Sur, the volcanic Trans-Mexican Belt with Pico de Orizaba at 5,636 m (the country's highest peak and North America's third-highest), the lush Yucatán Peninsula, the Sonoran and Chihuahuan deserts, and the lush Selva Lacandona of Chiapas.

Hot desert (BWh) dominates Sonora and Chihuahua, semi-arid climates (BSh and BSk) cover much of the northern plateaus, humid subtropical (Cwa / Cfa) appears in parts of the interior and the northeastern lowlands, tropical savanna (Aw) spreads across the Pacific west coast, Yucatán and much of the Gulf coast, tropical rainforest (Af) and tropical monsoon (Am) occur in the wettest lowlands of Tabasco and Chiapas, subtropical highland (Cwb) defines the central plateau (Mexico City), and alpine tundra (ET) caps the highest volcanic peaks.

Mexico City sees highs of 22°C and lows around 9°C in January and highs of 27°C and lows of 14°C in May with 850 mm rainfall concentrated in wet season May–October. Cancún records highs of 29°C in January and 34°C in July with 1,300 mm; Veracruz 25°C and 31°C with 1,560 mm; Monterrey 22°C and 36°C with 670 mm; Mexicali 21°C and 43°C with only 70 mm, with record highs above 50°C.

Major events include Hurricane Otis (October 2023, Category 5, Acapulco), Hurricane Patricia (October 2015, strongest Pacific hurricane on record), Hurricane Wilma (October 2005, Category 4 at landfall near Cancún), and the severe 2022 drought that cut Monterrey's water supply. The 2024 heatwave saw Mexico City set a record of 34.7°C. Iztaccíhuatl's Ayoloco glacier has been declared extinct.

Our archive covers 144 Mexican cities with daily ERA5 reanalysis data going back to 1940. The hottest July afternoons are in Mexicali, with average highs around 42.5°C, while Cuauhtémoc has the coldest January nights, with average lows near 0.4°C. Comparing the last decade against the 1940–1970 baseline, mean temperatures across these cities have risen by about 1.8°C.