The return of snow also means the return of videos of dogs playing in snow.
Aigner comes to the Rapids after spending this past season with 1860 Munich of the second-tier Bundesliga 2.
Orlando City SC's Joe Bendik only had to make one save to earn his third shutout.
Dominique Badji scored, Zac McMath made three saves and the Colorado Rapids beat the New England Revolution.
Howard pulled a muscle in his right leg during Friday night's 2-1 loss to Mexico in a World Cup qualifier and was replaced by Brad Guzan late in the first half.
The second-seeded Rapids got a first-round bye after narrowly missing out on the Supporters' Shield to FC Dallas.