The delayed-but-fierce weekend snowstorm resembles the Avalanche’s offense this season. It has arrived, and as expected, it is formidable.

Teenager Nathan MacKinnon caused hats to drop like snowflakes Sunday at the Pepsi Center as his three goals powered Colorado to a 5-4 victory over the late-game rallying Tampa Bay Lightning. The Avs made their shots count, producing just 18 for the game and only getting one power play opportunity (0-for-1).

The visitors (32 shots, 0-of-3 power play) scored two late goals and had several good chances on a 6-on-5 attack in the final minute, but the Avs hung on for their fourth win in five games.

“It’s been an up-and-down season, lot of downs in terms of the team and winning, but lately we’ve been playing some solid hockey,” MacKinnon said. “It’s good to see the puck go in for my first hat trick, for sure.”

Suddenly, one of the NHL’s most disappointing offenses has produced 19 goals in its last five games, and that includes a 4-1 loss to the Los Angeles Kings in which Colorado had 43 shots against red-hot goalie Jonathan Quick.

“We knew the damn would break and it would be a big river throwing through,” Avs center Matt Duchene said of MacKinnon and the offense in general.

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At 19, MacKinnon is the youngest player in Avalanche history to produce a hat trick, and he did it in style-point fashion. He scored on the backhand inside the far post, on a redirect inside the near post, and with a wrist shot under the near-side glove. His shooting percentage was 1.000 (3-for-3).

“I don’t care about how they went in, just happy they did,” MacKinnon said with a grin. “I wouldn’t have cared if all three went off my butt.”

Duchene also scored with a fierce wrist shot, left wing Gabe Landeskog had an assist to extend his scoring streak to six games (five goals, two assists), Ryan O’Reilly had two helpers and Alex Tanguay struck for his 16th goal to make it a 5-2 game midway through the third period.

Tampa Bay’s Brett Connolly and Nikita Kucherov beat goalie Semyon Varlamov at 11:43 and 18:58 to give the crowd of 17,385 some anxious moments in the final minute.

“They’re a good team and they score a lot of goals,” Roy said of the playoff-bound Lightning, which is tied for second in the Eastern Conference with 80 points. “We knew they could come back at any time. Varly made some great saves early in the game and was very solid (in the final minute).”

Tampa Bay played Saturday night at Arizona and its charter arrived at around midnight, but the Lightning produced eight of the game’s first 11 shots before the Avs began to take over.

MacKinnon’s backhander tied it 1-1 late in the first period and he gave the Avs the lead 3:10 into the second with his redirect off O’Reilly’s wrist shot from the left circle. Duchene and Tampa’s Tyler Johnson traded goals before MacKinnon beat backup goalie Andrei Vasilevskiy under the glove for the fourth and final goal of the second period.

MacKinnon has 12 goals on the season — five in two games. He scored twice Oct. 30 at the New York Islanders but has otherwise seen a substantial decline in goal-scoring since his 24-goal, Calder Trophy-winning rookie season. MacKinnon’s 24 assists surpass what he had at this point a year ago.

“He played really well, but he was playing really well before,” Roy said of MacKinnon, a right winger on the Ryan O’Reilly-centered line with Landeskog. “That line, it seems to me, clicks really well lately and sometimes you feel it’s a matter of time before it happens.”

MacKinnon and Colorado’s other core young forwards — Duchene, Landeskog, O’Reilly — are each in the midst of their best scoring stretch of the season.

“We are moving our feet offensively, our D are very active, we really work well as a unit of five and we’re not afraid to put pucks on net,” Roy said. “We didn’t have as many shots on net but I thought we still made some great plays offensively.”

Mike Chambers: mchambers@denverpost.com or twitter.com/mikechambers