Graeme McDowell carded a 64 for a three-way share of the lead at the Scottish Open, but round two was unable to finish due to the threat of thunder.
McDowell, who won the event in 2008 at Loch Lomond, had a bogey-free round at Castle Stuart, with an eagle at 12.
McDowell was joined on 11-under-par at the halfway stage by Scottish pair Scott Jamieson and Peter Whiteford.
World number one and two Luke Donald and Lee Westwood are among 78 players still to complete their second rounds.
The first delay came at 1500 BST and lasted for a fraction over two hours, but when the storm passed through it was felt the second round could still be completed, given the amount of summer evening light in Scotland.
However, shortly after 1800 BST the weather closed in again and there were further concerns about electrical storms.
Donald collected three birdies and was seven under halfway through his round.
Westwood, the joint first round leader, remained at seven under after 11 holes, the highlight of his round coming at the 10th when a pitch screwed back agonisingly close to the flag and finished a matter of inches away.
Former European Ryder Cup captain Colin Montgomerie, who needs a top-five finish to retain a chance of qualifying for next week's Open, had successive birdies to briefly reach seven under.
But the 48-year-old dropped a shot at the seventh for a share of 25th place and was anxiously surveying the result of his approach to the 10th in thick rough below the level of the green when play was abandoned.
European Tour rookie Jamieson has recorded four top six finishes already this year, including a share of third at the BMW International in Munich after graduating from the Challenge Tour.
The 27-year-old from Glasgow began his second round from the 10th hole and took a bogey five there but then posted five birdies in succession.
Eagles at the 18th and the second took him to 13 under and at that stage he was four shots clear of the field.
However, he came up short of the green on the 218-yard eighth, left his chip on the fringe and three-putted.
"That was disappointing, but it's exciting to be in this position in Scotland and to get my first win here would be fantastic," he said.
McDowell was lying in joint 30th following his opening 69, but the 2010 US Open champion was delighted with his second round.
"I hit the ball really well and the golf course played beautifully," he said. "It was a beautiful morning and you couldn't ask for more perfect scoring conditions."
Four-time major winner Phil Mickelson recovered from an opening 73 to post four birdies and an eagle in a 67 which lifted him into a share of 50th place at four under, and the popular left-hander is expected to survive the halfway cut.