Cities are particularly vulnerable to climate change, which continues to drive rising air temperatures. The morphology of a city also influences local climate through diverse surface properties and configurations, leading to varying responses to increasing air temperature trends. This study examines the impact of climate change on Santiago, Chile, a city in a valley characterised by a semi-arid climate. We analysed near-surface air temperature and rainfall data measured by the Chile Bureau of Meteorology stations sited in three different local climate zones (LCZ) over the last 63 years. The three LCZs were localised in the peri-urban, inner-city and residential areas. The methodology was conducted with regression analysis, a seasonal time series model, and standardised anomalies to assess temperature and rainfall trends. The results indicate a higher rate of warming and a greater decline in precipitation in the peri-urban area compared to the inner-city and residential areas, in addition to a doubling of the warming rate in recent years. The daily temperature range (DTR) exhibited a negative trend in the peri-urban area but a positive trend in the inner-city and residential areas, reflecting differences in the warming rates of maximum and minimum temperatures. Additionally, the peri-urban area displayed significant intra-annual variability in temperature and rainfall within the seasonal cycle. However, smaller temperature changes at the beginning of the study period were presented in the peri-urban area but much larger ones towards the end, in contrast to the other areas. Our findings underscore the accentuated impact of climate change in the peri-urban area due to its permeable surface characteristics without vegetation, compared to the areas dominated by impermeable surfaces with or without vegetation. It highlights the importance of analysing urban air temperatures based on LCZs, challenging the conventional urban-rural temperature difference paradigm that underpins urban heat island assessments.