Here are some general ideas about the weather in Morocco,
Initially Morocco is in the northern hemisphere and thereby rain should fall between December and march, however, the country has undergone drought for more than five years, as a result, rain has fallen less than usual; so, any firmer predictions would be useless and confusing to the traveller. Nevertheless, there still general cases as will be mentioned below.
The Atlantic coast as far south as agadir receives over 200 mm/8 in of rain in winter, but father south the climate becomes gradually drier.
The northern coast of Morocco and the interior mountains have a Mediterranean climate. North-western Morocco, especially the Rif Mountains, is exposed to Atlantic depressions in winter and rainfall is moderately heavy.
Sea and air temperatures on the Atlantic coast are kept lower than along the Mediterranean coast by the cool waters of the Canaries current. Along this coast summer temperatures are significantly cooler than inland and the cold offshore water causes some cloud and fog in summer. Winters on the Atlantic coast are very mild and snow is unknown.
Inland in the high Atlas Mountains; the weather and climate are much influenced by height. The Atlas Mountains here are at their grandest with the highest point rising to 4,163 m/13,655 ft. winter snowfall can be heavy and the highest areas are snow-covered well into the summer.
Inland at lower levels the summers are very hot, while in winter and spring winds blowing off the mountains can cause some very chilly days. At medium altitudes the climate of Morocco is healthy and very pleasant around the year.
Summers are hot but the humidity is quite low while the winters are generally mild and sunny despite some spells of changeable weather The climate of the Saharan region of Morocco strong winds occasionally raise dust and sand which can be dangerous as well as most unpleasant. During the hottest weather there is some danger of heat exhaustion, or even heatstroke, except that in the south, where the desert reaches the coast, summer temperatures are moderated by the cool ocean waters and persistent daytime sea breezes. Here winter temperatures are also milder than inland.
Reference :
BBC - Homepage