The seasonal thermal effect of urban green space in an arid city (San Juan, Argentina) was studied by processing LANDSAT 5 TM+ multispectral satellite images for the year 2011. Air temperature was obtained using the TvX method on a broad sampling of relationships between the normalized vegetation index NDVI and surface temperature. Thermal data was combined with meteorological records from a weather station located in the city center. This information was quantified and related to the city's urban characteristic bands and the seasonal heat island, the latter of which was obtained by processing the same 2011 satellite images. The results validate and expand those obtained from previous in situ fieldwork regarding the bioclimatic effect of green space in arid urban environments. Lastly, the efficiency of the use of remote sensing for urban studies whose results can be applied to bioclimatic urban design is verified.