Worst seasons: Christmas in Egypt and Easter school holidays are hugely overpriced and overcrowded while June-September is massively hot, especially around Luxor and Aswan; expect 35C-45C+/ 95F-113F+.
In wintertime, December-February, nights will be chilly in Cairo but with T-shirt days. The further north the colder, so Alexandria might be unpleasantly chilly, according to personal acclimatisation.
Length of stay?
Minimum worthwhile stay, not including flights: 4 days (Cairo only) Recommended: 2 weeks – 4 weeks for an all-Egypt encounter.