About real clouds, weather, cloud seeding and science autobio life stories by WMO consolation prize-winning meteorologist, Art Rangno
Author: Art Rangno
Retiree from a group specializing in airborne measurements of clouds and aerosols at the University of Washington (Cloud and Aerosol Research Group). The projects in which I participated were in many countries; from the Arctic to Brazil, from the Marshall Islands to South Africa.
Clouds got more enthusiastic than expected here yesterday, reaching sizes big enough to produce light rainshowers to the NE of Catalina, and THUNDER just after 6 PM up toward Oracle town! Nice. Looks like a small Cumulus, postcard day today in Catalina. Cloud tops marginal for ice, holding around -10 C, capped by subsiding, dry air. (Except for the light showers this morning between 7 and 9 AM; this note added at 7:32 AM when I saw a shower developing to the west over Oro Valley!) This, from the U of AZ model. Since the air is colder aloft to the N today, ice will likely be seen in some clouds up thataway.
7:26 AM, looking toward Samaniego Ridge. Water still flows down from the upper reaches of Samaniego Ridge from the winter rains. You’ll have to click on the image to really see this water.1:22 PM. Small Cumulus get underway.
2:25 PM. While Cumulus occasionally filled in, they weren’t getting any deeper. No ice visible at this time.4:11 PM. There was plenty of ice around at this time, but most of it, as shown here above and to the left of the right most light standard, ejected out the downstream end of the clouds. This meant that the ice crystals had no chance to grow inside a cloud, but were thrown out into dry air and evaporated. Wider and taller clouds were needed for even decent virga to happen.5:38 PM. Those deeper and wider clouds began to develop. Here a sprinkle or light rain shower reaches the ground toward the town of Oracle. Fifteen minutes later, thunder was even heard coming from this complex.6:45 PM. The thunderstorm that occurred near or over the town of Oracle weakens and recedes. For a time it appeared building Cu overhead of Catalina might produce a sprinkle, but no.6:50 PM. The day ends quietly.
While depressed about a waterless trough approaching us today, well, maybe a few hundredths is all that can fall from its passage, I thought I would depress you that bit more by showing how our smoggy world is connected.
Perhaps you thought, wrongly, of course, that the smoke layer above us yesterday was from from southern California or Mexico. After all, smoke and haze does leak into the SW deserts from the LA area all the time.
But no.
That layer was too high up (estimating above 20,000 feet above sea level); it was in a very noticeable thin, dark layer to the southwest in the morning, then spread over the sky during the day.
Maybe yesterday morning after sunrise you even thought it was “cirrostratus nebulosus”, that vellum ice cloud with little internal structure.
Let us look at the smoky evidence (before any clouds formed):
9:51 AM. Its not Cirrostratus nebulosus. There was no indication of cold clouds over us, as would be the case with Cirrostratus nebulosus.9:51 AM. a thin smoke vellum covers sky. Best seen toward the sun. Looks dark on edge when the sun is shinning on it, like to the southwest yesterday morning.4:21 PM. Still there, ABOVE the Cumulus fractus, though the Cu fra is also impacted by smoke. The faint undulations are above the Cu fra, and show gentle waves, the kind that exist above the “boundary layer” and are not mangled by surface convection and Cu formation.6:46 PM. “Ugh” sunset. Smoky haze layer now really evident. More waviness, betraying its high altitude.6:49 PM, looking SW. Ditto.
Below, a satellite looks at our smog invasion, as indicated by the values of the “Aerosol Optical Depth” (AOD), how muddy-looking it is from up there. Blue is clear, anything else is muddy. Red is incredible. You can see it streaming in from the southwest yesterday morning, 5 AM AST. An annotated version below, in case you’re lost.
Same image, annotated.
Now, let’s see where it came from using the NOAA HYSPLIT model for obtaining backward trajectories for FIVE days, ending at yesterday morning. We saw it streaming in from Mexico, but did it really originate there? Nope.
Backtrajectories for three parcels of air at three levels above us, ending at 5 AM AST yesterday morning. The model thinks that two of the layers above us started way up above 30,000 feet some five days ago, but were lower when they arrived over us. The stuff about 20,000 feet above us (the red line), started lower than those, but was rising as it got to Tucson, that due to passing through the trough that’s approaching us this morning, One would expect to see more layering of smoke today.
And there you have it, “smog across the waters”, the Pacific ones.
Hard to say how it got up there, often its due to forest or other fires in Asia, rather than comes from low level urban smog. It gets here mostly in the springtime because the low pressure systems with their rain belts are weaker, less able to process smog via rain out as smoke layers cross the Pacific, while the jet stream is still quite strong and can carry layers a long ways in a hurry.
Dust plumes from Asian deserts like the Gobi also make it across the Pacific to the US from time to time, again, mostly in the springtime.
—–end of smoke diary module——
Expect shallow to moderately deep, high-based Cu today, ones that will form ice and virga, and of course, it will be windy as well. Seems too dry for much anything to reach the ground here in Catalina below those high bases, a pitiful situation with such a strong trough passing over us today. Check out the U of AZ model for further details. Maybe we’ll see some great lenticulars above the Cu tops…
More possibly illusory water on a hot Arizona desert highway in the 12-14 day range. Massive events are predicted, really; thought you like to see these mid to late April blows, even though they’re likely as phony as a two dollar bill1.
1. Major April rainstorm exits Cal, brings generous rains to AZ. From IPS MeteoStar, these:
Valid (or invalid, probably) for 5 PM AST, April 21st.
2. Second in sequence, shown off Orygon, moves in position for a followup Cal blast.
For April 22nd, 5 PM AST.
3. “Jumbotron 2” marches toward the Cal coast. For mid-April, southern California and Arizona folks would be wondering about “climate change” should this happen, which it probably won’t, but we can dream. Truly, a map like this is really exceptional for the 20th of April due to how strong and deep that low is off ‘Frisco, and the strength of the jet stream at the latitude of Baja below.
For April 23rd, at 5 PM AST. A storm in this configuration, being out of the main jet stream, would take a long time to go by. Might rain for two or three days, so it COULD be a real drought denter. In any event, spaghetti is strongly suggesting “troughiness” in our area over the next couple of weeks, and that will lead to some real rain chances. However, April marks the real beginning of our dry season, averaging only about half an inch here in Catalinaland, compared with over an inch and three quarters in March.
For April 20th, 5 PM AST. Looks very promising for storms during the second decade and beyond in April, as you would know, of course. BTW, we still have some of the Dry Fittm Tees of “I Heart Spaghetti” available for $12 plus $62 shipping.
To help you further understand a perspective on the “gigantism” of the predicted late April storms that came out in yesterday’s 5 PM AST global data crunch, as they are seen in the eyes of meteorologists, let us compare dinosaurs of the Mesozoic as a metaphor:
Valid 65 to 250 million years ago. Humans back then had to be especially careful; death by trampling was quite common.
Speaking of the Mesozoic, I think you would like to hear some birdsongs of the Mesozoic. Its quite good.
About clouds
Been having some fairly nice ones lately. Miscellaneous array from yesterday below:
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1Recall spaghetti has been keeping a trough, i.e., a dip in the winds to lower latitudes, here and in the eastern Pacific for some time; these maps are likely an exaggeration of the REAL troughs that happen in ten days to two weeks, since in these eyes, this series of two storms shown above would likely break April rainfall records in some southern California locations before reaching Arizona with generous rains. So, the more extreme the weather prediction in the 10-15 day period, the more reason to treat it as a knee-slapper. Still, it COULD happen….
Haven’t had much weather/clouds to gab about; maybe I’ll help reader with some extra material today, not usually associated with a site about clouds; kind of go outside the lines a little.
Miscellaneous item 1
The Oracle Road report. Thought you’d like to see that.
Yesterday afternoon’s report. Seem to be some people working. That’s good. You can see some curbing going in, too. Kind of reminds me of how high pressure has been “curbing” our storms lately, to introduce a weather theme. Photo not taken while driving, of course.
Miscellaneous item 2
This. Its quite good. You’ll see people really liking it, too. It may raise the question in your mind, “How many other people are “‘question marks'”? Cloud Maven person?
Clouds?
Well, we had some nice Cirrus yesterday, and for the past few days. Lots more to come, too, but that’s about it for awhile.
3:19 PM. Pretty CIrrus uncinus.3:20 PM. If you on Mt. Everest this would quite a little passing snow shower of tiny crystals, quite fun, because it would only last a minute or so. Well maybe since the wind would be 100 mph, maybe it wouldn’t be THAT fun because the little crystals, likely bullet rosettes, as you would know, would sting your face if it wasn’t protected.
There’ll be a lot of Cirrus over the next two weeks, we hope with some rain underneath, with the best chance being
For yesterday afternoon, 5 PM AST. The green areas represent moist conditions at Cirrus levels, here for about 300 mb or 30,000 feet. Streamers of Cirrus are coming at us for awhile from the sub-tropics. You can see a lot more green in this two week forecast from IPS MeteoStar.
Regime change?
Yep, mostly for Cal, though, as far as rain and snow go. Folks in Cal are quite excited about the drought they’re having, but this April will put a damper on that excitement as the storms roar in from the Pac like they should have all winter. It won’t end the drought, but it won’t be quite as dire, either. You can read about direness here from the LA Times. You’ll read that Governor Brown1 has declared a water emergency in California. Of course, most of the water use is in sometimes inappropriate agricultural practices, like growing rice around Bakersfield in the San Joaquin desert, that kind of thing, not by home owners.
California can be very wet in April. For example, in 1926, and in 1965, Los Angeles got over seven inches, and five inches, respectively. So, “It ain’t over til its over”, the Cal rain season that is, as they say. It will be interest to look back as May arrives, and see how much the drought was alleviated.
How does Cloud Maven know for sure there is a regime change taking place that will help Cal? From a helping of spaghetti. Lets look at spaghetti two weeks out, way more longer than weather models can be considered reliable. Cloud Maven person was VERY excited when he saw this, as you will be as well!
Valid on April 17th, 5 PM AST. Note how the red lines (contour number 576 dm) are squished in the Great SW, drooping southward into Mexico! This is tremendous, since it virtually guarantees a trough in the SW. The other plots are similar. You just don;’t see this much in squished contours very often this far out in the model run in our area. Usually these contours are like the ones off Africa. I hope you know where Africa is…. Those blue lines (number 552 dm contours) are in the heart of the jet stream, really on the poleward side, and notice how some of them dip into the SW. This is good, too. Now, for California, olden studies have shown that its the contour BETWEEN these (564 decameters) that delineates where rain falls when a trough hits the Cal coast. That contour is between the red and blue lines, and so there would be plenty of rain falling in Cal during these first two weeks, with no sign of let up here at the end of the model run. SO, in conlcusion, that’s why CMP is sticking his neck out about a wet, drought-denting April in Cal.
What will our Catalina weather be like in April?
Under this new regime, whether it rains or not, you can expect windier conditions than normal during the month since storms exiting Cal will be close enough to excite not only meteorologists, but a “Tonopah Low” in the lee of the Sierras, something that helps generate wind here as they progress into the Great Basin after forming.
Wow, this is really too much detail for an entire month to come2! Oh, well. Remember our motto here at C-M:
“Right or wrong; you heard it here first!”
The End.
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1Remember how we used to call him, “Governor Moonbeam” when he was governor of Cal the first time around in the 1970s due to his quirky, ascetic lifestyle? That was fun. Lots of quirky people in the Haight-Asbury district then, too. How many question marks were among those folks…and where are they now?
2We’ll be looking back at April come the beginning of May, by which time you will have forgotten anything that was written here, and I could almost anything.
“I think a year ago I sent you the early alert that Eel Ninyo is coming!!! Well, I think I was about 1 year early … the real deal seems to be gearing up for a more major appearance this year … check it out: http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/enso.shtml
“My fingers are crossed for a much more typical event for 2015/16, but then again we seem to be in a very similar place as we were last year at this time (caveat part of e-mail) only a bit warmer in the tropics.”
“We shall see!”
—-from Nate M., NOAA SW Fisheries Center El Niño expert, personal communication, received just yesterday! Excitement abounds!
But, we will see as well…
Below, a different SST anomaly visual from NOAA:
Global sea surface temperature anomalies from NOAA, as of March 30th. The eastern Pacific and eastern equatorial waters are aflame, figuratively speaking, of course. Both the “Classic Niño” (off Peru) and “The New Niño” regions, the latter in the mid and eastern Pacific, have above normal water temperatures!
There is a LOT of warmer than normal water out there! As we know now, the newly discovered “California Niño” helped tropical storms whisk into Arizona late last summer and fall stronger and wetter than they normally would be by providing warmer waters than normal over which they traveled while heading toward AZ. Think of something like the highly-caffeinated “Jolt Cola” in sea surface temperatures for those storms.
Slackening onshore winds along the West Coast last spring and summer created the Cal Niño, something now known to occur from time to time over the decades. And that warm water wasn’t much perturbed by strong storms during the winter, ones that can mix colder water to the surface. The Cal Niño means that IF any storm strikes the West Coast, they would be a little wetter than usual since the air holds more water in it when its warmer.
In the meantime, the much-heralded El Niño of a year ago1 deflated like a New England Patriots game time football into a pile of nothing, wrecking the expectations of frequent late winter and spring rains in the Great SW. Thankfully we had that ONE great, several inches rainstorm at the end of January2 and a couple of vegetation-sustaining rains thereafter.
What does all this mean for our immediate future? Will the late spring be wet? Will we have a great summer rain season?
I don’t know.
But, next winter could be great!
Today’s clouds and weather
Rain is expected to be around today, sprinkles, maybe some thunder due to a weak low aloft passing to the south of us. Cloud drift is supposed to be from the east off the Catalinas, and with the unusual warmth, the day will LOOK like a day in July or August, nice Cumulus building off the mountains in the later morning, reaching the ice-forming level fairly quickly, and then, as you know, out pops the virga and precip. So, it will be a nice photogenic day for you. Check this nice graphic of the expected temperature profiles today from the U of A.
The weather WAY ahead
Recall that today and tomorrow, at one time, as was mentioned here, we were going to experience one of the greatest storms ever observed for this time of year. Well, today’s situation is what’s left of that forecast, a coupla puny showers around, and, sure a trough is here all right, but what a disappointment!
In the meantime, forgetting about the perpetual disappointments for big rains foretold about two weeks in advance, we are once again excited by another great rain here in the far model horizon of just two weeks from now, in mid-April!
Valid at 5 PM AST, April 14th, only 348 h from now! Could put a real dent in our usual April dryness! Colored regions denote those areas where the WRF-GOOFUS model has calculated through VERY sophisticated means, where precipitation has fallen in the prior 12 h! This from global obs taken at 5 PM AST last evening.
Yesterday’s clouds and more
From two days ago. Another comet passed over. Didn’t read anything about it, though. I guess the astronomers have seen enough comets. Probably a little jaded by now by so many of them.Close up. You can see its trailing ice and dust, burned off by the sun. Its great to live in a place where so many comets go over! I think that’s two or three in the past year!Awful green here in Arizona. I wonder how many people know how green it is here? I think a LOT of people have no idea how green it is here (at this time of year).
5:58 PM. Thought for a fun shot I would show you some castellanus from yesterday.6:45 PM. Post sunset, Altocumulus under patches of Altostratus, or, Cirrus spissatus if you like.
The End
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1Not just here, but by people that know more than I do, like the CPC.
2Water is still coming down from the mountains from that 4-6 incher in the Catalina Mountains, water that can be seen still pouring over great boulders in the higher reaches of our mountains producing the morning “glistening rocks” phenomenon. “Glistening Rocks”…. That would be a great title for a love song, a sad one, because as we all know, sooner or later, we won’t see the water producing glistening rocks anymore from the big January rain. So it would have to be about a love that starts out so strong, but then fades over time, finally disappearing altogether.
After a sumptuous day of Cumulus and Cumulonimbus clouds yesterday, a long period mostly devoid of any Cumulus clouds is expected to begin after today.
Cumulus congestus and Cumulonimbus clouds rose early and often to the north of Catalina, but did not launch off of the Catalinas as expected with a minor exception that only the best of the CMJs would have noticed. If you want to see the whole day, devoid of blabber, take a gander at the U of AZ Weather Department time lapse film here. Very summer-looking video yesterday with the Cu moving from the SE as we see on most summer rain season days.
9:30 AM. Heavy Cumulus clouds erupt on the high terrain NNW-NE of Catalina.9:53 AM. Cumulus over the Catalinas are beginning to shoot small turrets up.
10:45 AM. Lookin’ good for a Cb launch at this point, especially with all the Cbs on the N horizon by this time, indicating unusually fertile grounds for a big cloud growth on the Catalinas.
1:58 PM. As Bob Dylan wrote, “You Ain’t Goin’ Nowhere”, you Cumulus clouds. But why? Too dry aloft right here over Catalina, and less so to the north? Probably.
The wait for an explosive development over or near the Catalinas went on and on with nothing happening. In the meantime, Cumulonimbus clouds were getting closer and closer to the north of us.
2:22 PM. As close as they got. Cumulonimbus calvus (“bald”) top about 20 miles N of Catalina protrudes above the lane divider line on Oracle Road.3:25 PM. One pitiful Cumulus congestus cloud rose up to ice-forming levels, glaciated and died. Its head passing almost directly over the house, as you will see. Here, no ice is evident externally, but its in there if you could judge how much higher this cloud was than those that preceded it.3:30 PM. Dissicated by the surrounding dry air, that poor turret dies, leaving visual evidence of the ice inside. Can you see it? Anyone under this would have felt a few drops of rain at this point.3:33 PM. Only three minutes later, death is almost complete, leaving more visual evidence of the ice that had been inside it. The cloud in the foreground obscures the highest part of the turret that shot up so much higher than its nearby brethren. Feeling pretty sad here.3:33 PM. Life-size close up so that you can see what I am trying to describe. The faint veil between the cloud shreds is composed of ice. The shreds are droplet clouds, but also with some ice in them.3:42 PM. The icy top of that lonely turret finally shows.3:42 PM. Close up, just about looking straight up.
3:43 PM. Frame from the U of AZ time lapse camera showing icy top over Catalina. Was it the “Little White Cloud That Cried?”, produced a few raindrops? I think so, since you really have to have ice nearly all the time around these parts to get rain. I’ve spent a LOT of time on this cloud. Maybe its because we won’t see anything like this for so long now.
While the rain at the beginning of April has disappeared altogether in recent model runs (ones after 11 AM AST yesterday), it will likely return in the future. Also, mods now think some rain might occur a week from now.
Litterfolk continue to prefer Bud Light cans and bottles over craft beers. While its interesting to make these surveys, CMP reminds readers, “Litter responsibly; in a receptacle.”
The trash you see here was collected during a single trip to the Sutherland Wash and back.
The Sutherland Wash Flow Report
A little water has resumed flowing in the Sutherland Wash hereabouts due to our recent rain:
The Sutherland Wash yesterday near the Baby Jesus Trail Head. Dog head also included.
The Cottonwoods Blowdown Report
The wind damage below was confined to an area only about 100 yards wide, and at the bottom of a small canyon leading down from Samaniego Ridge. Once suspects that a narrow microburst, some supergust, hit just in here as a rivulet of air collapsed down from the east-northeast after having gone over the mountains. It was likely further funneled by that little canyon and blasted these poor trees.
Note shoe size in lower left of photo.
Yesterday’s clouds report
Cumulus got off to an early start, a line of Cumulonimbus to the north providing a hint of what was to come when the sun came out.
7:06 AM. Cumulonimbus line the northern horizon.7:07 AM. An interesting set of very narrow shadows appeared briefly. The darker one might have been due to a young contrail. They seem too narrow to have been caused by cloud turrets.10:34 AM. Cumulus congestus clouds arose early and often on the Catalinas, becoming Cumulonimbus clouds later in the afternoon.12:07 PM. Some Cumulus congestus clouds sported the rarely seen “pileus” cap, suggesting stronger than usual updrafts pushing moist air above the top upward slightly, just enough to form a sliver of cloud.12:07 PM.12:54 PM. Before long, 47 minutes actually, big complexes of Cumulonimbus capillatus had formed to the north, and distant SW of Catalina.1:47 PM. While pretty, but this expansive Cumulonimbus capillatus incus (has an anvil), pointed to a potential rain-inhibiting problem: perhaps the exuberant convection would lead to an over-anvilated sky? Yes, it became a concern, I’m sure to all of us. Cumulus cloud killing anvilation.3:54 PM. While lightning forked in distant rainshafts, over-anvilation pretty much terminated any chance of rain in Catalina due to Cumulus buildups. The anvil debris clouds are termed, “Altostratus opacus cumulonimbogenitus.” Only clashing winds due to outflows from showers could possibly force rain now.4:43 PM. Clashing shower winds (SW in Catalina, NE towards Oracle) did produce a large final shower in the area. That lower cloud on the left side marks the area above and a little behind outflowing NE winds. Sadly, that wind push from the NE, one that could have launched a big shower here, fizzled out.
The weather ahead and WAY ahead report
More pretty Cumulus clouds today, likely some will reach Cumulonimbus stage (develop ice) and shower here and there. Flow will be off the Cat Mountains and so we here in Catalinaland are a little more elgible for a shower building on those mountains and drifting this way.
WAY ahead?
The models continue to occasionally produce a very heavy rainstorm in southern AZ on or about April Fool’s Day, once again appearing yesterday on the 18 Z (11 AM AST) run. See below, a really pretty astounding prediction again. This system comes from deep in the Tropics, so deep you wonder if it might have some hair from a giant Galapagos tortoise with it. It comes and goes in the models, but there is continuing modest support for a low latitude trough to affect Arizona in the “ensemble” outputs, or “spaghetti” plots.
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1“The Cottonwoods” is a local name given to a portion of the Sutherland Wash next to the Baby Jesus Trail Head. It appears on most trail maps, and is a popular spot for underage drinking parties on weekends.
Precipitation Report for the following time periods ending at: 05:19:00 03/19/15 (data updated every 15 minutes)
Data is preliminary and unedited.
—- indicates missing data
Gauge 24 h total Name Location ID#
Catalina Area 1010 0.20 Golder Ranch Horseshoe Bend Rd in Saddlebrooke 1020 0.20 Oracle Ranger Stati approximately 0.5 mi SW of Oracle 1040 0.24 Dodge Tank Edwin Rd 1.3 mi E of Lago Del Oro Parkway 1050 0.31 Cherry Spring approximately 1.5 mi W of Charouleau Gap 1060 0.20 Pig Spring approximately 1.1 mi NE of Charouleau Gap 1070 ——1 Cargodera Canyon NE corner of Catalina State Park 1080 0.24 CDO @ Rancho Solano Cañada Del Oro Wash NE of Saddlebrooke 1100 0.16 CDO @ Golder Rd Cañada Del Oro Wash at Golder Ranch Rd
Santa Catalina Mountains 1030 0.39 Oracle Ridge Oracle Ridge, approximately 1.5 mi N of Rice Peak 1090 0.43 Mt. Lemmon Mount Lemmon 1110 0.24 CDO @ Coronado Camp Cañada Del Oro Wash 0.3 mi S of Coronado Camp 1130 0.51 Samaniego Peak Samaniego Peak on Samaniego Ridge 1140 0.47 Dan Saddle Dan Saddle on Oracle Ridge 2150 0.59 White Tail Catalina Hwy 0.8 mi W of Palisade Ranger Station 2280 0.63 Green Mountain Green Mountain 2290 0.39 Marshall Gulch Sabino Creek 0.6 mi SSE of Marshall Gulch
More rain is possible, but likely less than yesterday. For the best possible forecast at this hour, check out the U of AZ model.
And why izzat, more precip in mountains?
Let us turn to the cartoons of Rangno 101, summer of 1987, below, where Rangno was forced into teaching a 101 summer class that year in the Dept of Atmos Sci2, University of Washington, when the Ph. D. student that was supposed to do it opted out a the last second, maybe transferred to another team. U of WA accreditation suffered that summer because Rangno did not have the Ph. D., nor even the Masters Degree and yet he was teaching a class. How wrong is that? It can’t be worse than that.
Illustrative diagram of why more in mountains: collection, lack of evaporation. Its kind of what we had yesterday for most of the day. Lower Stratocumulus clouds accumulating on the upwind side of the Catalina Mountains, including Samaniego Ridge, while rain/snow falls from a higher deck. Sometimes this has been called the “seeder-feeder” situation, where the lower cloud is the “feeder.” “Bellevue” should be Catalina, and the “Cascades”, the Catalina Mountains. The main point is that the “feeder” cloud may not precip on its on, but stuff that falls into it gets bigger, increases precip rate.
To emphasize what happens to a drop falling through a collectible cloud, I now show this analog:
An image of precipitation particles arranged by size. Represents what happens when a smaller drop falls into a cloud with droplets above about 20 microns in diameter. They can’t get out of the way fast enough and so are collected by that falling particle. Could be a snowflake or single ice crystal, too, that fell into the droplet cloud.3:30 PM. Lower Stratocumulus builds over Pusch Ridge on a dank afternoon.3:31 PM. Looking at Samaniego Ridge, You can see how the lower clouds are enhanced as the air piles up (gently yesterday) against the mountains.
The incredible weather predicted way out there on the horizon
“Jumbotron” AZ storm showed up again yesterday, in a the second model output. These forecast maps are AMAZING in showing what must be equal to the heaviest rains ever observed in an April in southern AZ. Check this series out (from IPS MeteoStar). I can’t can’t describe how much I love these maps, and I felt, even though the model run is now almost 24 h old (from yesterday’s 12 Z run), that you should see them, too. More importantly, I will ALWAYS have them to look at since they will be overwritten by the next 12 Z run, but they will still be in my blog files. The NOAA “spaghetti” plots has a little support for a trough coming out of the lower latitudes, so we can likely expect something at the beginning of April.
Valid March 31st, 5 PM AST. Possible big rain moves in from the low latitudes.Valid Wednesday, April 1st, 5 AM AST. LOOK at the rain that moves into AZ!Valid Wednesday, at 5 PM AST. Unbelievable for April. Hope it doesn’t turn out that way.Valid at 5 AM AST, April 2nd. The pounding goes on.Valid at 5 PM AST, April 2nd. Two day rains of unprecedented model proportions come to a close.
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1Looked OK when we rode by it a coupla days ago…
2:55 PM, March 15th. The Cargodera Canyon gauge is shown underneath the gigantic writing.
2Widely regarded as the best atmos sci department in the world until that time; you walked the halls with giants in those days.
Kind of a dull day yesterday. Not much to look at. Some Altocumulus with an interesting, slotted wave pattern to start was about the only interesting thing in the morning.
Then some small Cumulus that continued to agglomerate into masses of dark Stratocumulus, with a little rain to the north of us. You probably didn’t see it. The darkness of the clouds was likely due to higher than normal droplet concentrations, which in clouds, causes the bottoms to be darker because the smaller droplets associated with high droplet concentrations causes more sunlight to be reflected off the top of clouds. But you knew that.
You probably also know that the brief, and weak shafts of rain to the north of us in the afternoon meant that cloud tops were barely reaching the ice-forming level, certainly were mounding ones, analogous to the rolling hills of Ireland rather than ones protruding upward very much like Kilimanjaro or something like that.
Sunset was OK, not great.
A stupendous storm showed up in the fantasy part of the model run, out two weeks, or on April 1st. That’s a little late for a stupendous storm, but it was fun seeing the computer maps of one.
Today, and not just because I am lazy and have to go right now to feed some horses, I thought I would just insert all these images in whatever way WordPress decided they should go and let you puzzle them out, e.g., name clouds, figure out what time was the photo taken, or, just look at them as a review of your cloud day.
Btw, whilst out on dog walk yesterday, saw that in the Cottonwoods area by the Baby Jesus Trailhead, several 6-9 inch diameter cottonwood tree branches were blown down during Sunday’s windstorm, one younger tree had been topped. Looked like a very small, supergust burst had done it, maybe less than 50 yards in diameter.
I figure today’s weather is pretty well presented by the NWS, and your favorite weathercaster, so why duplicate good efforts?
10:47 AM. Altocumulus perlucidus undulatus translucidus (has waves in it; is thin).
The End, of one of the easiest blogs yet! Maybe will practice more WordPress chaos in the future!
Sample frame from a video running when the peak gust hit, estimated at over 60 mph by “yours truly”, if that is, in fact, the case. Some roofing material blew off, too.
Equestrian Trail Road spewing dust, estimated peak puff gust, in this King of the Gusts, 60-70 mph. Only lasted a few seconds. Not mashed plants due to winds.
Cloud Maven Person was doing other things, not thinking about weather, when he finally began to notice that the winds in “The Heights” were approaching 100 mph1; great clouds of dust suddenly rose up from our dirt streets; dogs blowing ahead of him on his dog walk when going westbound on a dog walk, sandy grit sanding off the hair on the back of his legs. You get the picture.
Well, it was caused by an unusual situation of wind coming OVER the Catalina Mountains, which usually block east winds from us quite well, while the city of TUS gets ripped.
Too, yesterday might have been like that situation some of you remember that affected California’s San Joaquin Valley in December 1977. Winds, forced OVER the Sierra Nevadas, then collapsed down on poor Bakersfield and vicinity, the air accelerating as it fell down the Sierra mountainsides going faster and faster, driven by a HUGE high pressure inland over Nevada, and lower pressures offshore, peaked at 130 mph!
Something similar to that situation may have been what happened yesterday here in Sutherland Heights. Both Froude and Richardson Numbers, to throw in some high sounding terms that characterize flow, along with the strength of the winds piling up against the Catalinas on the east side, were just right so that the air went OVER the Catalinas instead of around them. End of potential explanation.
Below is yesterday’s TUS U of AZ launched sounding from IPS MeteoStar, which still isn’t charging anything to look at their stuff even though they said they would:
The TUS balloon sounding for 5 AM AST yesterday morning as the winds were picking up. The arrows are point to stable layers where the air, as the winds piled it up against the Catalinas, were resisting being lifted, and under less forceful winds, likely would have gone around the Catalinas instead of over. But those two layers being raised up by the wind, the air more impetus to go down the west side of the Catalinas after it was forced over the top. Those wind barbs of the right indicate that the winds were banging against the Catalinas as 40-50 mph near the top of Mt. Lemmon, and 50-60 mph not much higher above the top.
Corroborative data: on 2 h dog walk just after sunrise, taking them on the ridge on the east side of the Sutherland Wash2 , the wind on the ridge was coming right at us from Ms. Mt. Lemmon, of all places! Very unusual. Closer to The Heights, the wind turned more more from the northeast.
Oddly, just down on Swan below us, the wind were not unusual at all, only 20-30 mph, one experienced observer reported. That kind of microscale thing happens in these situations, when the air finds channels in canyons and gulleys, so “oddly” really doesn’t apply, and I don’t know why I said it.
Well, that’s what I think happened; air accelerated downhill after being pushed over the top of the Catalinas, and gave us extra strong gusts.
Did you notice that during the winds, it could almost be calm, but you could hear another gust approaching like the roar of a gushing river out there in the desert? That was cool.
The weather ahead.
Mods continue to indicate a showery SE Arizona for a few days beginning tomorrow in the extreme SE as weak troughs in the southern band of the jet “influx” some mid-level and higher moist layers to begin with. Water vapor already increasing over us, so maybe we’ll see an Altocumulus cloud later today.
Aerosol forecast: Look for enhanced smog with this air mass coming from the south and southeast. Dang.
The End.
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1If you round up from 60 or 70 mph in those momentary, less than 1 or 2 second blasts.
2Which still had water in it in some parts, but not at the Cottonwoods anymore.
The Sutherland Wash at the Rusty Gate horse crossing yesterday morning. The water disappeared here, too.The Rusty Gate.
