Flers, nestled in the heart of Normandy, France, occupies a geographically significant position within the Orne department. Located at approximately 48.75°N, 0.56°W, the town sits on a gently undulating plateau, part of the broader Norman countryside, characterized by a mix of agricultural land and scattered woodlands. The elevation averages around 180 meters above sea level, contributing to localized microclimates and influencing air circulation patterns. Flers is surrounded by a predominantly rural landscape of rolling fields, primarily used for dairy farming and cereal cultivation – a typical feature of the region. The town itself exhibits a classic Norman urban character, with a historic core featuring traditional half-timbered buildings and a market square, gradually transitioning into more modern residential areas. While not directly adjacent to a major river, Flers benefits from proximity to the River Orne, approximately 15 kilometers to the east, which can influence humidity levels and local weather systems. The town’s location is relatively distant from major industrial belts, situated between the larger urban centers of Caen and Le Mans. This distance generally shields it from the most severe industrial pollution, however, agricultural practices, particularly the use of fertilizers and machinery, and occasional burning of agricultural waste, can contribute to localized air quality concerns. The urban-rural gradient around Flers is gradual, with small villages and farms seamlessly blending into the town's periphery, impacting regional air flow and pollutant dispersal.

Flers experiences a temperate maritime climate, significantly impacting its air quality throughout the year. Spring (March-May) typically sees a gradual improvement in air quality as temperatures rise and vegetation begins to flourish, absorbing some pollutants. However, this period can also be marked by occasional episodes of pollen-related air pollution, affecting those with allergies. Summer (June-August) generally offers the best air quality, with consistent breezes dispersing pollutants and higher temperatures promoting atmospheric mixing. The relatively low population density and limited industrial activity contribute to this favorable period. Autumn (September-November) presents a more complex picture. As temperatures cool, the potential for temperature inversions increases, trapping pollutants closer to the ground, particularly during still, foggy mornings. Agricultural activities, including harvesting and the potential for field burning, can also elevate particulate matter levels. Winter (December-February) often witnesses the poorest air quality. Cold, stable air masses frequently lead to temperature inversions, exacerbating the effects of domestic heating (primarily wood-burning stoves, common in the region) and trapping pollutants. Fog, a frequent occurrence during winter, further reduces visibility and concentrates pollutants. Sensitive groups, including children, the elderly, and individuals with respiratory conditions, should exercise caution during these periods, limiting outdoor exertion and monitoring local air quality information. Avoiding outdoor activities on days with dense fog or stagnant air is advisable. The prevalence of agricultural land surrounding Flers means that seasonal agricultural practices significantly influence air quality, with peak activity impacting pollutant levels.