If your Weimarana is anything like my Viz you will struggle to keep him warm. I have a stoney creek jacket for normal three season hunts plus a swazi for when it's wet or windy. If it's at all cold he sleeps under my puffer jacket or he is restless all night.
Sitting around glassing in the cold is still an issue even with two jackets on so looking at getting him a dog puffer jacket.
Bookmarks