Howden was the 19th qualifier but battled his way through the heats - including making an impressive start in the big final that saw him get out in front early - to take top spot and slash the lead in the overall standings of Jared Schmidt, who was unable to progress past the first race on Saturday.
Terence Tchiknavorian of France finished second in the big final, while Switzerland's Alex Fiva, who made it into a big final for the first time this season, finished in third.
"Every heat it seemed to kind of improve for me," Howden said. "I really would like to thank all the volunteers who did an amazing job working really hard.
"I'm super happy with the way the team skied today. Jared's been pushing hard; he didn't have the best of luck today but everybody's firing and I'm just really happy.
“To be able to perform in front of friends and family is unreal. I had a lot of fun today.
"My dad's right over there, the family's here and every heat I just got more confident and more confident - that's a big part of it.
"That last heat I just was feeling really confident in the start gate. With the start it's really key for this course. I just focused on that and I figured the rest would just fall into place. I'm super stoked, super happy to be back on the box. Hallelujah!"
Tchiknavorian, who won the last men’s race of 2023 in Innichen, started the day in second place in the overall standings - 135 points adrift of Schmidt. That lead is now down to 70 points after his second-place finish in Nakiska, and Howden is a solitary point behind Tchiknavorian in third.
“It’s a good way to start the new year. I started almost like I finished it, so I’m pretty happy about this second place today,” Tchiknavorian said.
“I was happy about my skiing I did today, I did good stuff again and I was happy to be on the podium with Fiva and Howden. (Howden) was too fast for me so I’m pretty happy with this second place.”
Looking ahead to day two’s racing, Tchiknavorian said: “It’s not easy to make some passes, so the best way to make a good race is start first; at the first turn to be first or second. The course is pretty fun but pretty tight.”
Fiva said: “My starts were terrible and got worse and worse. I just kept calm and tried my best skiing.
“You have to be calm because it’s a really difficult course; a lot of jumps and a lot of tight turns. At the end on the podium is always great.”
Schmidt spurred on by home support and Lady Gaga
Meanwhile, in the women's section Hannah Schmidt and Marielle Thompson made it a Canada one-two with dominant skiing in the big final, with Switzerland's Fanny Smith finishing third and France's Marielle Berger Sabbatel, who is yet to miss a big final this season, narrowly missing out on a podium place.
Coming into Nakiska as the overall leader, Sweden's Sandra Naeslund had made it to the semi-final stage of the event, but then pulled out of her race before the start. It means Berger Sabbatel has now moved into the overall lead on 400 points, with Naeslund in second on 387. Schmidt is 18 points behind Naeslund in third, and Thompson is fourth on 322 points.
"I woke up this morning feeling pretty good," Hannah Schmidt said. "I've been skiing fast on the track all week, and just to kind of put it all together on race day feels pretty good.
“It’s amazing. Having everyone cheer when you cross the finish line, it’s honestly breathtaking and it feels so good.”
Asked to put a theme song to her victory, Schmidt said: "Every time in the start I sing in my head 'LoveGame' by Lady Gaga - "let's have some fun" - that is literally my theme song!"
Thompson said: “Today was good. I was so close, had I not been a little short on the last jump I might have had Hannah.
“It’s definitely very special to be on the podium at home. I had lots of people here, friends and family, cheering me on. We could almost hear them from the top which is very cool. Hopefully another one tomorrow, maybe one step – I’ll give it my all.”
Switzerland's Talina Gantenbein won the small final to finish fifth overall, followed by Canadian pair India Sherret and Brittany Phelan. Naeslund was awarded eighth after making it to the semi-final stage but not racing.