Trade-wind clouds exhibit a large diversity of spatial organizations at the mesoscale. Over the tropical western Atlantic, a recent study has visually identified four prominent mesoscale patterns of shallow convection, referred to as flowers, fish, gravel, and sugar. We show that these four patterns can be identified objectively from satellite observations by analyzing the spatial distribution of infrared brightness temperatures. By applying this analysis to 19 years of data, we examine relationships between cloud patterns and large-scale environmental conditions. This investigation reveals that on daily and interannual timescales, the near-surface wind speed and the strength of the lower-tropospheric stability discriminate the occurrence of the different organization patterns. These results, combined with the tight relationship between cloud patterns, low-level cloud amount, and cloud-radiative effects, suggest that the mesoscale organization of shallow clouds might change under global warming. The role of shallow convective organization in determining low-cloud feedback should thus be investigated. Plain Language Summary Satellite imagery shows that clouds in the trade-wind regions exhibit a large diversity of patterns. Over the tropical Atlantic close to Barbados, the population of low-level clouds can organize in different ways, adopting patterns evocatively referred to as "flowers","fish" ,"gravel," and "sugar." This study shows that these different patterns, originally identified subjectively, can be recognized more objectively from space measurements of infrared radiation. It also shows that the relative occurrence of these different patterns relates to the strength of the trade winds near the ocean surface and to the stability of the lower atmosphere. Finally, it shows that each pattern is associated with a different cloud amount and thus impacts the radiative cooling of the Earth differently. These results suggest that under global warming, the change in environmental conditions might perturb the frequency of different patterns, which might affect the Earth's radiative response to warming in a way that has not been previously considered.