For the cooler, darker months of October, November, and December I've been spinning a lot of:
Amorphis (Privilege of Evil, Tales From the Thousand Lakes, Eclipse, Skyforger, Halo, Borderland)
Moonspell (Irreligious, Darkness and Hope, The Antidote, Extinct, Hermitage)
Opeth (Orchid, Morningrise, My Arms, Your Hearse)
Katatonia (Brave Murder Day, The Discouraged Ones, Tonight's Decision)
Tiamat (The Astral Sleep, Clouds, Wildhoney, A Deeper Kind of Slumber)
Anathema (The Silent Enigma, Eternity, Alternative 4)
Lake of Tears (Greater Art, Headstones, Forever Autumn)
and a little:
Agalloch (The Mantle, Ashes Against the Grain)
Paramaecium (Exhumed of the Earth, Within the Ancient Forest, Echoes From the Ground)
Empyrium (A Wintersunset..., Songs of Moors and Misty Fields, Weiland)