The Soulwind is a current that runs from Eludan to Yfasma.
It carries souls to the weaver's yard, so they can be remade there. The Soulwind can only carry anything that has been burned, as such mortals need to be cremated before their souls can be carried off. Often one's ashes will be spread into the winds from a high location, though that is not strictly necessary.

The Soulwind was created only after the Trinary system of Eludan was already in existence. Only once Tenebris became full did the need for a separate place for souls arise.

After the The Fall of Magic the Soulwind was adjusted at the request of Ysra. She could hear the pleading of mortals, who no longer had a way to contact the gods. Now it could not only carry the Souls of the dead, but also anything physical that was burned in the fire if it was cast into it with that intention. Mortals use this to make offerings to the Deities and to send their prayers in the form of written text.