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Kūstī, situated at 13.1700°N, 32.6600°E in Sudan's White Nile State, occupies a strategic position along the White Nile River, approximately 300 kilometres south of Khartoum. This riverine city lies within the vast Sahelian belt of Africa, characterised by flat to gently undulating terrain with an elevation around 380 metres above sea level, placing it within the transitional zone between the Sahara Desert to the north and the savannahs to the south. The urban area of Kūstī is linear and elongated, following the course of the White Nile, which serves as both a vital water source and a transportation corridor, with the city functioning as a key hub for river traffic and agricultural trade. Surrounding Kūstī, the landscape transitions from irrigated agricultural zones along the riverbanks—dominated by cotton, sorghum, and sesame cultivation—to semi-arid scrubland beyond, creating a distinct urban–rural gradient where dust from unpaved roads and agricultural activities frequently infiltrates the city. Proximity to the White Nile moderates local microclimates slightly but also contributes to humidity that can trap pollutants, while the absence of significant topographical barriers allows Saharan dust plumes to sweep across the region unimpeded. Kūstī's position within Sudan's agricultural heartland means that seasonal burning of crop residues and land clearance, combined with urban emissions from vehicles, generators, and domestic biomass burning, exacerbate particulate matter concentrations, particularly during dry periods when atmospheric stagnation prevails.

In Kūstī, air quality follows a pronounced seasonal rhythm shaped by the interplay of the Intertropical Convergence Zone (ITCZ) and local meteorological conditions. During the dry season from November to April, pollution peaks typically occur from December to March, when northeasterly Harmattan winds transport fine Saharan dust over vast distances, blanketing the city in a haze of particulate matter. These months are characterised by low humidity, minimal rainfall, and frequent temperature inversions at night that trap pollutants near the surface, making early mornings particularly hazardous for outdoor activity. Sensitive groups such as children, the elderly, and those with respiratory conditions should limit exposure during this period, especially on days with visible dust storms. The wet season from May to October brings relief, with the southwesterly monsoon winds ushering in moisture from the Atlantic, peaking in rainfall during July and August. This precipitation effectively scrubs the atmosphere of particulate matter, leading to cleaner air and improved visibility, making these months favourable for outdoor pursuits. However, high humidity can occasionally lead to fog formation, which may temporarily elevate pollutant concentrations by inhibiting dispersion. Transitional months like October and November see variable conditions as winds shift, with sporadic dust events possible. Health guidance emphasises monitoring local weather reports for dust advisories, using air purifiers indoors during peak pollution months, and scheduling vigorous exercise for late afternoons when mixing heights are higher.