Anyone know where I can get a KML of US urban areas with a population of 15k+?
not without doing some legwork. you can stitch that together from us census data– albertAug 5, 2016 at 16:13
Doesn't geonames.org have something like this (for all cities over a given site and then reduce to just USA), or are you asking something different? Polygons?– user3856Aug 6, 2016 at 23:43
Have you see Natural Earth Data Urban Areas? You can convert the .shp file to .kml with
ogr2ogr -f KML ne_10m_urban_areas.kml ne_10m_urban_areas.shp.
Not sure about the population sizes that mark these as "urban" areas.