Been busy as a briefly unretired science worker (gave a stressful talk at a university last week) and thought maybe a lot of usual drop ins to this site might not anymore. So, in the title for today, am reaching out to a new demographic: persons interested in congealed soil matter. They might later, after stopping by, discover a new interest; that in clouds, pretty ones. Most of the cheap tricks I try like this don’t have any effect, though. Oh, well.
Let us go forward after backing up:
But the Cirrus kept coming and more odd sights were seen:
Heavier Cirrus, increasing and lowering to Altostratus finished off the day as a heavy shield of middle and upper clouds raced toward southern Arizona from the Pacific:
“Due to time constraints, we move ahead in the action…”
Sunday, November 5th:
4:26 PM. Perhaps the brightest example of iridescence I have ever seen! Just spectacular for a few seconds in this patch of Cirrocumulus. Iridescence is caused by diffraction around the tiny of droplets, less than 10 microns in diameter, as are present when a cloud just forms.
A trace of rain was officially recorded in Catalina at this site ending prospects of a rainless October. It fell from high-based Cumulonimbus clouds in a band, partially lining the NW horizon that could be seen as the sun rose yesterday. Some ants were injured by the falling drops, ones that reached millimeter sizes and fell at 5-8 mph, though in some areas, winds of 10-15 mph added to drop impacts. Flying insects, while obliged to avoid the watery missiles, were able to do so with ease due to the appreciable spacing between the drops of several feet.
Due to the short-lived hydrometeor events, many humans were unaware that rain had fallen in Catalina on more than one occasion yesterday. That’s why we blog here. Weather and cloud news you can rely on.
How high were the bases of those precipitating clouds spewing snow virga that melted to rain? Higher than the freezing level! Haha.. The balloon sounding profile started with the Altocumulus perlucidus layer at 18,000 feet above sea level, 15,000 feet above Catalina, bases at -11°C. By evening the lowest moist level had lowered to 14,000 feet ASL (11,000 feet AGL) and -3°C. However, that last moist level had to be a bit lower than those snowy cloud bases IMO–we know that the moist level almost always lowers.
So cloud maven person will make the definitive call that the rainy (well, sprinkly) cloud bases were at 16,000 ASL (13,000 feet AGL) when they passed over, if that makes any sense or is anything you really care about.
As rain fell……this sky, 12:30 to 1 PM:
Kind of pathetic really; no shafting whatsoever, much less virga than on the horizon yesterday morning. So our end of that band was so weak it was just barely able to get some drops to the ground.
Looks like this is it for rain in October 2017. However, November 2017 appears to look much brighter for substantial, dust-removing rains in Catalina beginning in the first 10 days!
The End (I missed the sunset due to a social engagement–hope you saw it wherever you were). Probably was pretty nice.
Another pretty cloud day ahead. Though most of the Altocumulus clouds are flat, there are some whoppers off to the north now, Ac cas so large they might have to be called Cumulonimbus, certainly large enough to produce radar echoes, maybe a sprinkle at the ground.
Lots of wind tomorrow, as you likely know, but no rain in sight still. So, October almost surely will end as a rainless month. Our average for October is just over an inch of rain!
Not much going on lately, so will dip into the archives from two days ago. One cloud in particular was so spectacular in its defiance of gravity, rocketing upward the morning of the 4th. So here are shots from that day…
6:46 AM, Aug. 4: The day began with a pretty normal looking patch of Altocumulus perlucidus (honey-comb pattern). No virga, so its likely not too cold. The sounding suggests it was up at 16,000 feet ASL, or 13 kft above Catalina at about 0°C (32 F).
Now, that’s pretty funny. We specialize here in too much said! Its a niche thing. Of course, not enough can be said about our past July. Take a look:
This, of course, was a new July rainfall record for Catalina/Sutherland Heights going back to 1977, anyway. Had to adjust vertical axis of this chart, too. Formerly, it stopped at only FOUR inches! The moon lore was right! It’s interesting how the ancient lore of early peoples that I made up a month ago was more accurate than the Climate Prediction Center’s prediction of an equal chance of above or below normal rain in southern Arizona while something incredible was on the doorstep! Kind of like last winter in the whole West where record amounts of snow and rain piled up over a huge region, and that, too, was also unforeseen “going in.” Think how horrible it would be if those predictions were always right. Sure, billions could be saved by such accurate outlooks, but then the element of surprise would be gone. How bad would that be?
After the paucity of rain in the preceding five months, and with June carrying into around July 10th this year with its blazing heat and no clouds, all that rain that followed with thunderations day after day, the attendant rain-cooled “breezes” to 50 mph on occasions, blowing stuff all around everywhere, were sure welcomed (?). (Another case of innovative punctuation to emphasize a point, whatever it is.)
Let us begin today by examining the greenth of the 2017 summer on our Catalina Mountains so far, thanks to July’s copious rains. Hah! The climate really has changed. Looking into growing bananas now…Now for some cloud photos from yesterday:
Well, the day closed on a disappointing note as Cumulonimbus debris clouds overspread the sky, killing new convection.
The weather way ahead
Looks like below average rain for August. :(, as we say. Hoping for error here. Average August rainfall here in Catalina/Sutherland Heights is 3.16 inches.
Later yesterday morning, some interesting “Altocumulocirrus”, a rare breed indeed, mocking/mimicking Altocumulus.
Maybe Cirrus floccus would come closest to the true name, but to every eye but that of a genuine cloud maven person, it would be deemed just “Altocumulus”. Check these out to see how good you were–and NO correcting your cloud diaries!!!!
The orangy colors denote the strongest winds in “Jetty Jetstream”, and as you know, the colder, low clouds, ones capable of reaching the temperatures where ice forms, are contained within that ring of strongest winds at this level (500 mb). So, while the models I have looked at so far have no rain here, I think there’s a pretty good chance of a rogue shower tomorrow morning anyway. At least there should be some nice Stratocumulus/Cumulus tomorrow and some will have ice in them. As you know, it’ll be awful windy today, too, maybe 40 mph or so in brief gusts here in The Heights of Sutherland.
Also will be looking for some nice lenticulars since “Jetty” will be right over us, but a little toward the warm side where lenticulars mostly occur.
In the meantime, spaghetti suggests a big trough in our area again about nine days from now. The later ACTUAL model outputs don’t show much of anything. What’s up with that? I’m hanging with spaghetti that later model runs will indicate a strong trough, and at LEAST another pulse of cooler air, and another minor chance of rain as we are going to see today and especially tomorrow as when become within the “ring of winds” aloft. Didn’t Johnny Cash sing something about that? Maybe it was Wall of Voodoo…
Below, some spaghetti for you showing a big trough over Arizona and the Great Basin which is not much reflected in the actual models, as noted. But, just watch my friend, how those model outputs will change to reflect a bigger trough about this time!
April’s been kind of a weather dud here in Catalina so far (no rain so far, and the chance on the 20th, mentioned here some weeks ago, has receded to Utah and points north), so lets take a look at how May is shaping up, only two weeks ahead:
I thought you’d be pretty happy when you saw this, as I was.
Its possible there is a photo from Catalina, Arizona! I have not checked yet. Its just been published by the World Meteorological Organization of the United Nations. Still needs a little work, but overall is VERY, very nice. Came out out on March 23rd, so we’re a little behind here as usual. The thing that makes it different from prior and sometimes flawed atlases is that each photo is accompanied by some weather data and in many cases maps, radar or satellite imagery at the time of the photo.
Some new expressions to toss around to your fellow cloud-centric folk are things like “Cirrus anthrogenitus”–Cirrus evolved from contrails and “Cumulus flammogenitus”, a Cumulus formed at the top of a fire, something we used to call, “pyrocumulus”, an unofficial term that somehow seems preferable to “flammo”.
However, something that has drawn great attention over the past 20 years or so was not given a name, aircraft-produced ice in Altocumulus and Cirrocumulus clouds, which have been referred to by Heymsfield and colleagues as “hole punch clouds.”1
Ice canals amid Altocumulus are also fairly common. Ironically, a hole punch cloud with ice in the center, and an ice canal in an Altocumulus cloud layer can be readily seen on the new International Cloud Atlas submission site, now closed. They’ve mistakenly, IMO, referred to “ice canal” photos as “distrails” without mentioning the ice canal “cirrus” down the middle. Formerly, distrails were clearings produced by aircraft in thin clouds without any change of phase in the cloud induced by the aircraft, unlike those holes and clearings produced when the ice-phase is triggered by an aircraft passage.
Certainly a “hole punch” cloud is not a distrail, a linear feature, and should have a separate nomenclature.
In keeping with the new terminology regarding “anthro” effects, maybe it should be, since we’re talking about the Cirrus induced by an aircraft, albeit at much lower levels than true Cirrus clouds:
“CIrrus Altocumuloanthroglaciogenitus.” (??)
Here’s a classic one of those that erupted over Catalina, posted here last January:
——————————————- 1It should be pointed out immediately if not sooner that Catalina’s Cloud Maven Person had plenty of time to rectify, or suggest changes to the Atlas as he could have been part of this process, but didn’t really do anything except submit some images for consideration.
In particular, those Altocumulus clouds, “cold” Cirrocumulus (ones that transform to ice immediately), and those “Altocumulocirrus” clouds combining with scenes of “regular” cirriform clouds. Lots of interesting sights to have seen yesterday. All these the result of marginal moisture aloft and strong winds, up around 100 mph at the highest Cirrus levels.
Let us begin as cloud maven folk by examining the late afternoon sounding launched from our Wildcat balloon launching machine at the University of Arizona, courtesy of IPS Meteostar:
The weather way ahead
Still looking for that chance of rain before July…. haha
Troughy conditions will actually recur aloft over us over the next few weeks it seems, which means slight chances of rain, but periodic cold fronts passing by, mostly dry ones. Best chance for rain still seems to be around the 20th, plus or minus a day or two, even though mod outputs have backed off that scene. But, we have our spaghetti that tells us the models will likely bring back that threat around the 20th, even if some individual runs show nothing at all or only close calls. We shall see if this interpretation has any credibility at all, won’t we?
Of note, Cal having big April in rain and snow after the gigantic January and February accumulations! Looks like they’ll continue to get slugged by unusually strong storms, off and on, for another couple of weeks. Water year totals are going to be truly gigantic.