Hope you saw them and recorded them in your cloud and weather diary. I’m thinking that at the next Cloud Maven Junior meeting we should devote a lot of time to this issue. It was a rare day yesterday that the WHOLE day had that phenomenon occurring as aircraft penetrated those clouds, usually on ascent or descent. Sharp descents/ascents produce holes. See the sequence below if you don’t believe me (ppt from a recent talk):
Yesterday’s clouds: lots and lots of aircraft-produced ice
(btw, see note below about pop-up ads in this blog, ones that started to appear after downloading latest WP software)
6:44 AM. Altocumulus at sunrise. As we say so many times here in old AZzy, “So pretty.”Also at 6:44 AM. From a smartphone, color not so great, though not bad either.U of AZ Wildcats balloon sounding, launched at about 3:30 AM yesterday. Those Altcumulus clouds were way up there for Altocu, 22,000 feet above Catalina, 25,000 feet above sea level.because they were so high, were so cold, AND were composed of supercooled liquid water, they ripe for aircraft to create ice going through them, likely on climb out and descent from TUS and perhaps PHX as well, Davis-Monthan. What was unusual, was that it was happening most all day as the clouds filled in some. They remained liquid, high, and cold.7:23 AM. Wasn’t long before aircraft made their presence known in this cold, cold layer.6:54 AM. I should point out that a colder topped Altostratus layer was present to the N. Its not represented well in the TUS sounding. That layer was all or mostly all ice (the rosy colored segment of this photo).7:37 AM. An unperturbed view of Altocumulus perlucidus (“Mackerel sky”). Are there any mackerel left? Also, from a cloud viewing standpoint, these are much higher than one would guess. The fact that aircraft were making ice in them is a clue that they were higher than we would normally think of a “middle-level” cloud. I like patterns like this. I thought you would like to know that about me.9:03 AM. Slicing and dicing. An aircraft has left a contrail through a Altocumulus line . What’s really unusual here is the ice contrail so far outside the liquid water cloud. It is thought that hole-punch and ice canals are limited to regions where there are liquid droplets, and so this is quite an anomaly, one that suggests the humidity was almost 100% with respect to water outside the cloud boundaries. Also, can you just make out the partial 22° halo, indicating very simple ice crystals like columns and plates? Streamers of tiny ice crystals are also evident, trailing to the right, below the contrail? This shows that the wind decreased rapidly with height just below the flight level, but was still from the southwest to west.9:24 AM. Coming at you, another ice-canal has formed SW-W of Catalina, a favored locale for the formation of these canals on days like this.9:40 AM. What’s left of it is almost to Catalina. Note streamers of ice. Below, a close up of a couple.9:40 AM. The intensity and narrowness of these streamers point to an artificial origin. So, even if you didn’t see the canal, and here, some of the clouds are reforming at the top of the streamer, you would make a good guess that this was not natural ice. Sometimes the canals can fill back in if the air is in overall ascent at cloud level.9:57 AM. Here’s what those contrails in Altocumulus look like as they first appear. Can you spot’em? There are two.1:45 PM. Another aircraft-produced ice event as the Altocumulus increased and became thicker, making detection of these events less obvious. Sometimes a canal clearing is very muted.4:12 PM. Aircraft-induced hole punch cloud with ice below the hole. Can you spot it? See close up below.4:12 PM. Close-up of that hole punch, ice mostly below the Altocumulus layer.4:35 PM. That hole punch cloud 35 min later. The long trail indicates high humidity well below the Altocumulus layer in which it appeared.The 3:30 PM balloon sounding from the U of AZ. A study in ambiguity.The day ended with an unusually bright sun dawg, mock sun, or parhelia. So bright it did, again, suggest a plume of ice from a prior aircraft passage through extra cold Altocu or Cirrocu clouds. But, just wild speculation here. Hope you don’t mind.5:41 PM. Nice sunset, but one strongly impacted by clearing from aircraft-produced holes and lines of ice, the ice now mostly gone.
The End
——————About those nuisance ads—————
Note to me and the two other people that drop by my cloud or “clod” blogulations: The embedded pop-up ads are due to a WP third party plug-in that needs to be repaired. It will likely happen today.
After consultations about ads…
Oddly, those pop-ups and blue highlighting and double underlining do not seem to be present outside of my personal view of my own blog, this according to hoster, “godaddy.” Even using a different browser other than FIrefox does not show them as I have just verified.
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:
November 3rd
8:01 November 3rd. OK, I’m way behind! Flock of Cirrus uncinus overruns Catalina and environs.8:02 AM. Looking SW from Catalina. So pretty with the deep blue skies we have at this time of year due to sun’s lower angle in the sky.9:16 AM. Look how different, even unreal, that flock of Cirrus looked when leaving us. Looking NE toward the Charouleau Gap.
But the Cirrus kept coming and more odd sights were seen:
10:06 AM. Two levels of Cirrus can be seen. This vertical white patch is likely a few thousand feet lower than the crossing faint strands center and right side, which are likely above 30,000 feet above the ground. The heavier Cirrus (spissatus) in the distance is also lower than the strands.
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:
3:08 PM. Cirrus spissatus here, too splotchy in coverage to be Altostratus. Nice subtle lighting effect on the Catalinas…
“Due to time constraints, we move ahead in the action…”
November 4th
7:27 AM. Classic A row of Altocumulus floccus and castellanus underlie an Altostratus layer. Where the bases have disappeared, at right, are termed “floccus”, if you care.8:00 AM. Altostratus, some lower Altocumulus castellanus with graniteen boulders and a coupla saguaros.8:59 AM. Bird collective watches in hopes that the darkening, lowering Altostratus layer (with some Altocumulus) will bring rain. It didn’t. “Dang”, we say here.4:51 PM. All of the higher layers were gone, leaving only a lowest, but thin scattered to broken Stratocumulus clouds. 🙁 All in all, it was a good day for hiking and other outdoor activities.
Sunday, November 5th:
6:01 AM. Flock of CIrrus uncinus and spissatus again advances on Catalina.6:21 AM. a closer view. Here they seem to be uncinus with fibratus. Stratocumulus clouds were topping the Catalinas, too, indicating more humidity than we have been seeing most of the past few weeks.8:38 AM. I thought this was an especially spectacular scene, this lattice of Cirrus racing toward us. Hope you did, too.
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.
5:09 PM. Seeing this scene of Altocumulus, you KNEW you were in for a superb sunset. It didn’t disappoint.5:39 PM.5:40 PM. There is no virga here.5:44 PM. Super!
The weather just ahead
The Wildcat Weather Department model is foretelling perhaps a measurable rain event between this afternoon and tomorrow morning at 7 AM! Heavier rain is foretold to be south of us, but just a slight error would mean something more substantial. Hoping for error! A sky covering Altostratus layer is just about assured with a lowering tendency as the day goes on. Should see some Altocu , too, a day a lot like last Saturday.
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.
Yesterday’s clouds
6:42 AM. Altocumulus perlucidus at -11°C (12°F). No ice evident.6:43 AM. High-based Cumulonimbus erupts to the distant NW. Altocumulus castellanus layer from which it erupted can also be seen. The snow falling from cloud base is also evident, melting to rain just above the horizon.6:54 AM. By this time the full band to the NW whose tail was to pass over us about mid-day is evident. Plenty of snow can be seen falling from these modest, high-based Cumulonimbus clouds.
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.
Balloon sounding released from the U of AZ about 3:30 PM AST. Altocumulus clouds were no less than 21,000 feet above Catalina at -20°C (4°F). Sounding courtesy of IPS Meteostar. BTW, it wasn’t this balloon–see below.11:15 AM. A stationary balloon that hovers SE of Tucson. Can you find it? I had never noticed it before and at first thought it was in space, above the Cirrus! How crazy was that? Likely to be a device up there to monitor the US Border.2:55 PM. Cirrocumulus with an aircraft produced ice canal in it , tight half of photo (that ice cloud now termed, “Cirrus anthropogenitus”).4:02 PM. A complex sky for sure. Little tufts of Altocumulus way up at 21,000 feet above ground level, with Ac castellanus turrets (e.g., left above horizon). SInce those turrets are reaching up to temperatures well below -30°C (-22°F) they’re converting to all ice (such as center right). Those icy ones would be called, “Cirrus spissatus.” It would also not be untoward, and I know you don’t want that, to just call those deeper clouds with turrets on the left, “Cirrus castellanus.”
5:56 PM. Lines of Altocumulus make for an OK sunset.
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!
Nothing much else here of too much interest except the usual cloud blabber… haha
7:00 PM.7:04 PM. Hope you saw these!5:50 AM. Moon dodging clouds, Altocumulus ones. Moon dodgers? Did you know that the University of Washington sport’s teams were once known as the “Sun Dodgers”? How funny izzat? It’s truly amazing to me what you learn here.2:47 PM. Icy tops move toward the Catalina Mountains.3:54 PM. Not much going on over the Catalinas. But, can you spot the first ice from these clouds? You’d have to be pretty darn good to do that.3:54 PM. Zooming…. There it is! Have to look hard for the arrow and the bit of ice haze below that flat section. This would be a great ob day for an aircraft, since it would mark the threshold of temperature where ice is starting to form. Deeper, colder clouds from this threshold level would have more ice, a lot more. This level can vary from day to day, depending mostly on the sizes of droplets in clouds. With bases near freezing yesterday, this level would likely have been at the -12° to -15°C level, up around 20,000 feet above sea level. Bases were around 14,500 feet above sea level.5:23 PM. Nice lighting. I like lighting and lightning, no so much lightening, since a storm could be ending then, or if its around dawn, its OK. You can see two eyes, squinting….5:43 PM. Nice base streaming from Pusch Ridge enlarges as it came almost overhead! Looks promising for a SPKL. Moving car out from carport so’s I don’t miss a few drops.5:54 PM. Fine strands of rain now becoming visible!6:19 PM. Strands of rain in full display in RW-. Its measuring, not just a few drops! Need to roll up windows in car!7:13 PM. Not much happened just a little west of Catalina. Nice sunset, too.
Looks like another day for a chance of rain late….
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).
10:05 AM. Thar she blows! Just a spectacular jut from over the Mogollon Rim area, and a telling sign of what was immediately ahead for us.10:53 AM. Was doing yard work, under some trees, and then came out to see this amazing sight (Cumulus congestus erectus). Ran for camera, you have just seconds to a minute or two before it begins to fall apart due to entrainment of dry air that makes a cloud look ragged and frayed. Will it form ice? Is it cold enough up top? Should show up in a couple of minutes if it is going to.11:00 AM. Ice formation well underway as you can see by the frizzy, fibrous texture above the halfway mark up this cloud. At the time it seemed like it might be a big day for TSTMs with this kind of vertical rocket cloud shot so early. But, no. I would term this cloud, a Cumulonimbus calvus or capillatus, even though there is no visible rainshaft yet.11:00 AM. Going zooming…you can see that virtually this whole top is glaciated, and that fingerling, top left, shows some fallout of ice, likely aggregates of ice crystals. When concentrations are high, as would be the case in this glaciated turret, the crystals often lock together to form snowflakes. In cloud microstructure and modeling terminology, the stuff falling out would be termed , “precipitation ice”, and most of that in the fingerling, “cloud ice.” I hope you’re happy now.11:05 AM. An icy being seems to be leaping out of the new Cumulus congestus clouds that sprang forth so rapidly. That icy “being” is all that’s left of the original turret.11:09 AM. Kind of in the area of “beings” now. Those new Cumulus cloud sprouted up rapidly to fill the void left by our first cloud. But here it appear to take on the shape of a being waving, “Hey, look at my icy left hand!”11:52 AM. Thought this frizziness, texture of the ice made me think they might be “warm crystals”, that is ones that form at temperatures higher than -10°C, which would be needles and sheaths…. I sure wish I had a Learjet, get up there in a hurry, find out for sure…. The afternoon sounding supports that speculation with tops likely limited to those higher temperatures, but not the morning one12:49 PM. One Cumulonimbus calvus stage here, was potent enough to produce a bit of thunder, maybe the last we’ll hear for many days.1:00 PM. Looking to the west, you could see the drier air moving in as evidenced by the lack of any buildups for as far as you could see, and also in the pitiful clouds over the Tortolita Mountains. It was a hard time, knowing the end was at hand. And there it is, below:
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:
9:40 AM. Like most of our summer days, it begins with mid-level layers of Altocumulus, in this case shown here, “translucidus” variety (rather thin, it is.) It was up around 13,000 feet above the ground, if you care.11:07 AM. As the Altocumulus clouds thinned, burned off, the rise of the Cumulus begins, here a gigantic one spurts upward telling you that there are going to be some blasters yesterday. Very exciting to see this. I can feel your heartbeat as you, too saw it.11:51 AM. Wasn’t long before giant Cumulonimbus clouds were dumping over there on the town of Oracle. Nice town it is, btw. However, these clouds weren’t much electrified, telling you that the updrafts weren’t particularly strong yet, even though tops here were probably pushing around 30 kft.11:52 AM. Cumulus congestus, and Cumulonimbus calvus start unloading over there toward I don’t know where exactly, but its just on the other side of the Tortolita Mountains. You’ve probably noticed how clear the sky has been, completely free of haze. That’s good for rain production, since the cleaner conditions are the larger the drops can be in the clouds because there are fewer of them compared to clouds forming on hazy days. Nat King Cole sang about summer haze as early as 1963, so we know that haze is not a new thing, like CO2 is. You won’t find people singing about CO2 in ’63!11:58 AM. The three amigos…. A slight rain shower can be seen in the slight haze in front of the mountains below the center Cumulus. Tops of these spindily Cu leaned way out again due to weak updrafts and and stronger winds aloft from the S. Since rain forms in the upper portions, it fell a little away from the mountains in these weaker Cumulus.12:02 PM. Dump truck, fully unloading! Not messing around anymore here. With cloud bases running around 15°C (59°F) there was a ton of water up there. Well, thousands of tons.12:06 PM. I know what you’re thinking: “Oh, look, a baby dump. Isn’t it cute!” Suggests an abnormally narrow turret poked to far higher altitudes that those around it.12:24 PM. More Cumulus congestus clouds joined the fray and this became a major 2 inches or more producing system over on the Tortolita Mountains.1:01 PM. Now the outflow surge can be seen on the left, pushing new Cumulus turrets above it. This was about the peak of it, as it gradually wound down. Its certain that flash flooding occurred with at least 2 inches having fallen in the core.
Well, the day closed on a disappointing note as Cumulonimbus debris clouds overspread the sky, killing new convection.
5:45 PM. Altostratus “cumulonimbogenitus.” The day went quietly into the night.
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!!!!
5:47 AM. Two layers are visible, a distant Altocumulus castellanus one, and the higher, much higher, cirriform clouds resembling Altocumulus. If you don’t believe me, the sounding from the U of AZ is below.The TUS balloon sounding for 5 AM AST yesterday. The Altocumulus patches were up around 16,000 feet, and the cirriform clouds around 33,000 feet and at about -50°C (-58°F). Had to cuss that bit because I sensed some doubt out there.6:38 AM. Same cloud layer. Seriously, how can you not call this “Altocumulus”, it mimicks it so well. But these globules are all ice, no liquid water of course anywhere near -50°C unless we believe the reports of Simpson (1963) who purported liquid at -62°C. Nobody believed him though; me ,neither.7:37 AM. Another view of this cirriform layer making a mockery out of Altocumlus. Note that there is that tiny bit of shading, too, in these cloudlets.5:24 PM. The convection leading to cellular structure was still evident pretty much the whole day. Again, we have a problem. Shading like this is not officially permitted with in cirriform clouds except in the “spissatus” species. One would be thinking “Altostratus” here since that cloud is widespread and can have gray shading. When you look at the TUS sounding nearest this time, you find that the moisture is still contained in the upper reaches of the troposphere, where it was in the morning, and that would be in the “etage” for high clouds, 30,000 feet or so above sea level.The TUS balloon sounding for 5 PM AST, May 25th. The temperature of that icy layer ranged from about -35°C on the bottom to -60° C at top, so there would not be any liquid water in it even though is might appear in some places. Where’s my Lear jet? Need to check these things out and in a hurry!
Haven’t had much to say, brain pretty empty again after the big review of the NAS 2003 review which really needed reviewing and commenting on real bad….
(More “late homework” in the offing.)
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Nice sunset last night; we have had a series of pretty nice ones over the past few days.
April 26th. Sunrise over the Charouleau Gap.Orangy mountains highlighted by a gap in the Altostratus layer that allowed the setting sun to shine through.7:04 PM. There was some turreting in this line of Altostratus that passed over, and because of those deeper tops, indicating stronger, if still slight updrafts, larger snow particles developed and produced this line of heavier virga underneath it.7:10 PM.A contrail that’s more than about ten minutes old, now, after the new Int. Cloud Atlas has been released, termed, Cirrus anthrogenitus, maybe castellanus in this case, too.
From IPS MeteoStar, this interesting map for tomorrow morning.
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.
Map valid for tomorrow morning at 5 AM AST.
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:
Valid at 5 PM, May 2nd. Nice!
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:
11:27 AM, January 2nd. The ice canal in the middle of an Altocumulus layer that might in the future be termed a Cirrus altocumuloanthroglaciogenitus.
5:53 PM. An example of the various cirriform clouds we’ve been treated to the past week or two, ones that have been giving us those nice sunrises and sunsets. Doesn’t seem like there’s been a cloud below 50,000 feet for about that long, too. (I’m exaggerating just a little.)7:04 PM. Seems like sunsets are occurring later and later. Here the setting sun allows some of the “topography” of Cirrus clouds to be accentuated.
The End
——————————————- 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.
