We survived yet another month of weather in October and now we look toward a new month of surprises in November. Halloween was excellent weather for trick-or-treating and other outdoor events. Remember that one.A cold air mass made its advance toward us late Wednesday with some showers and chilly temperatures. We will see periods of rain and clearing today through the weekend. Not a total washout by any means, but you will definitely feel the change in the air mass. Lots of cold air developing in Canada.Snow is falling today in the Cascades and Olympics and will begin to dust the upper reaches of the coastal mountains tomorrow. It is possible, if things set up just right, the upper ski areas will get 2 or 3 feet of snow between now and next week.If this was four or five weeks from now, we would be flirting with snow here in the lowlands. But it is not, fortunately. At least we begin to build a mountain snowpack and maybe, just maybe, open the slopes for Thanksgiving skiing.Beyond the weekend into next week, we have a short break Monday and Tuesday but another storm by Wednesday with more snow in the mountains. With freezing levels low, we will see some snow east of the mountains in central and eastern Washington and Oregon. Factor that in if you are traveling. Patrick Timm is a local weather specialist. His column appears Tuesdays, Thursdays and Sundays. Reach him at http://patricktimm.com.