'Sometimes you go out there and hit your driver well and you hit your irons well but the putts won't fall,' said Carter. 'Other times you may not hit your irons well. I feel like I've been playing well for a while but I haven't been shooting good scores. Today, everything was good.'
Gavin Coles carded a 4-under 66 to finish second before a weather delay that pushed the start of the opening round back three hours ultimately cut the first day short due to darkness at Hardscrabble Country Club.
Play is set to resume Friday at 8:45 a.m. ET.
Carter played the back side first and began his run with three consecutive birdies starting at the par-5 11th.
The 42-year-old, who captured the PGA Tour's Tucson Open in 2000, stumbled to a bogey at the par-4 14th. He recovered well, however, with three straight birdies from the 15th to make the turn at 5 under.
Carter continued his fine play on the front side with back-to-back birdies starting at the par-4 first.
He then closed with a birdie at the ninth, his last, to give himself a great standing early in the tournament.
'I made the kind of putts you're supposed to make,' said Carter. 'It's nice to get off to a good start and make some birdies. It's like you've got some house money and that frees you up a little bit.'
Coles, who earned his second career victory on the Nationwide Tour at the New Zealand PGA Championship earlier this season, tallied five birdies and a bogey to finish four shots off the pace.
'I had only one bad iron shot all day and it cost me a bogey at 18,' said Coles. 'I played well here two years ago and I like this golf course.'
Jeff Freeman stood at 4 under par through 16 holes when play was suspended for the day. Justin Bolli was also at minus-4 through 15 while Vance Veazey completed 14 holes at 4 under.
Fran Quinn carded a 3-under 67 before the round was called to finish five shots back.
Also among those who were able to get their rounds in on Thursday was Ty Tryon, who was one shot further back after a round of 68.