Winter is traditionally read as rest, hardship or a time when growth goes underground. It can stand for emotional coolness, and also for the stillness that comes before renewal.
Has this come up in your dreams before? What was going on in your life then?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.