Temperature-induced geometric errors in manufacturing processes are a critical challenge for ensuring high precision of machined parts. These errors are largely influenced by the thermal behavior of machine components during operation, such as machine beds, travelling columns, fixtures and spindle units. This study presents the development and integration of an in-process temperature measurement system designed to monitor the thermal conditions of a machining center during the manufacturing process operated in a real production environment. The system incorporates temperature sensors placed in key areas of the machine tool structure, capturing the temperature field that impacts the machine tool components directly. The focus is put on the system's design, including sensor placement, wiring, data acquisition, and the integration of performance data gathered from the CNC such as spindle speed, feed rates and axis drive power consumptions. The data acquisition is supported by a post-process measurement of a geometrical feature on the machined workpieces. In a first step, the collected temperature and machine performance data are analyzed to identify patterns that contribute to the predication of thermal distortions, resulting in a geometric error. These results show a significant enhancement of machining accuracy and offer a promising methodology in precision machining for improving spatial thermal process stability by enabling adaptive control based on real-time thermal compensation feedback.