Imaging of faint optical emissions from the upper atmosphere allows direct detection and monitoring of many space weather phenomena impacting on terrestrial and satellite communications and navigation systems. A low cost means of monitoring space weather over large areas from the ground has been a long-sought after but elusive goal. Algorithms are described for acquiring ground based night sky images and extracting the motion of clouds and upper atmospheric structures from such data. Both spatial decorrelation and optical flow techniques were explored for single and multiple nighttime sky imagers.