Nocturnal cooling during frost events in complex terrain is governed by interactions between topography and boundary-layer processes, yet these dynamics remain poorly resolved at high temporal resolution. Here, we use high-frequency (10–15 min) thermal infrared observations from GOES-16 to characterise the spatial organisation of nocturnal cooling during a frost event in the Uco Valley (Mendoza, Argentina). We derive brightness temperature minima (BTmin), cooling magnitude (ΔT), and maximum nighttime cooling rates (MNCR), and identify two coherent thermal regimes. Colder and more intense cooling (BTmin = − 5.00°C; ΔT = 6.25°C; MNCR = 2.17°C h⁻¹) occurs over flat terrain, whereas weaker cooling (BTmin = − 2.52°C) is associated with more heterogeneous and sloped areas. Our results show that slope exerts a stronger control than elevation, and minimum temperatures are not systematically associated with topographic low, consistent with enhanced atmospheric decoupling and radiative heat loss over low-slope surfaces. These findings demonstrate that terrain configuration governs the spatial structure of cooling extremes at landscape scale, and that high-frequency geostationary observations provide a new capability to resolve these dynamics. The identified mechanisms have direct implications for frost occurrence in agricultural systems and other cold-air pooling environments.