The etymology of &#x27;winter&#x27;, as best can be determined, is &#x27;rainy season&#x27;.  So depending upon your local climate you might like to slide those three-month windows around a bit.<p>In my part of the UK November is <i>definitely</i> part of winter on that basis, which is why I like the Soltice-as-midpoint-of-season approach.