We have a tarp that packs up to something hardly bigger than your fist and covers the tent entirely. Most importantly, it is about 1.5 meters longer than the tent. So we use it when we know there will be evening rain but we want to sit outside the tent. We have gizmos that turn a sleeping pad into a chair and happily sit out, cook, drink beer and enjoy the sound of the rain all whilst being outside. So the tarp now and then makes for a great evening. When we tour in winter we usually don't take it because as soon as the sun goes down we need to be inside the tent for warmth. That can mean 12 hours in the tent. So, yes, a tarp can be fantastic in bad weather.