The route to the border city of Tijuana is still about 1,550 miles (2,500 kilometers) away.
Whereas the migrants suffered from the heat in southern Mexico in mid-October, they now trek to highways wrapped in blankets to fend off the morning chill.
Migrants gathered Monday on a highway leading out of the central city of Irapuato and looked to climb aboard trucks to take them to Guadalajara.
Honduran migrant Karen Martinez started walking with her three children bundled against the cold.
Martinez said: “Sometimes we laugh, sometimes we cry, but we keep on going.”