We have observed that Poul Anderson's "Star Of The Sea" includes passages of mythological writing and of historical fiction and also that several of the latter begin by describing seasonal changes. Here by contrast is the opening sentence of a mythological passage that begins with the transition not from winter to spring but more fundamentally from night to day but which also invests this naturally recurring event with mythic significance:
"Out of the east, the morning behind them, rode the Anses into the world." (Time Patrol, p. 557)
Remember, new gods coming from the east with the sunrise. I have attended Pagan ceremonies where we each speak and drink from a horn of mead before passing the horn around the circle. At such ceremonies, I have recited Poul and Karen Anderson's "Tene Mithra, etiam miles, fides nostris votis nos," (see here) and will in future recite, "Out of the east..."