There is no problem with a Glock in cold weather. Lots of Alaskan cops use Glocks. I'd just take the advice already given and keep the striker channel clean and dry, using NO lube there. I'd also recommend Mobil 1 100% synthetic oil for lubing with four-five small drops at the recommended spots.
Any further concerns about using Glocks in cold weather might better be addressed by a little psychotherapy and meds for OCD!