With the growth of renewable energies, particularly solar photovoltaic (PV) technology, driven by the progressive decline in PV module costs, support structures now account for an unprecedented share of the total cost of PV systems. Understanding how different meteorological phenomena influence the thermal behaviour of such structures is particularly relevant given that many of these systems are installed in regions where high solar irradiation, large thermal amplitudes, and extreme temperatures are prevalent. Furthermore, it has been proven that a good fit between specific climatic factors of site installation and support structure design and material selection can extend the system lifespan. Moreover, there is evidence that PV support structures may expand and warp due to heat waves and extreme temperatures, posing a serious risk to such systems. Despite this, PV support structures remain insufficiently investigated. Accordingly, this work aims to deepen the understanding of PV support structures, with an emphasis on cold-formed thin-walled (CFTW) steel profiles commonly used in Portugal in large-scale ground-mounted installations. A two-dimensional numerical model of a representative CFTW steel profile is developed, and the impact of extreme climatic factors on its thermal behaviour is analysed using finite element models (FEM) implemented in Abaqus, complemented by computational fluid dynamics (CFD) analyses. Furthermore, the effects on structural integrity are assessed. The results are expected to lay the groundwork for future analyses and contribute to design optimisation, ensuring greater durability, safety, and system efficiency under high-solar-exposure conditions.