Egypt’s climate is easy to summarise. Except for the winter months of December, January and February, it is hot and dry. Temperatures increase as you travel south from Alexandria – northernmost city. Alexandria receives the most rain – approximately 109mm a year – while in Aswan, in the far south, rain is rare.
Summer temperatures range from 31°C on the Mediterranean coast to a scorching 50°C in Aswan. At night in winter, the temperatures sometimes plummet to as low as 8°C, even in the south of the country. In the mountains of Sinai, night-time temperatures in winter can fall well below zero.
June to August is unbearable in southern Egypt, with daytime temperatures soaring up to 40°C or more. Summer in Cairo is almost as hot, and the combination of heat, dust, pollution, noise and crowds makes walking the city streets a real test of endurance.
For visiting Northern Egypt, winter is easily the most comfortable time. In Cairo from December to February, skies are often overcast and evenings can be colder than you’d think, while up on the Mediterranean coast, Alexandria is subject to frequent downpours.
Climate Chart for Cairo
Take a look at this http://www.timeanddate.com/weather/egypt/cairo/ext