The uncapped 28-year-old finds himself in the squad along with Jordan Pickford, Jack Butland and Marcus Bettinelli, and he has promised to make the most of the opportunity to impress the manager.
“I want to give him a decision to make,” he said. “Obviously I've been called up for a reason and there's now four of us here, but it's a time for me to go out there and prove what I can do.
“We're away for seven or eight days, so it's enough time to sort of show him what I can do.
“I've been in two squads before but that was quite a while ago, so obviously after the World Cup and everything that has gone on it's been a positive for English football.
“It's nice to be back involved and a part of it.”
McCarthy won his place in the Southampton side last December from Fraser Forster and went on to be named his club’s Player of the Year by his fellow professionals.
After narrowly beating relegation last term, Saints have made a decent start to the Premier League season, earning four points from four games, and now McCarthy is eager to end a fine spell with a cap.
“We have had a positive start to the season and to get the call-up was the cherry on the top,” he said.
“When you are growing up as a kid, all you want to do is play football and represent your country.
“If I do get my chance, I know I will take it. I will be overwhelmed.”
He started his career at Reading, where he played 70 times in the league but spent eight periods away from the club on loan, including to non-league sides like Team Bath, then failed to make the grade at either QPR or Crystal Palace before breaking through at St Mary’s.