He's come a long way from the fresh-faced 19-year-old who marked his test debut against England in Napier six years ago with five for 55, then a six-laced 77 not out when the test was in its death throes.
Southee took six for 51 at Sabina Park off 24.2 overs, 11 of them maidens to spearhead a smart bowling operation. He's been doing that for a while now.
Consider Southee was dropped for a time as his bowling lost its direction and consistency. At one point he missed four out of five tests in mid-2012.
But after snaring seven for 64 in an innings against India at Bangalore on his return to the side, Southee hasn't looked back.
He has got his bowling in a fine groove, swing and seam allied to a nagging line have brought significant rewards. Now he is the leader of the bowling group, and becoming a senior figure in the New Zealand group dynamic.
"We have a raw and young bowling attack and it's an exciting attack to be part of. We all bounce ideas off each other, throw things around.
"There's a lot of stuff that goes on behind the scenes. Bondy [bowling coach Shane Bond] and the bowlers set plans for each batsman and it's pleasing to see them come off and know we are doing the right thing behind closed doors."
Southee acknowledged perhaps the biggest change in his philosophy over the years he's been in the test side.
"The more cricket I've played the more patient I've become.
"When you're young, you want to take wickets every time you bowl. The reality is it's not going to happen.
"Test cricket is tough. You work spells to try and pick up wickets and you may not get it in the first spell but when you come back and keep applying pressure the rewards will come.
"One thing I've learned is if the wickets aren't coming, don't go looking for them. Especially on wickets like this [Caribbean]. Patience is going to be massive."
Southee demonstrated that at Sabina Park, nagging away in areas where perceived weaknesses had been spotted. Getting rid of the local hero, Chris Gayle, twice in the test, was a special treat. Southee knows those moments should be enjoyed; Gayle doesn't often fail against New Zealand. He has averaged 70.25 in 10 tests against New Zealand. Dismissing him for 10 at the start of the West Indies second innings started their slide to a 186-run defeat.
"To bowl on an unresponsive surface and create the uncertainty he did throughout the test shows what a quality bowler he is," New Zealand coach Mike Hesson said.
"He got the new ball to swing, got the old ball to reverse, and he always looked threatening."
New Zealand flew to Trinidad early today for the second test, starting early on Tuesday (NZT).
Among the varied reports New Zealand had received about the likely state of the Queens Park pitch in Port-of-Spain was that more grass had been left on it than usual.
New Zealand are reserving judgment until they see how it shapes up before the start. But if those reports are correct, Southee and his Northern Districts new-ball mate Trent Boult will welcome the change from the unhelpful Sabina Park strip.
Southee compensated for those difficulties admirably. A chance in more seam-friendly conditions would be relished. But Sabina Park reinforced the thought that Southee, at 25, is making himself a force no matter the conditions.
This week's performance has jumped him three places to No 5 on the world rankings.
