Monterrey has a semi-arid climate with hot summers and mild winters. October to March is the most comfortable time to visit — daytime temperatures between 15 and 25°C, clear skies, and no humidity. This is also the best time for hiking in Chipinque or the Huasteca canyon.
Summer (May to September) is genuinely hot — temperatures regularly exceed 35°C and the city becomes humid during the rainy season (July to September). Thunderstorms are common in the afternoons. Avoid late summer if heat bothers you. Monterrey sits in a valley ringed by mountains that trap warm air, which makes the heat more intense than the latitude would suggest.