I've lived in B.C. a long time now, my whole life... and to be honest I don't think i've ever experienced a "Chinook." Tho I have expereinced freezing gusts of wind that come from no where.
Thanks to the warm air that comes up the coast, the weather here is pretty nice all year round. Good enough to wear shorts all year round, well, for me atleast. Only bad thing is that i'm so use to the colder temperatures that even 25 Celcius (~77 Farenheit) is uncomfortably warm for me.