He shared their wrath because the hostile Northern foot already pressed a portion, and he felt as much eagerness as they to drive away the invader.
He also saw pretty soon that the long lines of the mountains, so blue and beautiful against the shining sun, were losing their clear and vivid tints.

The sky above them was turning to gray, and their crests were growing pale.

Then a wind chill and sharp with the edge of winter began to blow down from the slopes.

It had been merely playing at summer that morning and, before the first day of January 1862, closed, winter rushed down upon Virginia, bringing with it the fiercest and most sanguinary year the New World ever knew--save the one that followed it, and the one that followed that.
The temperature dropped many degrees in an hour.

Just as the young troops of Grant, marching to Donelson, deceived by a warm morning had cast aside their heavy clothing to be chilled to the bone before the day was over, so the equally young troops of Jackson now suffered in the same way, and from the same lack of thought.
Most of their overcoats and cloaks were in the wagons, and there was no time to get them, because Jackson would not permit any delays.