We saw a large, long, dusky cloud in the northwest horizon, which was snowing, when all the rest was clear sky.

December 2.

When I first saw that snow-cloud it stretched low along the northwest horizon, perhaps one quarter round and half a dozen times as high as the mountains, and was remarkably horizontal on its upper edge, but that edge was obviously for a part of the way very thin, composed of a dusky mist which first suggested snow. 

When, soon after, it had risen and advanced and was plainly snowing, it was as if some great dark machine was sifting the snow upon the mountains. 

There was at the same time the most brilliant of sunsets, the clearest and crispiest of winter skies. 

We have had every day since similar slight flurries of snow, we being in their midst.

H. D. Thoreau, Journal, December 2, 1858

See November 30, 1858 (“We saw a large, long, dusky cloud in the northwest horizon, apparently just this side of Wachusett, or at least twenty miles off, which was snowing, when all the rest was clear sky. . . .Thus local is all storm, surrounded by serenity and beauty”)