Gulbis, seeking her first LPGA Tour victory, birdied the par-5 17th to tie Reilley Rankin and Mi Hyun Kim at 12 under. Kim also birdied the 17th just before play was stopped, while Rankin completed 16 holes.
Paula Creamer and Se Ri Pak were a shot back, and Annika Sorenstam also made a birdie putt on her last hole -- the 15th -- to pull within four shots of the leaders. Pak is trying to match Mickey Wright's LPGA Tour record of five victories in one event.
Play was stopped at 8 p.m. to afford course workers some daylight. Play will resume early Sunday morning, with the final round to follow.
Gulbis, the tour's cover girl, is trying to shed the image that she's all looks but doesn't have the game to play with the sport's elite. She's playing in her 126th tour event and despite cashing checks and threatening to win, she's never followed through.
She led at 9 under after rounds of 67 and 66, then dropped off the pace with a three-putt bogey from short range at the ninth hole. She recovered with birdies at the 10th, 15th and 17th holes to get a piece of the lead.
Rankin has not finished better than fourth in her 63 previous LPGA Tour events. She followed an opening 66 with a 68 that left her a shot behind Gulbis at the tournament's midpoint. She played steady throughout the third round, with five birdies and one bogey before play was called.
Kim completed her second-round 66 on Friday, then took a while to get warmed up in the third round. She had birdies at holes 9, 11, 12, 13, 16 and 17 before play was halted.
Creamer, after two rounds of 67, was 3 under through 17 holes while chasing her first victory in more than a year. She led after birdies at 7, 8 and 11, but dropped back with a bogey at the 15th.
Pak set the course record with a second-round 61 in winning the 1998 Farr at a record 23 under. She went on to repeat and then won in 2001 and 2003.
After two rounds of 68, she played bogey-free through 15 holes, with five birdies.
Sorenstam had rounds of 69 and 68 and was 3 under through 15 holes when the horn sounded.
A series of thunderstorms pounded Highland Meadows Golf Club with 2 inches of rain late Friday afternoon, suspending second-round play with almost half the field on the course. They returned to complete their second rounds late Saturday morning, with the third round starting midway through the afternoon.
A sign just across from the entrance to the course read: 'Parking $4. Free Water Rides.'
Ten Mile Creek, which meanders through the course, flooded its banks on Friday. What was a 75-foot wide trickle became a fast-moving, treacherous 75-yard expanse of water.
Players hopped in golf carts earlier in the day in order to traverse the deepening waters that bisected the first hole. They had to put their feet up on the front of the cart while water washed over the floor.
'You hope you make it through,' said Sorenstam, who won the Farr in 2000. 'It's kind of like you're at Disney World on one of the flume rides. I'm amazed that we're playing.'
As the creek continued to rise, tournament officials put together a makeshift pedestrian bridge that connected with the existing bridge over the creek. By late Saturday afternoon, the floodwaters were lapping at the bottom of the bridge.
Brown water lapped a few feet from the fringe of the par-3 second hole and transformed the front bunker into a mini-lake.
After the second round was completed, the third tee had to be moved to higher ground -- shortening the par-4 hole to around 280 yards. Laura Davies had little difficulty reaching the green with her drive.