Doesn’t happen every November, thunder, but it sure pounded away at times yesterday. Seemed louder than usual thunder a few times even with the lightning over there by the Tortolita Mountains. Of course, that’s where the heaviest rain fell as several T-storms tracked along a similar path over there just a little to the W through N of us, Bio2, in one of the heavier cloberations receiving 1.17 inches.
Here, in The Heights, we received a disappointing, but nevertheless welcomed final total of 0.24 inches. This brings our total here in Sutherland Heights for November up to 0.60 inches. Average is 0.96 inches
1. Here, the regional totals as the storm was coming to an end:
“Us” is here in the Sutherland Heights; “Them” is Bio2. Wanted to reflect the general world situation now days by using oft used cliché terms.
As is proper, let us begin examining the nubilations of our storm by looking at those clouds that preceded the actual rain day yesterday.
7:02 AM. This pretty sunrise over the Catalina features a couple of flakes of Altocumulus clouds, and a vast layer of Altostratus.
7:04 AM. Yes, the sun is coming up, though really its the earth rotating toward the sun. The sun does not go around the earth every day; it only SEEMS that way. We’re looking at the same two cloud generas, btw. Nice rays produced by pretty regular humps in clouds over the horizon, a little row of Altocumulus castellanus might cause these rays/shadows.
7:05 AM. This was pretty interesting, to use “pretty” again. This would be an Altostratus mammatus. Men often find this formation especially interesting and pretty. Here you can also see how a cloud protuberance can produce a shadow. But why is there only one feature like this? Typically mammatus are like upside down Cumulus turrets representing downward moving cloudy, in this case, air filled with ice crystals). Adjacent to this feature, the ice crystals and snowflakes are just settling out. As the moving downward air in mammatus features slows, these breast-like globules open up and you’ll have ordinary virga. The ice crystals are typically rather small and not rimed (that is, have not collided with cloud droplets) or they would fall out and not be constrained to this pretty, rounded shape.
7:07 AM. The underside of the Altostratus is lit up, showing the detailed areas of virga. Altostratus, by definition, is a precipitating cloud. Its just that the bases are too high for the precip (snow) to get to the ground, though sprinkles could occur in the thicker, deeper versions. When and if it starts to rain steadily, the cloud is better termed a “Nimbostratus,”
11:20 AM. The Altostratus deck departed with its pretty mammatus and virga, leaving great examples of Altocumulus opacus clouds most of the morning and into the early afternoon.
3:24 PM. An example of Altostratus translucidues doesn’t get better than this. Hope you captured it. The As (abbrev. for “Altostratus”) cloud over took over by mid-afternoon as the moist layer deepened again following the Altocu. Tops of this all ice Altostratus layer, in spite of being able to make out (“discern,” not “make out” in the social sense of the phrase–still thinking about that mammatus formation) the sun’s position, are usually around Cirrus levels, the top of the troposphere. The TUS sounding suggested “bases” (actually where the ice crystals are evaporating rather than droplets that comprise the bases of Cumulus, Altocumulus or other droplet clouds) at 14,000 feet ASL, and tops around 34,000 feet ASL Subtract about 3 kft to get heights above the ground here in Catalina.
Moving ahead to yesterday…..
7:13 AM. With an approaching upper level trough and big low center in the Great Basin, the winds had become gusty, and the clouds had lowered to Stratocumulus status, topping the Catalinas. I thought the lighting was really pretty here, and that shaft out there shows that turrets are climbing shooting up well beyond the general tops of the shallow Stratocu. Pretty exciting since it meant that the tops of other Stratocu might bunch into other Cumulonimbus clouds, which is what that shaft tells you.
8:18 AM. A line of Cumulonimbus quickly erupted and it looked like it was about to crash into the Oro Valley Catalina area, but instead stayed to the west over the Tortolitas. Thunder heard!
8:19 AM. Looking WNW toward the Tortolitas.
9:27 AM. As some light showers passed along the Catalinas, this pretty scene the sun broke through. Note the glistening rocks that added such pretty highlights.
9:28 AM. Pretty nice over toward the Gap, too! I will never get tired of these scenes!
11:12 AM. Disappointingly, in view of all the rain predicted here (0.575 inches) that first line of Cumulonimbus clouds stayed stayed west of Catalina. But, that line of Cumulus or Stratocumulus clouds on the horizon is full of stormy portent, that a windshift line might be about to strike and generate another line of Cumulonimbus clouds. Any solid line of clouds like that, kind of by itself, suggests a windshift; it more than just a fair weather “cloud street.”
11:11 AM. Zooming in on that line of clouds. Its fun to zoom, since you are in a way, flying toward what you’re looking at, getting so much closer! I wish that line of clouds was here already!
11:27 AM. Yep, there it goes, fattening upward into Cumulus congestus and to the N, Cumulonimbus clouds! This one will surely blast across Catalina as the upper trough and associated cold front approach; heck, maybe that’s the cold front windshift line and temprature drop right there!
11:27 AM. Yep, there it goes, fattening upward into Cumulus congestus and to the N, Cumulonimbus clouds! This one will surely blast across Catalina as the upper trough and associated cold front approach; heck, maybe that’s the cold front windshift line and temprature drop right there! Repeated for emphasis.
11:29 AM. A Cumulonimbus cloud is a bit farther north in this line. This HAS to be the windshift and cold front!
11:46 AM. Was inside for a few minutes (18) and that cloud line just exploded over there. Here looking again toward the Tortolitas. But surely they will wall out and crash the sunny party in Oro Valley (I was thinking).
11:52 AM. Well, these followup Cumulonimbus clouds aren’t looking so great, no evidence of strong turreting, weak and leaning, wispy, frail, “indolent”, cloud “couch potatoes.” Hope fading for a big shafting here in The Heights
12:12 PM. The cloud line, as expected is progressing across Oro Valley, but shafting is meager. Its real windy, though, adding some drama. Gusts to 40 mph! Note however the weak shafting, as evidenced by a slope across the whole thing; no heavy, large particles falling out of this guy as we see in those vertical summer shafts. Indicates that the tops are getting very high, producing lots of condensate. So even here, with a nice dramatic scene, you’re thinking (to put words in your brain) that its going to be a disappointment in rain production, and you might be missed altogether!
12:24 PM. It was pretty much all over 12 min later, that is, the chances for a real shafting. A well formed Cumulus congestus base formed just upwind of Catalina, but as so many do, slipped a little east before reaching Cumulonimbus stage and unloaded on the Catalina foothills NE of Catalina. Sometime, when clouds like this are overhead and show no precip, it just can dump out of the black. But, it didn’t happen yesterday. By now, the wind had shifted, the temperature was falling, and soon, the light to briefly moderate rain fell as the cold front went by.
1:14 PM. By this time, you could pick up a couple of nice photos of just Stratocumulus clouds following the passage of the front. Here we see some indications of mammatus formations (upper center, right) in a droplet cloud, an extremely rare event since droplets evaporate so much faster in downward moving air that the pouches represent. One can surmise that those pouches may have contained higher amounts of liquid water, and the downdrafts were very slight. OK, so we’re kind of fixated on mammatus today…. No apologies; I’m just a man.
The great thing about yesterday was that because the upper trough lagged so much behind the cold front, you could be sure it wasn’t over, that is, the rain chances. In fact, as the wind turns aloft from a southerly or southwesterly direction to a more westerly one, we here in Catalina have a better chance of having the clouds pile up over us, even if they’re not full fledged Cumulonimbus clouds, they can still reach depths where they precipitate while upwind, they don’t because they may not be deep enough. The Catalina Mountains provides the lift that helps do this, and we saw that happen later in the afternoon and evening when it began to rain again long after the cold front and it so-so rain band went by.
3:06 PM. Starting to look more favorable for rain and the clouds began to cluster after the boring spell of Stratocumulus except for the brief display of pretty mammatus. The air aloft was getting a little colder, too, helping the Cumulus clouds deepen upward in spite of cool temperatures following the front. This view is looking upwind to pal Mark Albright’s house there in Continental Ranch, Marana. Mark is a fellow U of WA research meteorologist, though he hasn’t thrown in the towel yet, is still working.
3:34 PM. Even as the clouds filled in and the light showers began, some pretty highlights were observed where the sun peaked through holes in the overcast. Here, Eagle Crest to the north of The Heights is spotlighted. If you are a resident of Eagle Crest and you would like a copy of this photo entitled, “Spotlight on Eagle Crest”, you can get one today for $1200, If you call now, you can get two for $2400.
5:25 PM. FInally, as the light rain fell, adding a few more hundredths to our total, sunset occurred! You can see it WAS raining by the drop on the camera lens, I didn’t just say it was raining because I wanted it to. Note the lack of shafts. This tells you the tops of the clouds are pretty uniform, not protruding much above us. The rain was “pretty” steady, another indication that the clouds are relatively uniform in the horizontal.
The End, FINALLY!
1If we don’t get more rain by the end of November, I will delete the sentence of a week or so ago stating that November would have above average rainfall. No use having people see that.