The first towers of the Hennessey supercell formed over us in Weatherford and moved off to our NE, while the other storm had already formed near the triple point W of Leedey. We discussed the pros/cons of each area for an hour while driving N and stopping near Oakwood. Finally, we decided to go after the more mature western storm, since the Hennessey storm might move over the cool outflow too soon. Our first approach to the western storm, now in the Canadian River valley, came a few miles outside Oakwood. The town name tells much about visibility there, and it took a few minutes to find an open area. This was after driving N on a section road toward hwy 51 and hitting low stratus and fog on the outflow boundary! That same slop surged SW along the forward flank of the supercell and killed any visibility we had W of Oakwood (somewhere in here we lost Jack Beven of NHC - he apparently began following the wrong pickup to Seiling!). So, with poor visibility and cool NE flow into the wrn storm along the outflow, plus lower dewpoints to its S in the warm sector (only low 60s), we bailed out and made a run at the Hennessey storm. This lasted about 20-30 mins as we got to a position halfway between Watonga and Kingfisher. The wrn storm seemingly had accelerated to the ESE and wasn't that far away, and it didn't seem like we'd catch the eastern storm until near I-35. So, we turned N and resumed our intercept of the wrn storm! Our thought was it would strengthen when ingesting the richer moisture about 1/2 county to its east, even though it was somewhat high based and outflow dominant in appearance at this point.