Twenty-nine percent U.S. employers intend to hire workers for the summer, an increase from 21 percent in 2011 and an average of 22 percent over the past four years, with much of the hiring coming from the manufacturing, hospitality and retail sectors, according to CareerBuilder's annual Summer Job Forecast, conducted by Harris Interactive.

Among these top industries, employers expect to hire summer workers in manufacturing at 45 percent, hospitality at 44 percent and retail at 34 percent. Following these industries is finance at 31 percent.

"Confidence is up among the employers we most closely associate with summer hiring. This is good news for job seekers, as seasonal work can often lead to full-time opportunities," says Brent Rasmussen, president of CareerBuilder North America. "A majority of employers told us they consider a summer position an extended job interview. The forecast is also a strong indicator that the job market will continue to strengthen as we come closer to the second half of 2012."