I live on an open plateau (1,850 ft.) barely north of the Presidential Mountain Range in New Hampshire. One of the pleasures of being up here is witnessing the interaction between the mountainous topography with the sky/weather.
My favorite cloud formations are Orographic Clouds. The most basic definition says that they are formed by air being forced upslope. Click to learn more
I have plenty of good quality photos of this cloud type but would like to share some from one particular evening, April 17th 2009. The reason being that there were several of them whose formation took place at the same time. Some actually traveled over a lengthy period of time, moving across the valley from the Carter-Moriah Range over to the Presidential’s. In my case, Mt. Madison.
[*Note, I do have a question as to the creation of a stratus cloud(s) during this time? It was so thick that it appeared to be a solid wall, literally swallowing the sun. It was also at a perfect 90 degree angle to the Orographic display and so close that I placed one foot inside and the other outside of the cloud at the same time. Inside this stratus was nothing but moisture and a few feet visibility.]
These photos were taken with film which is great but I didn’t properly store the photos. I “processed” them with Photoshop, leaving some of them a bit saturated and just for fun used the program’s choice of “levels” on all of them. Most of them were pretty close but some were rather interesting and are included with the others as duplicates.
This summer I saw a rare Orographic formation while driving home. They are Kelvin-Hemholtz Waves and from what I’ve read they form quickly and don’t last long which was my experience. I happened to have my camera with me but it was almost dark and so little time. The formation dissipated in about one and a half minutes.