OPEC will meet on Thursday to discuss whether or not they will increase oil production. If they decide to raise it much higher than expected, the price of oil may decrease, as investors will most likely close their long positions. Also, the fact that oil is currently trading at 2018 high suggests that prices will correct soon, so investors will undoubtedly change into short positions.
With regards to dollar, demand is continuously growing, thanks to the recent announcements of the Federal Reserve.
Thus, dollar is rising in the medium-term, and there is a possible correction in oil before and after the OPEC meeting.
Considering this, it is a good idea to open long positions in the significantly oversold USD/CAD in order to set off a price increase.
Good luck and have a nice trading day!