I think you'll struggle to find anything really good with-in an hour of Osoyoos. I'm in Kelowna, an hour & half away from Osoyoos and am 30 minutes from Greystokes and 1.5 hours from Hunters Range or closer to 2 hours from Siccamous. I haven't heard of any great riding in the South Okanagan.
Osoyoos is in the desert There snow accumulations are minimal and the closest would be to the West and the Cascades....but they aren't anything like the north end of the Valley. I have a buddy who lives in Osoyoos.......he rides in Revy....4 hours away.
PG is similar.....flat flat flat. Travel to Barkerville or Kakwa......but each is more than an hour....more like 2. Plus its a bit cooler......but the snow can be awesome after a pretty big cycle.
Best riding in the Province is the Monashees, Selkirks, and Coast Mountains. Always consistent snowfall, but more tourists .
Hope that helps.
RS
2 hours north of PG, you will find some of the best powder in the province. It is generally a bit colder than the rest of BC, so the snow stays light, dry, and fluffy. 2 hours southeast of PG, and you will be into Valemount or McBride. Great riding areas, but lots more people.
I've heard good things about the back country around Sun Peaks, though I have never been there. Siccamous is only an hour & a half away from Kamloops and is awesome.