Sunday's game at the Stadio Atleti Azzurri d'Italia was hours away from being called off as a heavy band of snow refused to leave Bergamo, but on-loan Inter Milan striker Marko Livaja ensured there would be a contest with his rapid opening goal for Atalanta.
Marquinho pegged Atalanta back before Miralem Pjanic turned the game on its head with an exquisite free-kick, only for Livaja to complete his brace heading into half-time.
Vasilis Torosidis waited for the snow to clear to head the winner and Atalanta promptly unravelled as Matteo Contini saw red following an unseemly scrap with Simone Perrotta.
The snow was still relatively light as Livaja opened his goalscoring account on his full home debut, the Croatian finding the net within eight minutes following a one-two with Giacomo Bonaventura.
Roma's response was swift, though, and four minutes later Marquinho dragged the southerners back into the match with a fine curling strike from the edge of the area.
A quickfire double was postponed when Pjanic's long-range free-kick skimmed the crossbar by a hair's breadth as the heavy snowfall began to affect proceedings in the Alpine city.
Michael Bradley could barely see as he cleared Bonaventura's speculative shot and Pjanic hit the ball and hoped for the best from a Torosidis corner.
The Bosnian did defy the conditions in the 34th minute, however, to rifle home a free-kick given when Guglielmo Stendardo fouled Pablo Osvaldo on the edge of the area.
Home keeper Andrea Consigli had been squinting to identify the ball on a pitch covered completely in white and he had Osvaldo's faulty radar to thank when the Italy striker scooped Federico Balzaretti's pass out for a goal-kick.
A dismal error from Contini allowed Osvaldo in again but he was not expecting the ball and so spurned the chance to make it 3-1.
He would certainly rue that missed opportunity when Livaja brushed off the attentions of Torosidis to drive home an equaliser off the inside of a post just before the break.
There was a seven-minute delay to the start of the second half as snow was hurriedly cleared from the pitch.
Indeed the conditions improved as play resumed and Nicolas Burdisso had no problem checking Livaja's run as he came looking for a hat-trick.
Contini blocked an Erik Lamela drive and Maarten Stekelenburg repelled Carlos Carmona's effort as the game opened up with the snow abating.
Consigli thought he had kept the scores level when he kept Pjanic's bullet header out from two yards but Roma would edge ahead once again in the 71st minute.
Torosidis was not as well placed as his team-mate had been when the ball sailed across the Atalanta box but the Greek rose well to nod it beyond a flailing Consigli.
There was plenty of time and desire left for Atalanta to force a draw and Stekelenburg was the hero when he pulled off a fine save from substitute Stefano Lucchini's header.
However, Contini both wasted his own side's time and did their chances of an equaliser no favours when he picked up a second yellow card and his marching orders for raising his hand to Perrotta.
There was no way back for the Nerazzurri and Consigli kept the scoreline respectable with one last save from Lamela as time ticked away.