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Allende, Coahuila, Mexico, occupies a geographically significant position within the arid landscapes of northern Mexico. Situated at approximately 28.33° N, 100.83° W, and an elevation of roughly 1000 meters (3280 feet) above sea level, the city’s location contributes directly to its air quality challenges. The surrounding terrain is characterized by rolling hills and scrubland, typical of the Coahuila desert, with sparse vegetation and limited natural air filtration. Allende lies within the broader Monterrey metropolitan area's sphere of influence, though it retains a distinct, smaller-town character. This proximity to Monterrey, a major industrial hub, means Allende is susceptible to downwind pollution transport, particularly from steel production, cement manufacturing, and related industries. The urban–rural gradient shifts rapidly around Allende; the immediate periphery is agricultural, with fields of sorghum and corn, which can contribute to particulate matter during harvest seasons. Further out, the landscape transitions to extensive desert. The lack of significant bodies of water nearby—the nearest substantial river is a considerable distance away—limits natural precipitation and humidity, further exacerbating dust and particulate pollution. Topographically, the bowl-like shape of the valley in which Allende sits can trap pollutants, especially during periods of temperature inversion, hindering dispersion and leading to localized air quality degradation. The regional climate, dominated by high temperatures and low rainfall, further compounds these issues, creating conditions conducive to dust storms and stagnant air masses.

Allende’s air quality experiences a distinct seasonal pattern dictated by its arid climate and regional industrial activity. The dry season, typically spanning from March to June, presents the most significant air quality concerns. High temperatures and minimal rainfall create stable atmospheric conditions, frequently leading to temperature inversions where a layer of warm air traps cooler air (and pollutants) near the ground. This inversion effect, coupled with prevailing winds from the north and northwest, concentrates industrial emissions and dust from agricultural activities. March and April often see increased dust events due to wind erosion of exposed soil. The summer months (July-August) bring slightly increased humidity and occasional thunderstorms, which can temporarily flush pollutants from the atmosphere, offering brief periods of improved air quality. However, these relief periods are often short-lived. The transition seasons, September-November and December-February, are characterized by more variable weather patterns. Cooler temperatures and occasional rainfall can improve air quality, but periods of stagnant air and dust storms still occur. Sensitive groups, including children, the elderly, and individuals with respiratory conditions, should exercise caution during the dry season, particularly during periods of high dust or noticeable industrial odors. Limiting outdoor exertion during midday heat and avoiding areas near industrial facilities are advisable. Maintaining indoor air quality through filtration and ventilation is also crucial. The winter months, while cooler, can still experience temperature inversions, so vigilance is required year-round.