snow entering through attic roof vents

Answer 1

 In the blizzard on Feb. 1st and 2nd (2011) we discovered a lot of snow had blown in through all of our attic vents and fans. Help! While the wind was unusually high, we never want to experience this again...cleaning up several inches of snow from our attic in the middle of the night. Who do we call to fix this problem? A roofer? What kinds of vents and fans would be needed to prevent rain and snow in the future?