A distributed weather measurement system is developed at the Karlsruhe Institute of Technology for the efficient use of the maximum power capacity of high-voltage overhead lines. System-wide information allows Transmission System Operators to make the right choices when operating the grid. Therefore, the positioning of the weather stations for overhead line monitoring is of critical importance. In the ideal situation, one sensor node per electrical tower would collect more than enough data to understand the conditions in the locality of the line. However, the cost of this system is the limitation. To solve this, the so-called hotspots along the line can be identified and used as a minimal solution for a good and safe monitoring system. This identification process has to be automatic, fast and robust, in order to achieve a system-wide analysis of the electrical network in an acceptable amount of time. This article demonstrates and analyzes the results of such a process.