Upland accessibility for nesting Mallard, Northern Pintail, Blue-winged Teal, Northern Shoveler, Lesser Scaup and Gadwall was predicted by combining the distance a hen will travel from a core wetland to upland nesting cover, and the distribution of breeding duck pairs predicted using a duck pair - wetland relationship that is dependent on wetland size, type, and geographic location. Wetland percent full adjustments for individual wetlands are made when models are available. Annual field observations on 3000+ wetlands from 1987-2021 were used to develop the duck pair – wetland relationships and 3,000,000+ individual wetland basins were modeled and duck pairs were predicted for each wetland. The land area was subdivided into roughly 40 acre units and the accessibility of each unit was modeled using a moving focal window relative to species- specific travel distances. This product was named the "thunderstorm map" because it looks like a radar of a thunderstorm moving across the prairie