This might be the worst time to go to the desert. Also, the spring and fall temperatures usually drop to a level to make hiking much more enjoyable than summer months. Hiking in the desert is, simply put, more exercise. It's also more limited by the hiker's physical strength and stamina than hiking in moist climates. You really can't go lightweight because you need to carry your water.
Experts recommend taking one gallon of water per person per day.
For many people, this essentially limits the length of your trip to two or three nights. If you're planning a longer trip and the weight of your pack is stretching your physical abilities, cut out weight in other ways instead of reducing water supply. Shop for a super-lightweight tent and sleeping bag. Go with the lighter but perhaps less comfortable sleeping pad. It might be tempting to leave your tent home to save weight, but a tent can be a life-saver if bad weather blows in.