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Şabbāshahr, nestled within the Tehran Province of Iran, occupies a geographically complex position approximately 35 kilometers southwest of the capital city, Tehran. Located at coordinates 35.5817° N, 51.1119° E, the city sits at an elevation of roughly 1,850 meters (6,070 feet) above sea level, placing it within the Alborz mountain range's foothills. This elevated terrain significantly influences local weather patterns and, consequently, air quality. The surrounding landscape is characterized by a mix of semi-arid plains transitioning into rugged mountainous terrain, typical of the Iranian plateau. To the north, the Alborz mountains act as a barrier, often trapping pollutants and contributing to temperature inversions, particularly during the colder months. The urban–rural gradient around Şabbāshahr is relatively sharp; the city is bordered by agricultural lands primarily used for cultivating fruits and vegetables, and beyond that, more extensive rangelands. While Şabbāshahr itself is a relatively small city with a population of around 53,971, its proximity to Tehran and the broader industrial belt stretching along the Tehran-Karaj corridor means it is susceptible to transboundary pollution. The lack of significant bodies of water nearby limits natural air purification processes. The prevailing winds, often channeled through the mountain passes, can either disperse pollutants or concentrate them depending on their direction and strength, creating localized air quality variations. The city's layout, with a mix of residential and light industrial areas, further contributes to its unique microclimate and pollution profile.

Şabbāshahr's air quality experiences a distinct seasonal cycle heavily influenced by regional meteorology. Winter (December-February) consistently presents the most challenging conditions. Cold, stable air masses frequently settle into the Alborz basin, leading to persistent temperature inversions. These inversions trap pollutants close to the ground, exacerbating existing emissions from both local sources and transboundary transport from Tehran. Fog, common during these months, further reduces visibility and hinders pollutant dispersion. Spring (March-May) brings a gradual improvement as temperatures rise and wind speeds increase, though dust storms originating from the central Iranian deserts can occasionally impact air quality. Summer (June-August) generally sees the best air quality due to strong convective mixing, which disperses pollutants effectively. However, heatwaves can lead to stagnant air conditions and ozone formation. Autumn (September-November) marks a transitional period, with decreasing temperatures and increasing wind variability. The months of November and December are particularly concerning, as the combination of cooler temperatures and decreasing wind speeds often leads to a resurgence of winter-like pollution conditions. Sensitive groups, including children, the elderly, and individuals with respiratory conditions, should limit outdoor activity during winter mornings and days with visible haze. During the warmer months, avoiding strenuous outdoor exercise during peak afternoon heat is advisable. Public health advisories are often issued during periods of elevated pollution, recommending the use of air purifiers and masks.