Impervious surface area (ISA) from the National Land Cover Database 2001 and land surface skin temperature from MODIS averaged over three annual cycles (2003–2005) are used in a spatial analysis to assess the surface urban heat island (UHI) signature and its relationship to settlement size and shape, development intensity distribution, and land cover composition for 42 urban settlements embedded in forest biomes in the northeastern United States. Development intensity zones, based on percent ISA, are defined for each urban area emanating outward from the urban core to nearby rural areas and are used to stratify land surface temperature. The stratification is further constrained by biome type and elevation to ensure objective intercomparisons between urban zones within an urban settlement and between settlements. Stratification based on ISA allows the definition of hierarchically ordered urban zones that are consistent across urban settlements and scales. For cities within the northeastern US temperate mixed forest biome, we found that settlement size, shape, and development intensity significantly influenced the amplitude of summer daytime UHI. Our study indicates that for cities of similar size, the ISA density distribution within the urban area and the shape of the urbanized area as measured by area to perimeter ratio are significant modulators of UHI magnitude. Our results indicate that remotely sensed satellite data provide a consistent characterization of the UHI magnitude as well as its major drivers across regional scales.