This minimum processed-data deposit contains key GeoTIFF outputs supporting the reported comparison of seasonal regime classifications and reliability/probability outcomes under a fixed 100 mm storage representation and SoilGrids-derived water-holding-capacity representation. Included spatial products comprise regime classifications, regime reliability surfaces, probabilities of one season and two-or-more seasons, scenario class-change surfaces, and the common-valid and no-data/water/unclassified masks required for interpretation. Raw external source datasets and large daily processing intermediates are excluded.