The Americans also defeated Scotland 4-1 on Saturday.
Megan Rapinoe opened the scoring in 21st minute, controlling a difficult ball in the penalty area and striking magnificently with her right foot to put the U.S. ahead with her 20th goal.
Wambach, in her 200th game for the Americans, doubled the advantage six minutes after the interval. Heather O'Reilly pushed a pass ahead into the Scottish box for Sydney Leroux. The 22-year-old struck a low cross into the middle that Wambach finished with a diving header from close range.
Christen Press, who scored twice in her international debut on Saturday, closed the U.S. goal account in the 54th minute, netting from 10-yards out.
Scotland cut into the deficit nine minutes from time as forward Suzanne Grant, playing in her 100th match for her country, volleyed home a cross from the left side.
Next up for the U.S. is the Algarve Cup in Portugal that will take place March 6-13.