In this work, a sensitivity study of the downstream wakes produced by wind turbines for different stability regimes in the atmospheric boundary layer is presented. The analysis is made on an extensive measurement data set of one of the largest onshore wind farms located in the Patagonian region of Argentina. Data from periods before the construction and during production of the park are analyzed. The novelty of the approach is the analysis of the negative wake impact on production and its dependence on the different stability regimes in the day and seasonal cycles. The outcomes coincide with the trends reported by other authors, finding a notable decrease in the wake impact during unstable conditions. The smallest impact is found during the summer at midday hours, when typically unstable conditions appear. On the contrary, during stable conditions, which generally occur at night, the impact is higher. The typical behavior of the park is in general close to the neutral condition.