David Toms and overnight co-leader Craig Parry are one back at minus 19, while Chris Smith and Jonathan Byrd are one stroke further back at 18-under. Stewart Cink is alone in seventh place at 16-under 200, four behind the leaders.
For the third straight day, the field at Callaway Gardens played under lift, clean and place rules due to heavy rain prior to the first round and continued soggy conditions since.
Huston, who missed short putts at 1 and 2, caught fire from there and climbed towards the top of the leaderboard. He birdied six consecutive holes beginning at the third and made the turn at 15-under.
Huston continued the hot play with birdies at the 10th and 12th. He then sank consecutive birdies beginning at the 14th, where he chipped in from 40 feet. He had a chance for eagle on the 15th, but missed a 12-footer before tapping in for birdie.
'If I made that, I thought I had a chance to shoot in the 50s,' Huston said, who also missed an eagle opportunity at the seventh.
The final birdie of his round came at the par-4 17th, where he made a three-footer. He had a chance at 18, but his 15-foot birdie putt lipped out.
'You just can't let up,' said Huston. 'I was trying to keep the pedal to the metal and keep going, knowing that everyone else was playing under easy conditions.'
Herron, who shared the overnight lead with Parry, got his round going with a birdie at the third. However, he gave that back with a bogey on the fifth. Herron regrouped and made consecutive birdie putts starting at the seventh.
The 1999 Bay Hill Invitational winner birdied three straight holes beginning at the 10th. He secured his spot, with Huston, atop the leaderboard with birdies at the 14th and 15th. Herron knows, however, that with the impending bad weather, he still has a tough go of it ahead.
'It was going through my head a little bit,' Herron said, referring to the forecast that calls for Sunday rain. 'It's not the end of the world. I'm still going to have to make a lot of birdies to win this tomorrow.'
With the seemingly easy conditions, due to the lift, clean and place rule, 12 players shot 65 or better, and the average score on a damp, overcast day was 68.2. That left Parry feeling bad about his round.
'I feel like I've just shot par,' Parry said after his 66. He had a chance to take or join the lead, but he parred 17 and 18.
Robert Allenby, Ben Crane and J.L. Lewis are five shots behind the leaders at minus 15. Joey Sindelar, Rocco Mediate, Kent Jones, Olin Browne, Billy Andrade, Kenny Perry and Phil Mickelson are one stroke further back at 14-under.
With the Tour Championship looming next week for the top 30 on the money list, players are jockeying to get into that elite field.
Brad Faxon, who currently occupies the 30th spot on the money list, climbed to 8-under-par with a 69 Saturday. He is tied in a large group at minus 8. Perry, who is in the group at 14-under and currently 31st on the money list, has a chance to pass Faxon on the money list and gain entry into the Tour Championship.
Poor weather conditions are expected to hamper play on Sunday. Tee times have been moved up several hours with the first groups teeing off, the first and 10th tees, at 7:10 AM ET.
Full-field scores from the Buick Challenge