Climate - Determine Your Ideal
Your climatic requirements may differ from mine, but if you're reading this you're probably not considering Alaska as a retirement choice. Most people's concept of the ideal climate for retirement living involves warm temperatures, and Mexico can provide them.
Whatever location you're considering, make sure you visit it at least three different times of the year and for at least a week or longer each time. Do your research. Consult weather websites for the weather history of your retirement destination. Track or chart the average, low and high temps, rainfall, etc. Don't forget to consider humidity, wind and other climatological aspects of outdoor/indoor comfort. The end of the rainy season may mean the beginning of the mosquito season.
Your retirement climate research should also include speaking with native and/or year round residents. If there is a long dry season, the last month or so may be particularly dusty. Certain times of the year may be foggy in inland valleys or along the Pacific coast. Have you ever been to San Francisco in July? Only the tourists are wearing shorts. While occasionally there is a hot spell in the Bay Area then, it's the hot (normal) summers in the Central Valley that drawn in the ocean fog. The valley finally cools down in late September, making the best weather occur in October. How about Portland, Oregon? I once spoke with a Mexican who had lived there for six years working as a union carpenter. He described the city has having two seasons - August and rainy.
Merida, in the state of Yucatan, is often described as the Paris of Mexico, but you won't mistake the climate for France's. Hot, sticky, humid. A lovely place to visit, but it's not my retirement choice. However if you grew up in Houston, it might be pretty tolerable. That's why it's important to visit, visit again and then revisit.