I agree with the above, we have been to sharm in Apr/May, june (several times), July August and several times in November. To enjoy Cairo and Luxor to its full benefit is to go in the cooler months. I went to cairo in July and my flip flops melted, and the majority of people in my group going to Luxor stayed on the coach all day as it was cooler. You just cannot take anything in properly. January/February may have a few spots of rain, and March is nice as is April, but a light jacket maybe required at night. May is in the 80s and very warm. June to october has very hot and i mean hot temps ranging from in the 100s to the 90s in October. To much AC, booze and dehydration and eating beef will cause upsets tummies to some. I personally am a lover now of November, middle 80s in the day and fresh when you get up, not stifling like the summer months, night time lovely, may need a cardi. Only downfall for some would be you need to be up early to take full advantage of the sun. The sun goes down 4.30pm, so the days are shorter, but great sunsets to be had.
Michelle x