We had an interesting wave cloud over and downwind of the San Francisco Peaks on Saturday. I first noticed it as I left the house driving to a trail run on Waterline Road in the San Francisco Peaks north of Flagstaff.
The view from the parking lot and trailhead was partially obscured by trees but I knew that sections of the Waterline Road had a wide-open view. And, so, I found a view that I really liked with the wave cloud, road, and distant cinder cones.
I shot this as a set of five vertical panoramas on my iPhone. I then imported these into Affinity Photo to create a horizontal panorama (a panorama of panoramas!). Finally, I used some warp transformation in AP to fix the horizon (i.e.; make it straight instead of curved) and the corners.
Earlier in the day the clouds were more extensive over northern Arizona but by early afternoon the sky was mostly clear with only occasional wave clouds appearing. These wave clouds were not terrain locked (i.e., remaining in place) but were moving quickly with the strong winds aloft. It is likey that they were generated by the Black Hills in Yavapai County.
The conversion of the original image to black and white helps to show the shape and textures of the cloud as well as the details of the cliffs and towers of Mitten Ridge.
A few weeks ago I captured these images of wave clouds over the San Francisco Peaks. At first, there was a “short stack” of lenticular clouds, specifically Altocumulus Standing Lenticularis (ACSL).
I took several photographs looking toward the peaks from the Bonito Park area near the west entrance of Sunset Crater Volcano National Monument. I alternated between wide-angle shots showing the snow-covered flats and zoomed-in images of the stack of clouds. After a few minutes, I was ready to leave.
But before I did leave, new clouds began to form beneath the stack of ACSL. These clouds were quite different and appeared as long, wispy filaments or rope-like clouds. Again, I took photographs ranging from wide-angle shots to zoomed-in shots. After about 8–10 minutes the delicate filaments began to take on more of an ACSL shape similar to the already-present ACSL above.
I was intrigued by the shapes of these clouds so I posted a comment with photographs to a weather discussion group with many atmospheric scientists far more aware of the dynamics and details of wave clouds than I. It turned into a fascinating discussion with links to journal articles, modeling studies and, inevitably, YouTube.
I do not think we reached a consensus on the dynamics and evolution of these cloud filaments but all agreed it was a worthwhile discussion.
For a few hours this morning (02 July 2020) the clouds were amazing. Laminar, wave-like clouds were visible across a portion of the sky and moving quickly to the north. Farther south, the sky remained clear. These clouds were apparently forming in a region of orographic uplift generated by the Mogollon Rim.
But these clouds weren’t actually a surprise. Yesterdays models were forecasting a thin layer of moisture around 700 mb with much drier conditions both above and below that level.
The GFS did a good job of forecasting both the thin layer of moisture and the stronger winds embedded in that layer. But where did those stronger winds and moisture originate?
A look back using backward trajectories from the HYSPLIT model reveals some interesting origins. Higher-level air parcels originated over the northeast Pacific while low-level parcels originated over the eastern Pacific. The water vapor satellite images shows both of these source regions to be very dry.
The moist layer had its origins along the Mexico coast. The water vapor image shows substantial moisture associated with Tropical Depression FOUR-E.
So the shallow mid-level moist layer had its origins in the remnants of a tropical disturbance. Very interesting!
New Year’s Day brought some interesting wave clouds to the San Francisco Peaks. I headed west to Brannigan Park to get both good views of the clouds and sunset colors on the peaks. In addition, I shot time-lapse video that shows the amazing motion of the wave cloud above the peaks and the cap cloud that obscures the summit.