This dataset contains *.rdata files that contain model objects returned from the glm{stats} function (v.3.3.0) in R. for 258 models derived for selected wells in the conterminous United States. The models are generalized linear models with a binomial response variable (glm family set to binomial) for forecasting the probability of groundwater levels declining or maintaining below specified low thresholds for any time of the year for forecast time horizons from 1 to 12 months.