Beet leafhoppers (Circulifer tenellus Baker) have been identified as the vector for a plant-pathenogenic phytoplasma known as beet leafhopper-transmitted virescence agent. Beet leaf-hopper-transmitted virescence agent causes purple top disease in potatoes, which can reduce yields and tuber quality. A trapping network, composed of ≈100 sites, monitors leafhoppers in the Columbia Basin of Oregon and Washington through a collaborative effort of regional researchers and stakeholders. Yellow sticky cards were used to determine the timing and spatial distribution of beet leafhoppers in the Columbia Basin; insects were counted weekly from early April through late October in 2006, 2007, and 2008. Weather data collected from a network of weather stations in Oregon and Washington were used in a nonparametric multiplicative regression analysis to determine which abiotic environmental variables might influence beet leafhopper populations. Weather conditions (mean temperature, dew point, precipitation, and wind speed) for 2006–2008 were also characterized using CIs established based on weather data from 1998 to 2004 for each weather variable. Several abiotic environmental factors significantly correlated with beet leafhopper populations, including temperatures the preceding fall and winter, elevation, and precipitation. Beet leafhopper populations appear to be highly variable across the region, with low numbers at a majority of the sites and only a limited number of high populations in localized areas.