The clouds first assignment is intended to get students to start looking at clouds and taking note of the different types and weather conditions that cause them. Clouds give a good indication of the state of the atmosphere and the flow that they demonstrate can be very complex. The image highlighted in this post was taken in Golden, CO at 1926 on 6OCT18 while between the hogback and the foothills. The image is looking towards the west so it can be clearly seen that the waves of clouds are running parallel to the Front Range.
The clouds show here are Altostratus Undulatus. This picture was taken the night before a large storm reached the Denver area so the atmosphere was very wet at the time. It was also a stable atmosphere which created some very unique clouds for the region. The atmospheric data can be seen in more detail in the Skew-T chart below:
The two dark lines are nearly parallel for every elevation indicating that the air had a large amount of moisture. This makes it difficult to estimate the elevation of the clouds based on the Skew-T alone but using other data from the nearby regions, I think that these clouds were at an altitude of approximately 4000m above ground level. Altostratus Undulatus often form immediately preceding pockets of unstable air and storms and are good indicators that the weather will be changing within the next day. The wavy affect is created by gravity waves, similar to ripples in a ponds but on a much larger scale.
This image was captured using an Apple iPhone 7 at an aperture of f/1.8. The shutter speed was 1/4s to allow as much as light as possible to be captured by the sensor since the conditions were fairly dark. The focal length was 3.99mm and the ISO was 1600 which caused some graininess to be apparent but not so much as to be overly distracting. The resolution of the image is 4032X3024 pixels. Some modification to the image was done in post processing to reduce the grain and to recreate the colors that were actually visible that night. The camera seemed to removed the red hue of the clouds so that was added back in after the image was taken. See the image below for the unedited file.
Overall I am happy with how this image turned out. It shows an effect not often seen in this region and the coloring gives it an otherworldly feel.
One of the aspects that I would have liked to have changed would be that I would prefer to have taken this with a dedicated camera rather than the iPhone. I think that would have given better resolution and less grain as I would have been able to adjust shutter speed and aperture manually. Unfortunately I did not have my camera with me at the time so I made the best of my available resources.