[Rangefinder]

Should be fine so long as it doesn't get picked at too badly by scavengers overnight (coyotes, etc). So long as you have good landmarks picked out (where the deer was, where you were when the shot was fired, you should be fine to go back at first light and pick up a blood trail. Look for the roughed up dirt from the roll, and you should pick it up pretty quick. If it was hit good, it likely crawled down into a thicket to bed down and will have died pretty soon after. Just do your damnedest to try to find it and clean it quickly and your meat should be just fine in those temps.