From the sample and the community replies, this does not look like simple focus error alone. Two likely causes were identified:

1. Camera shake / slow shutter speed — The blur appears fairly uniform, while point light sources show smear consistent with movement during the exposure. In cold outdoor light, your camera may be choosing a shutter speed that is too slow to hand-hold. A common guideline is to avoid shutter speeds slower than about 1 / focal length on 35mm film.

2. Rangefinder focusing mismatch in extreme cold — If your camera uses a rangefinder-style focusing system rather than viewing focus through the taking lens, very low temperatures could potentially throw the focusing mechanism out of alignment slightly.

So yes, the cold may contribute, but the most obvious issue from the photo is motion blur. Try using faster film, shooting in brighter light, bracing the camera better, or using a tripod. If the problem happens only in deep cold and only with rangefinder focusing, the camera may also need checking for cold-weather alignment.