The shirts and other supplies are expected to arrive in Turkey’s port city of Iskenderun in two days.
The small city was one of those heavily damaged by the Feb. 6 earthquakes believed to have killed more than 41,000 people in the region — a death toll that rises daily as rescuers continue to search through building rubble.
Iskenderun was also further damaged by subsequent floods and fires.
From Iskenderun, the thermal shirts will be brought to a refugee camp in Kilis, which is close to the border with Syria, less than 40 miles from Aleppo.
Vatican News reported that the Italian nonprofit Fondazione Rava will distribute the shirts to those in need.
Pope Francis urged people to continue to help the devastated region during his weekly Angelus address on Sunday.