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.
Wave clouds above MItten Ridge in Sedona.
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).
Wave clouds over the San Francisco Peaks.
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.
Wide-angle view of wave clouds over the San Francisco Peaks.Zoomed-in crop showing structure of the wispy filaments with ACSL above.
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.
Wave clouds over Flagstaff.Wave clouds over Flagstaff.Wave clouds over Flagstaff.
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.
Observed sounding from KFGZ at 1200 UTC 02 July 202024-hour forecast sounding for KFLG for 1200 UTC 02 July 2020
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?
HYSPLIT backward trajectories.
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.
Water vapor satellite image from 1200 UTC 29 June 2020.
The moist layer had its origins along the Mexico coast. The water vapor image shows substantial moisture associated with Tropical Depression FOUR-E.
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.
Clouds over the San Francisco Peaks.Wave clouds above the San Francisco Peaks.
Time-lapse video of wave clouds and cap clouds.
And then there were these thin, wispy clouds catching the light of the setting sun.
A bit over a week ago (18 March 2018), we had a triple conjunction in the sky. Venus and Mercury had been in the evening sky for a few weeks—and now a crescent Moon was going to join them in the evening. Weather permitting, I was interested in capturing images of this event. I headed out towards the Mormon Lake Overlook which would give me a good view of the western sky as well as the possibility of reflections of these sky objects in the shallow waters of the lake.
While waiting for the sky to darken, I was treated to a few minutes of sunset colors on some interesting wave clouds. More on that below.
Conjuction of Mercury, Venus, and the Moon.
The Moon and Venus are easily visible in this image taken at 7:20 P.M. MST while Mercury is a bit harder to see to the right and above Venus. A second image taken at 7:29 P.M. shows all three bodies quite clearly. And, as I had hoped, there were reflections in the water.
Conjuction of Mercury, Venus, and the Moon.
This is how Venus and Mercury looked earlier in the month.
Venus and Mercury in the evening sky.
Now, back to the wave clouds.
Long and thin wave clouds in the evening sky.
Although they look like jet contrails, these were actually long and thin wave clouds. As the sun began to set, the colors were briefly quite amazing.
Sunset colors on wave clouds.Sunset colors on wave clouds.
It was an fun evening: Interesting clouds and a triple conjunction.
