Four (spring, summer, fall and winter), just as the rest of the world has.
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not true. some countries have 2 seasons,a rainy and a dry season.
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Which are of course, part of the summer and winter seasons.
two a rainy and dry season.
Yes. There are regions with extensive cloud cover, depending on season and latitude.
Subtropical
The Christmas season in Mexico is celebrated from December 3 to January 6. One can learn more about the traditions surrounding the holiday season on TLC.
Mexico is also on the Northern hemisphere, so it will be Spring in Mexico when it is spring in the US.
Autumn or fall.
The season officially started on May 15 in the eastern Pacific, and on June 1 for the central Pacific, and will officially end on November 30, 2009.
It ends November 30, as it does everywhere else in the Atlantic Basin.
A one-way ticket from Denver to Mexico City would cost you from 350 to 450 dollars, depending on flight class, nonstop vs many stops and the season you are traveling on.
From twelve to thirteen, depending on the season.
Summer
Fall-Winter (season changes on December 20-21, depending on specific years).