I am aware that a magnetic storm is a solar flare, which probably wouldn't affect the Earth's magnetic field. However, the game only states that a geomagnetic disaster has occurred. This could possibly refer to a magnetic pole reversal. Plus, it is evident ingame that this is not a simple, run-of-the-mill magnetic storm. There are several unforeseen, interesting effects of this disaster. Just look at the strange behaviour of the wildlife, and even the humans. For example, the idiots who were freezing to death, and decided to spend their last moments locking an empty safe! I mean, really? What kind of person would do that?
In the end, this is just a game, and it doesn't have to be completely realistic. I assure you, many people have suggested the inclusion of a compass before on these forums, and the answer has always been no. Regardless of the realistic reason why they 'wouldn't work', a compass would probably just be too overpowered - after all, you're SUPPOSED to get lost in blizzards (it's all part of the fun!). If you really need some navigation help in fog and snowstorms, try making your own simple markers, by dropping unneeded items such as tinder, and placing them (using Right-Click, on PC) to form lines and arrows.
About the crafted clothing, they only have a tiny chance to scare away predators, but the protection is still quite good. Personally, I do feel like they weigh a little too much, and I don't use them that often, but in my opinion, they're more of a end-game last resort for avoiding frostbite, rather than a viable clothing option.
Finally, yes, the calorie system does need some MAJOR balancing. Until then, exploits for the win!