"México is more than a desert between two beaches. México is a vast country and colonial México is seldom hot, even in the summer. That's the mistake most people make when they talk about summer in México, when they only know the beach resorts. 

"Many who have never been to México, or have only traveled to Cancun or the beach resorts have misconceptions about the weather in México. They are often heard to say," I wouldn't go to México in the summer -- too hot." Nothing could be farther from the truth, as most Texans will tell you. Everyone knows winter is fine almost anywhere in México, but don't know that it can get freezing or in the 40's in México City, Morelia, Toluca and sometimes even San Miguel de Allende. People live, work and retire in México because of the weather. San Miguel de Allende,Guanajuato, Cuernavaca, Oaxaca, Lake Chapala, Guadalajara, Morelia, Cuernavaca or anywhere in colonial México are just fine in summer.

México Weather By Seasons -- 3 Yes's or No's Means Pretty Intense. 1 Means Bearable.

Cities/Areas	Moderate Winter	Cold Winter	Hot Summer	Moderate Summer
Acapulco & South Pacific Coast	Yes	No	The Devil Summers Here	No, No, No
Alamos, Kino Bay	Yes	No	The Devil Summers Here	No, No, No
Cancun & Mayan Riviera	Yes	No	Yes for some, nice nights	Yes
Chihuhua	No	Yes	The Devil Summers Here	No
Cd. Victoria, Cd. Valles	Yes	No	Yes	No
Cuernavaca	Yes	No	No	Yes
Guadalajara, Lake Chapala	Yes, Yes, Yes	No, No, No	No, No, No	Yes
Mazatlan	Yes	No	Yes	No
México D.F.	Generally, some cold days	No	No	Yes
Monterrey	Generally, some cold days	No	Yes, Yes, Yes	No, No, No
Morelia	Generally, some cold days	No	No, No, No	Yes
Oaxaca	Yes, Yes, Yes	No, No, No	No, No, No	Yes
Pto. Penasco	Yes	No	Not by Arizonan standards	Yes
Pto. Vallarta, Manzanillo	Yes	No	The Devil Summers Here	No
San Luis Potosi	Yes	No	Yes, Yes, Yes	No
Saltillo	No	Yes	No, No, No	Yes
San Miguel de Allende, Guanajuato	Generally, some cold days	No	No, No, No	Yes
Tamazunchale	Generally, some cold days	No	No, but it can get in the 90's	Yes, but humid
Veracruz & Gulf Coast	Yes	No	Yes, Yes, Yes	No
Zacatecas	No, No, No	Yes, Yes, Yes	No, No, No	Yes, Yes, Yes