Is Morocco humid or dry?

The honest answer is "both, and where you stand decides it." Most of Morocco, the interior plains, the mountains, and the entire desert south, is dry, sometimes extremely dry. That dryness is a gift in the heat. In the Sahara I have stood in 42°C that felt far more tolerable than a humid 32°C back home, because your sweat actually evaporates and cools you. Dry heat lets you function; you just drink constantly because you are losing water without realising it.

The coasts are a different story. Casablanca, Rabat, El Jadida and the whole Atlantic strip carry real ocean humidity, and in high summer it gets muggy and close, with hazy grey mornings the locals call the "marine layer." Essaouira is windy enough that it rarely feels oppressive, but cities like Casablanca in July and August have that sticky warmth where the temperature reading does not tell the whole story. The Mediterranean north around Tangier and Tetouan is humid too, lush and green precisely because of that moisture.

Inland imperial cities sit in between but lean dry. Marrakech and Fes in summer are hot and arid rather than humid; the air is thin and dusty, lips and skin dry out fast, and a scarf and lip balm become daily kit. I always tell people the practical consequence of dry air is dehydration sneaking up on you, so I push water hard on desert and city days even when nobody feels especially sweaty.

If humidity bothers you personally, the planning rule is simple: head inland and up for dry comfort, expect stickiness if you base yourself on the coast in summer, and remember that the desert's famous heat is the dry kind that most people handle better than they fear. Pack moisturiser and lip balm for the dry interior, and lighter breathable layers for the humid coast.