UPDATE 6:18, tornado (circled) outside the warning polygon. Moving N to NNE near US 177 (highlighted). The storm is -- temporarily -- weakening.
At 6:09pm, tornado moving east. I've circled the tornado and the City of Stillwater,
From Jeff Piotrowski, here is an image of the tornado at 6:14pm, near Perkins:
here is an image of the tornado on the ground at 6:13pm.