Originally Posted by
sectordirector
However with 1/8 mile visibility and no surface radar, there was no way for the tower to observe that.
Local controller query if SWA was rolling would also seem to confirm tower had no visual on 18L surface movements. Looking at airport diagram, looks like tower is around 3,000 ft from the approach end of 18L. Given reported RVRs and darkness (30 min prior to sunrise), seems reasonable to conclude tower had no visual.