Volatilization of pesticides can detrimentally affect the environment by contaminating soil and surface waters many kilometers from where the pesticides were applied and intended. To improve quantifying the effect of soil moisture and meteorological interactions on pesticide volatilization, metolachlor vapor concentrations were continuously measured at two locations for 120 hours after application using polyurethane foam plugs for two consecutive years. A flux gradient technique was used to measure volatilized concentration profiles (each profile monitored at 0.3, 0.6, 1.2, and 1.95 m above the soil surface) combined with turbulent fluxes of momentum, heat and water vapor (eddy covariance) to estimate a pesticide flux diffusivity. This approach allowed for continuous measurements of metolachlor flux losses. The two locations were 90 m apart having similar soil texture properties and under identical crop management, but differ in surface soil moisture conditions. One location receives supplemental water from subsurface flow pathways as confirmed with ground-penetrating radar. Extensive soil moisture monitoring from both locations indicates that the wetter location has 40 to 60 % high water contents than the other. Although peak metolachlor volatilization losses for each year occurred during the first 24 hours after application, the wetter location had metolachlor vapor losses that were almost twice that of the drier location. Cumulative vapor losses for 2004 show that the wetter location lost 32,108 µg metolachlor m^-2 compared to 18,717 µg m^-2 for the drier location. During 2005, the wetter location volatilized 15,194 µg metolachlor m^-2 compared to 7,246 µg m^-2 for the drier location. These results indicate that surface soil moisture is a critical factor influencing pesticide volatilization and will need to be characterized if pesticide volatilization fluxes are to be accurately quantified and eventually modeled.