Two strokes behind leaders Cristie Kerr and Lizette Salas entering the round, Nordqvist closed with her second straight 5-under 67 for a one-stroke victory over Salas.
Projected to jump from 16th to ninth in the world, Nordqvist finished at 13-under 275 and earned $255,000.
Salas birdied the 18th for a 70.
Nordqvist, who changed equipment and started working with instructor Jorje Parada during the offseason after considering leaving the tour, made a short birdie putt on the par-4 first hole and added birdies on the par-5 eighth and par-4 ninth to make the turn at 11 under. She also birdied the par-4 13th, par-3 14th and par-4 16th before dropping a stroke on the par-5 17th.
Lexi Thompson was third at 11 under after a 68, and Chella Choi was another stroke back after a 69. Kerr closed with a 73 to finish fifth at 9 under.
Park, preparing for her major title defense next week in the Kraft Nabisco Championship in Rancho Mirage, had a 68 to join third-ranked Stacy Lewis (71), Se Ri Pak (69) and Eun-Hee Ji (71) at 8 under. Michelle Wie had a 70 to finish in a share of 16th at 5 under.
Laura Diaz had a hole-in-one for the second straight day to become the second player in LPGA Tour history to make two aces in a tournament.
Diaz aced the par-3 third hole Saturday in the third round, then holed out on the par-3 sixth on Sunday — a shot she followed with an eagle on the par-4 seventh. She also had an eagle Saturday on the par-5 fifth.
Jenny Lidback is the only other player with two aces in an event, accomplishing the feat in the 1997 Tournament of Champions.
Diaz used a 6-iron Sunday on the 157-yard sixth. On the eagle on No. 7, she holed out from 122 yards with a 50-degree wedge, the club she used to hole out twice Saturday. She's the first tour player to follow an ace with an eagle on the next hole
The 38-year-old Diaz shot 2-under 70 in each round to finish at 2 under.