One of the popular methods to estimate the depth of surface runoff for a given rainfall is the Soil Conservation Service Number (SCS-CN) method. In this method, variation of antecedent moisture condition (AMC) is not continuous.
Links:
[1] http://admin.indiaenvironmentportal.org.in/feature-article/generalization-relationship-between-antecedent-moisture-and-antecedent-rainfall-scs
[2] http://admin.indiaenvironmentportal.org.in/category/journal/water-energy-international
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/rainfall
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/soil-resources
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/watershed-development
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/water-resources