Placement and Biomes

[Hikki-Jin]

All right, hopefully this is the right section. This is one of my first maps (not counting rough doodles from years ago). It's the northern half of a continent, in the northern hemisphere. For simplicity the planet's size, gravity, orbit, physics, etc is all comparable to Earth. The dark brown lines and squiggles are roughly where mountains are planned to be.

Anyway, I have two questions:

1) Is the placement of the mountains, rivers, and lakes geographically accurate thus far? Is there anything else that looks out of place in that regard?
2) If the answer to the first question is "yes" (or won't require any significant changes) then advice on the biomes would be greatly appreciated. The southwestern area, ringed by mountains as it is, I imagine to be primarily a hot desert. I see the northern islands and mountains as being cold.