Ahot, steady south wind that blows from north africa across the mediterranean sea into southern europe is called the

Sirocco wind

Explanation:

The Sirocco wind usually refers to the warm, moisture containing wind that originates from the northern part of the Mediterranean Sea as well as the southern part of Europe. This wind moves from the southern/southeastern direction and carries the unbearable moisture containing air.

This hot and steady south wind arises over the region of North Africa in the form of dry wind and eventually carries the moisture content in it as it travels across the Mediterranean sea, and thereby reaches the Southern part of Europe.