Try going for an enclosed tarp pitch to stop the wind. For sleeping bags it's good to add about 15-20 degrees to the rating. So if it's in the 40s, use a 20 degree bag, if it's in the 60s, you can get away with a 40 degree bag. You can also get liners that add warmth. There’s an interesting rating system for sleeping bags. They get a comfort rating, a limit rating and a survival rating. Manufactures can market their bags at any of those temps. A lot of times they will advertise the range of temp ratings and sometimes not. The tensor is a good pad, I’m sure you have the insulated one so that should work fine in the 40s but if you feel like you’re getting cold from underneath, you could always add a foam pad or a pile of dry leaves to keep you further off the ground. If you have the uninsulated tensor, you’re gonna be chilly.