WEATHER IN NORTHERN MEXICO...

BRIAN WRITES... Hey Jim, I always thought that the closer you get to the equator, the hotter the temperature. However, Mexico tends to be much more mild than here in Texas, even though Texas is more northern. What in the world is going on?


First of all, let us define our terms properly. When we refer to Mexico, we will be using weather data from Mexico City in southern Mexico. When we refer to Texas, we will use weather data from Austin, a town in northern Mexico as seen in the map of Mexico from 1851.

Latitude is only one of many factors that influence weather. Mexico is cooler than Texas only in the summertime. In the winter, Mexico is warmer. Let’s take a look at some average high temperatures for Austin and Mexico City.

Austin’s hottest months are June, July, and August with average monthly highs of 91, 95, and 96, respectively. Mexico City, on the other hand, has it’s hottest weather in April and May with monthly average highs of 79.

In the winter, Austin’s coldest month is January, with an average monthly high of 60, while Mexico City’s average monthly high is 70.

So Mexico’s weather is milder in all seasons. The reason for this is, besides latitude, major factors that influence weather are oceans, prevailing winds, and terrain. As Mexico city is closer to the Pacific in a latitude that has prevailing westerly winds, its temperatures are modified by the cool Pacific Ocean. Austin, on the other hand, is many miles from the Pacific and has much land and many mountains between it and the Pacific. Even though Austin may be close to the Gulf of Mexico, with the wind coming out of the west, the Gulf has little influence on Texas’s weather.

The same moderating affects can be seen when you compare weather in Europe with weather in North America. Paris, which has relatively mild winters is on the same latitude as International Falls, Mn., which has incredibly harsh winters. That is because Paris’s weather is greatly influenced by the warm Gulf stream that flows from the Caribbean, up the eastern seaboard of the U.S. then across the Atlantic from Virginia to Ireland. That was one of many factors that left the Pilgrims so il-prepared for such harsh winters when they arrived at New England. They had no way of knowing the winters would be so much harsher even though they were actually south of their homeland.