Luke 24:1-3 1 On the first day of the week, very early in the morning, the women took the spices they had prepared and went to the tomb. 2 They found the stone rolled away from the tomb, 3 but when they entered, they did not find the body of the Lord Jesus.
So if they are getting there "very early in the morning", and the tomb is empty, there's a pretty good chance that Jesus exited, stage left, BEFORE the sun was up! Hence, no shadow. Meaning Spring has sprung!!