Tournament officials suspended the action at 2:45 p.m. ET because of heavy lightning, which struck five times within a mile and half of the course. Play was finally called for the day at 7:25 p.m. with half the field unable to start their rounds.
Two inches of rain also fell during the storm.
The players who were able to tee off will resume their rounds at 8:30 a.m. on Friday, while those who where slated to go off in the afternoon wave Thursday are now scheduled to begin Friday at 10:30 a.m. Friday's forecast calls for more scattered storms.
Hunter Haas recorded three birdies and an eagle through nine holes for the lead at five-under par. Michael Flynn made it to four-under with a quartet of birdies through six holes, while Eric Meeks (through 11 holes), Todd Fischer (nine holes) and Grover Justice (six holes) were together minus-three.
Defending champion Jay Delsing was among 19 golfers bunched up at two-under. No player has ever successfully defended his title in the 13-year history of the Buy.Com Tour.
Lightning storms plagued last year's Fort Smith Classic, with delays on three of the four days. Although all 72 holes of regulation were completed by Sunday, only one hole of the sudden-death playoff between Delsing and Jeff Freeman was played before darkness forced play to be suspended.
Delsing won with a par on the fourth extra hole Monday morning.
Full field scores from the Fort Smith Classic