Urbanization and the concurrent loss of green areas determine changes in land surface temperature (LST) and worsen the phenomenon of urban heath islands (UHI). To understand these relationships, long-term studies have been carried out using remote sensing data, analyzing the trend over a large area. This study is aimed at multi-temporal analysis based on satellite data for calculating LST and land use indices to identify their interaction with UHIs during the period 2000–2023, in the region known as Phlegrean Area, in Campania (Italy). Results reveal that the reference period was characterized by increasing LST which affected UHI share and intensity. On the other hand, we observed a contraction of greenery in favor of urban areas. Furthermore, in the same period of observation, it is noteworthy the loss of more than 3 km2 of forests due to a severe wildfire. In conclusion, the model results show that there could be a correlation between the increase in artificial surfaces and the increase in temperatures and consequently the enlargement of UHI areas. A greater attention in the design of green areas in urban contexts, considering sustainability and ecology targets, could help mitigating UHI phenomenon.