We were on this trip at the same time as you last year and were in the same dilemna as you. Egypt was at the end of a four month trip and we did not fancy carrying 2 sleeping bags for that long. Anyway, we brought one sleeping bag, rated at -5 C., and two sleep sheets and did just fine on the felucca. We used the sleeping bag as a blanket. The nights do get cool, but wear warm clothes and with a sleep sheet and a bag as a blanket, you should find it okay.