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Botanical composition of grasses, forbs, and shrubs is strongly influenced by topographic position on the dunes on Sandhills rangeland. However, limited research has fully evaluated the influence of weather factors (e.g., spring precipitation and growing degree days) on herbage production of different functional groups at the topographic position scale. From 2000 to 2015, herbage production data, separated by cool- and warm-season grasses, forbs, sedges, and shrubs, were collected from dune top, north-facing slope, south-facing slope, and interdune topographic positions in the eastern Nebraska Sandhills. To evaluate the influence of current and previous year weather factors on herbage production, stepwise regression models were developed for each functional plant group and total plant production at the different topographic positions. Regression models explained a large range of variation in herbage production of different functional groups at different topographic positions (0.04 < r2 < 0.63, P< 0.05). Regression models for total herbage production in August were the most consistent across topographic position and were influenced positively by growing season precipitation events and spring+summer precipitation and negatively by growing degree-days (r2=0.48 to 0.5, P < 0.01). This was likely related to the influence of these weather factors on warm-season grass growth from June to August. While regression models did not explain a large amount of the variation for some functional groups, they did identify the major factors that influenced herbage production at different topographic positions and identified the most important weather-related factors that can be used to estimate annual herbage production on mixed-grass, Sandhills rangelands.