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Understanding the moisture distribution pattern and associated suction variability of soil in response to environmental loading (e.g., precipitation, temperature) is important. However, there is a lack of understanding of the spatial variability of moisture and suction in different final cover systems. In this study, the spatial correlations between soil moisture and suction data from field instrumentation are examined using Spearman’s rank correlation test of three different types of landfill final cover systems: evapotranspiration (ET) cover, conventional clay cover, and engineered turf cover, under identical atmospheric conditions. In addition, box and whiskers plots were used to investigate the distribution of the field-measured data under environmental fluctuation. As observed from the box plot, soil moisture displayed maximum spatial heterogeneity in clay cover and very less in the engineered turf cover under identical environmental conditions. The ET cover exhibited a very strong spatial correlation of moisture and suction as indicated by the highly significant Spearman’s rank correlations (rs) ranging from −0.88 to −0.93. The clay cover showed a strong to moderate correlation (−0.51 < rs < −0.74) between the spatial distribution of moisture and suction. On the other hand, the engineered turf cover displayed poor agreement of the spatial moisture-suction distribution implying the soil under the engineered turf is relatively non-responsive under environmental variability compared to clay and ET cover. The preliminary findings from this study showed engineered turf’s capacity to maintain more moisture stability of the turf under the humid subtropical climate than other landfill covers.