A smoking mountain might seem an odd topic during a wet spring. However, the title does not refer to a wildfire, but to the name of a weather phenomenon.
Sometimes a cloud streaming off the lee of a mountain has the appearance of smoke from a wildfire. This is most likely to be seen when: the mountain has a fairly sharp ridge line; there is a brisk wind flowing across the mountaintop; the valley on the lee is deep and the air in it is moist.
The wind flowing across the mountain top does not follow the terrain. The sharp mountaintop causes air to separate from the surface and carry on high above the valley. However, this wind drags air in the valley with it causing it to flow in the same direction. This, in turn, causes air to flow up the lee of the mountain. As the moist air is lifted, a cloud forms, giving the impression of smoke pouring off the mountainside.
Streamlines have been added to the picture to illustrate the wind: the air above the mountain top is flowing from right to left; on the lee side of the mountain, a cloud forms as the moist air is lifted. The cloud has the appearance of smoke from a wildfire. To see the picture without the streamlines, roll the cursor over the image (computer), or tap on the image (mobile device).