Stenson's round began early when conditions were described as "serene" and turned in a 7-under-par 65 for a 36-hole total of 13-under 131.
Storms moved in during the afternoon and play was suspended with most of the field still on the course. Among those who will have to finish his second round Saturday is first-round leader Merrick Bremner, who was 1-under on the day through 14 holes.
That left Bremner tied with Magnus A. Carlsson at 9-under for the tournament. Carlsson shot 5-under 67 in his second round.
Lloyd Saltman, with a 66 Friday, is alone in fourth at 8-under with a trio of players tied at 7-under.
Bremner's round Friday included a double bogey at the par-4 13th and a bogey at No. 5 -- his 14th of the round -- as play was halted. Carlsson had a bogey and six birdies, three of which came in his final five holes.
Stenson started his second round with five pars before posting five birdies in a seven-hole stretch that gave him the lead. He pushed his advantage with an eagle at the 576-yard, par 5 eighth hole.
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