The return of the ‘summer sweater’ — what is it, and where to shop on sale

New York Post Composite We’re in that awkward middle phase between summer and fall, where sometimes finding the right outfit to match the fluctuating weather can be a major headache. Short-sleeve season is far from over, but you might find yourself pulling out a jacket at night for the first time in several months. Transitional pieces can be tricky, but we’re taking the guess work out of your summer-to-fall closet switch. Enter the summer sweater. According to celebrity stylist Sammy J Watts, the design is an “unexpected hero of warm weather dressing” that’s lightweight enough to throw over your shoulders under the sun, then slip on later into the evening with jeans. She noted how the silhouette often harkens back to Carolyn Bessette Kennedy’s effortless, minamlist style of the 1990s. “We’