By Larry Fine
LANCASTER, Pennsylvania, July 10 (Reuters) - Sunshine replaced overcast skies and thunderstorms at the U.S. Women's Open on Friday but scores took a turn for the worse at the rain-softened Lancaster Country Club.
Australian Hall of Famer Karrie Webb, unheralded American Marina Alex and 2004 U.S. Amateur winner Jane Park had shared the first-round lead with four-under 66s after the weather-interrupted opening round was completed on Friday morning.
Midway through the second round, afternoon starters Webb and Alex had dipped to three under, while Park was in the clubhouse at two-under 138 after a pair of late bogeys gave her a second-round 72.
South Korean Amy Yang edged ahead with a birdie at the fourth hole to put her name atop the leaderboard at four-under after completing five holes of her second round on the hilly, parkland course in the midst of Pennsylvania's Amish country.
Livelier winds, trickier pins and deceptively soft, slower greens seemed to confuse the early wave of players, including world number one Park In-bee, who posted an even-par 70 for 138 in her quest for a second major in a row.
"It was playing a little bit longer this morning and we got the wind as well," said Park, who won last month's Women's PGA Championship at Westchester Country Club. "The pin positions were a little trickier."
Park said it was hard to get used to the speed of the greens since U.S. Open putting surfaces usually run very fast.
"I hit probably every putt short," she said. "I think that's what everybody has been doing. It's hard to think that you have to smash the putts at a U.S. Open.
"I just felt like I was stupid because every hole I stood over and I hit it harder and I kept coming short."
Morgan Pressel, who shot an opening 68, joined Webb and Alex at three under with a birdie at the fourth.
Rumi Yoshiba of Japan posted a second-round 68 to join the group at 138.
Fifty-five players returned early on Friday morning to complete the first round after a dangerous thunderstorm blew through late on Thursday.
Jane Park birdied the 14th, her first hole in Friday's resumption of play, to reach four under.
The short-hitting Park, who ranks last in the tournament in driving distance, ran off 12 pars in a row in the second round as she stayed in the lead before a three-putt bogey at the par-five seventh and a bogey at her closing hole, the ninth.
"I give up a lot of distance off the tee, but my irons and my woods are very, very accurate," she said. (Editing by Mark Lamport-Stokes)