San Juan Mountains Weather Report–Halloween– October 31, 2011–09:16–
Tuesday afternoon/evening we’ll see a fast hitting, but moderate storm along with a cold front moving through the San Juans and exiting Wednesday afternoon. Today (Monday) a similar day like Sunday with warm and abundant sunshine.
Today there is a Pacific shortwave over Washington state that will quickly dig a upper level trough tonight and move into western Colorado as an open wave Tue. night. The trough is supported by a cold front moving south from Canada & being pushed by gusty winds just ahead of the front. NW Colorado is favored with this small quick moving storm & the San Juans will probably see only a few inches of snow even in the alpine regions because of limited moisture.
By Wednesday afternoon the system should move east of our forecast area with clearing skies through Thursday then a strong trough of low pressure developing off the west coast will begin moving inland into the Great Basin and strengthening by Friday accompanied by a surface cold front. We will see snow Friday night through Saturday evening favoring NW facing slopes. As the storm moves east Sunday, there will be clearing with high pressure ridging.
No estimate of snow amounts yet, will have to wait for newer pressure/precipitation maps to make a guess.