Monterrey in August

October through April gives you perfect weather — sunny days around 75°F and cool nights perfect for rooftop bars. December and January can get surprisingly chilly, so pack layers. March and April offer ideal conditions before the summer heat kicks in. May through September? Forget about it. Temperatures hit 100°F regularly, and the humidity makes walking outside feel like a punishment. The mountains trap heat and smog, creating an oven effect. But here's the thing — hotel rates drop dramatically in summer, and you'll have pools and air-conditioned attractions mostly to yourself. Just plan indoor activities between 11 AM and 6 PM.