here are the reasons. Tightness in Alberta and BC, other than refinery outages, due to lack of railcars to move refined products. All the cars are in Crude service, poetic justice for BC, but unfortunately other provinces affected as well. Note: you will probably have to copy this link to your address bar to get the story.

http://www.platts.com/RSSFeedDetailedNews/RSSFeed/Oil/26967735