Canadian Lorie Kane and Candie Kung of Taiwan lead the field by two shots going into the final round of the Safeway Classic in Portland, Oregon.
Kung had a 68 and Kane shot 69 to end their second round at seven under.
Sweden's Carin Koch hit a 67 - the best round of the day - to lie joint third with compatriot Annika Sorenstam and Britain's Janice Moodie.
The only other Briton in the top 10 was Karen Stupples, who is on three under after a 73.
Moodie birdied three out of her of final five holes to lie nicely in contention.
The 31-year-old Scot had been 10th overnight and looked to be dropping
out of the hunt when the wind, rain and cold took its toll and she struggled to
the turn in 39.
But she hit back with birdies from close range at the fifth and sixth and then
she holed a monster putt at the eighth.
"The weather made it really tough out there, but I was delighted the way I
turned it round," she said.
"The last birdie was a 65-foot putt and these are the breaks that can make
your day."
But Sorenstam will potentially pose the biggest threat.