The late afternoon yesterday was like a Carpenter’s song, i.e., “easy listening” interrupted by Metallica, Megadeath, Slayer, Black Flag, Helloween, The English Dogs (“She Kicked Me in the Head and Left Me for Dead”), etc.
A day filled with moderately promising Cumulus congestus and brief area Cumulonimbus clouds, was suddenly overrun by a black steam roller with a watering tank behind it, and also having a big fan, to wind up a semi-ludicrous metaphor, coming down out of the northeast bringing an early nightfall, blinding rains, and winds of 60-70 mph. It was an astonishing change, and if you weren’t watching, but rather watching TEEVEE: “Ka-blam! What the Hell?” (More on TEEVEE later; see last caption.)
Some rain totals, ones up to 2.64 inches (!) can be found here in the listing of Pima County ALERT gages. More results will be available during the morning from the U of AZ network here, and from the CoCoRahs network. BTW, if you haven’t joined up, it would be good if you joined up with both of these latter “rain gangs.”
Of course, neurotic-compulsive cloud-maven person was watching for you. I only wish I had a huge microphone yesterday evening so that I could have alerted the people of Catalina, “CDP”, to its impending weather doom.
Non-weather side note: “Catalina: its not a town”, but rather, a “Census Designated Place” (CDP) where people are clustered, according to the Census Feds. Namely, we’re Catalina, CDP, Arizona, 85739. Its quite amazing the kinds of things you might read here, and its usually right after I find them out myself.
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Enough collateral information.
The day, had a tranquil but portentful beginning filled with potentiation, with those low, warm cloud bases. However, with the rising temperatures, ones into the mid-90s, so, too, did cloud bases rise. This is normal. As the daytime relative humidity falls, the cloud bases form at higher and higher levels. I hope you didn’t get upset seeing that the afternoon bases were above the top of Ms. Lemmon. Still, those higher, cooler bases did mean that the rain had farther to fall through dry air, not as good as having them down on the Sam Ridge line.
10:23 AM. Turrets begin shooting upward from bases topping Samaniego Ridge. This is good.1:37 PM. Weak Cumulonimbus (Cb) finally forms in the area. Getting a little concerned at the lack of “progress”, and much higher bases now.1:56 PM. Another weak Cb forms over the Tortolita Mountains.
3:43 PM. Another weak Cb forms this side of the Tortolita Mountains. That promising dark base above Catalina unleashed a sprinkle! (Sarcastically spoken).3:18 PM. Finally, something close! Looks promising, but fizzled out.4:14 PM. Not looking good. The Catalinas are back to producing shoots, not Cbs.
5:25 PM. Then “The Man” showed up, a gigantic Cb, one like the model had been suggesting would occur in the prior evening’s run.6:28 PM. The “black steamroller” appears, about to blow over lawn furniture everywhere.6:56 PM. Rolling into Sutherland Heights above Catalina, CDP, this 30-minute “incher”. I wonder who was watching TEEVEE, perhaps planning a TEEVEE party tonight, and not watching?
For a great movie of yesterday’s clouds from the U of AZ, go here.
Oddity
An as yet inexplicable odditity to yesterday’s stupendous storm. The lack of cloud to ground strokes; I didn’t see ONE, and I was looking. Second, the frequency of lightning was as high as it gets. In the dusky light, a new flash within the Cb in less than ONE second at the peak. Its was remarkable. That same kind of activity could be seen last night as the storms receded from us with almost continuous in cloud lightning, but no strokes to the ground (at least during the time I watched.
Today?
Still humid, still unstable aloft. Mods say another active day, so watch it (not teevee)!
While “only” 0.42 inches fell here (a great rain, really), and 0.43 inches at the ALERT gage on the CDO bridge at Lago Del Oro, Sutherland Heights got whooped with a whopping 1.75 inches yesterday afternoon in a remarkably dense and windy rainshaft. But I am getting ahead of myself with this report and this sunset photo. First some more precip reports, here (ALERT gages) and here (U of AZ network). “And the winner is…” (as of 9:18 AM) for the greatest 24 h amount in ALL of Arizona, Bonita Canyon near the Chiricahua NM (2.06 inches) followed by Sutherland Heights!
Check the rainlog amounts above and here for CoCoRahs!
On to our story of the day, to be interrupted later by another learning module…
The day started like any other one, with our often observed morning Altocumulus perlucidus translucidus deck covering most of the sky. With the rising sun, Cumulus began to appear and grow rapidly with bases of those clouds topping the Samaniego Ridge line, something that is a rare occurrence. By 10 AM, showers were already appearing on the Cat mountains; those towering Cumulus clouds had already reached the precip forming level.
By 10 AM, you should have been VERY excited, talking to the neighbors about the low and warm cloud bases; alerting them to possible exceptional rains.
6:49 AM.9:29 AM.10:11 AM. Little acorns are turning into giant sequoias already!
At this point, I feel I have to insert a diversionary learning module. If you’re one of those people who doesn’t care about what’s going on “way down inside” these Cumulus clouds, as Robert Plant might put it if he was a nephologist instead of with Led Zepelin, then skip this module.
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Begin learning module.
With cloud bases as warm as 15 degrees C (close to 60 F!) almost certainly the first precip to form in yesterday’s clouds were drizzle drops (remember, to keep Cloud-Maven from getting mad at you, having “rain rage”, you have to remember that drizzle drops are between about 100 and 500 microns in diameter and that at that size, a few human hairs in diameter, they almost float in the air; umbrellas can be useless when it is drizzling.
Dirzzle is NOT a sprinkle of larger drops, dammitall, and its important to me that you know that!
Here’s the interesting part (he sez). Before drizzle and raindrops can form in a cloud without ice being involved, the droplets inside the clouds must reach 30-40 microns in diameter, maybe a third of a human hair in diameter.
Until they reach that size in the clouds, they will bounce off each other like itty bitty marbles or ping pong balls. After that “magical” size greater than 30 microns, they can coalesce, merge into one larger drop, which then falls faster, collects more drops, and, if the cloud is deep enough, fall out as a raindrop.
In the olden days, this was called a chain reaction process by cloud seeding nut and Nobel Laureate in chemistry, Irving Langmuir, who published a nice paper on this in 1948. Today most folks call it the “warm rain” process, because ice is not involved. Happens a LOT in the tropics, and places like Hawaii, but its rare here because our cloud bases are so warm as they were yesterday, and our clouds, being “continental”, that is, having high droplet concentrations (hundreds of thousands per liter of air) makes it hard for cloud droplets to grow up to be 30 microns in diameter. BTW, raindrops as big as 1 cm in diameter, the biggest known size, came out of a cloud in Hawaii that had no ice in it.
So, for me, a cloud-maven, it was quite interesting yesterday to see that our cloud bases yesterday were “Floridian”, and likely had a good deal of “warm rain” in them, even before they towered up to 50,000 feet, -60 C, and had a ton of ice in them. Its often the case that those raindrops are carried up to levels where they freeze and jump start the ice/hail forming process higher in the cloud via splintering (banging into drops and leaving fine ice shards in their wake) and shattering (they break up upon freezing).
End of learning module; you can wake up now…
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The payoff by those low, warm cloud bases? Exceptional looking clouds, a travelogue in the sky really, more like ones you’d see in Florida in the summertime, Bangladesh, Phillipines, Jakarta, etc. Here they are, before and during the Big Dump on the Sutherland.
12:49 PM. After a huge storm over the Torts, an ominous line of Cumulus clouds began extruding westward toward Catalina.1:07 PM. This is looking VERY good, but, with all the cool air, can these Cumulus bases really be hiding tall clouds? You never know until you see the streamers. Excitement level probably should have been around a 6-8 of 10 here, holding back that bit so that you’re heart is not broken by a later broken up cloud base.1:29 PM. “Thar she blow”s, though actually, its like an upside down spouting whale; the streamers begin to emerge in the distance.
1:28 PM. Just six minutes later!1:31 PM THREE minutes later. Excitement level 9 of 10.1:36 PM. Full blowed tropical Cumulonimbus shaft. Thinking about that “Rawhide” theme seeing this, after all, this is “Arizony”: Rollin’ rollin’, rollin’, though the streams are swollen, keep them dogies movin’, rawhide” rain and wind and weather, hell bent for leather….’
That last shot is of the one that rolled into the north Catalina area and Sutherland Heights, dropping 1-2 inches.
Tried to beat it up to Sutherland Heights but was late, visibility
was bad, lightning close by, so stayed in car with one of our (wet) dogs, Pepper.
As a result, in no “in the storm” shots. Sorry.
Oops, today?
Latest mod run from 11 PM AST last night by U of AZ here. Surprisingly, this model run thinks today is quite a down day, not much shower action here. Must be due to the cloud cover keeping the temperatures down all day (in the model) Or something else that is not immediately apparent to me, anyway?
But, temperature is NOT everything, as we saw yesterday. When the air is this humid, and deeply humid as yesterday, it doesn’t take blazing temperatures to launch Cumulonimbus clouds.
So, it seems likely, with the usual daytime thinning of these clouds, perhaps not enough of that in the model, that tropical Cumulonimbus clouds will once again arise here and there. I think Bob, our local scientist expert in these matters, will fill in some of my blanks on this later. He’s probably not up yet.
Only a marked change in the flow pattern at near the top of our Cumulonimbus clouds can really do much, and its not obvious any thing much is changing up there (is it helping air to rise, or to descend and dry out?) The latter can put a real damper on cloud development even if there is initial good humidity, and right now, it doesn’t get any wetter in AZ than it is right now, this morning!
What an amazing, Biblical sight1 that came across the Catalina Mountains yesterday evening, that shaft of intense rain and attendant rainbow! After a day where it looked like rain might not happen here, those earlier Cumulus clouds being pretty lazy really, this behemoth powered across Tucson and the Catalina Mountains dropping 0.56 inches in momentarily blinding rain blown on 60-70 mph gusts, with numerous cloud-to-ground lightning strikes, taking down power lines, and causing a 6 h plus power outage in Catalina. 0.51 inches fell here in 10 minutes!
Oops, forgot to remind you: Don’t forget to go to the movies. Shows the backside of what hit us just as the day ends.
How great this rain will be, too, for our stressed desert-thornscrub vegetation after almost a week of dry conditions. (Only 0.17 inches at Sutherland Heights, though.)
For me, yesterday evening produced the most dramatic sights I’ve seen here in four years in Catalina. I hope you caught it, but if you didn’t, here are a few of the most dramatic ones. The first, penultimate shot was from the front porch about three minutes before bedlam hit Sutherland Heights. Below this, those shots leading up to it.
7:04 PM. The Arc! Woulda been outside, gotten a better shot, but just there was a cloud-to-ground strike about 100 yards away a little before this “whilst” I was being a dummy outside grabbing the shots below.6:34 PM. Storm hitting Tucson. TEEVEE weather presenters very excited. Its heading this way, but will it survive passage over the Catalinas? A successful passage will require the renewal by new rising turrets.6:50 PM. Looks like it will make it over the Catalinas. Note cloud base AHEAD of the rain shafts. This is looking pretty darn spectacular with the sun going down.6:54 PM. 100 photos later, “executive override brain function” for controlling impulsive actions failing. Taking too many photos; agog at what I am seeing. New cloud base holding up.6:58 PM. “Whoa, Nelly”, as Keith Jackson might say. An astounding sight; doesn’t look real. But note clearing just behind shaft. So its not a wide storm at all. Maybe it will miss us, as they have done lately. The “Arc” is just developing at left of the shaft. More importantly, the base now overhead has held up and promises a new dump will emerge. Each of these shafts only lasts a few minutes, and so you have new ones if you are going to get ROYALLY shafted (to use terminology appropriate for Olympics now in progress in Her Royal Majesty’s Britain).
A repeat of yesterday today? Not bloody likely.
Oh, well, any rain will be great, but drier air is moving in. Check it out here from the University of Washington Huskies’ (some former of whom, if that is correct english which I doubt, are in the Olympics, for example, women’s volleyball, but not in beach volleyball which I seem to be watching a lot of) Weather Department here.
Note the drier air moving in from New Mexico and west Texas in this loop. Just the same, it can still rain here some because while drier, it’s not dessicated air and so the usual isolated Cb should be around. So, keep watching, keep cameras ready and charged.
The End.
————————————————————————————————————————————————————-1Biblical allusion is to the “ARK of the Covenant” whose activity was demonstrated in a movie with Harrison Ford some years.
Of course, alluding today in the title to the great western movie with John Wayne…
Every which way you looked yesterday afternoon, there was a great rainshaft. 1.85 inches fell in one hour at Picture Rocks Community Center yesterday afternoon, 2.01 inches total. Several stations around the county had another 1-2 inches yesterday. You can see the Pima County rain lineup here. Seems the great amount in the Catalinas was about half an inch in a gage at Samaniego Peak. Probably twice that between gages up there in the hot spots, where the best columns of rain fell. Also, it would be good to examine our U of A rainfall network today, too, for some jumbo totals. Values are being added during the morning hours as a rule.
Catalina? Well, a measly 0.05 inches fell here after 7 AM until this morning from side-swiping Cumulonimbus clouds, though Sutherland Heights did receive a more respectable 0.28 inches–just measured it. . So, if you were outside yesterday, you saw heavy shafts of rain all around, but none developed over us (the best kind), or moved in here.
But, then, 1.85 inches in an hour, probably most in a shorter time than that, might be “counter-productive”; might make Catalina into a news story, and not a good one… So, I’d better watch what I wish for.
Here are some views of yesterday’s “clouds and columns” of rain yesterday. And, as has been the case, the day started with heavy layer clouds, Stratocumulus and Altocumulus, and a nice, but very brief sunrise “bloom” shown below:
Once these clouds thinned by late morning, Cumulus began to surge upward over the Catalina’s, and reflected an usually strong east-southeast wind just above mountain top levels by trailing over Catalina from Mt. Lemmón. These reached the ice-forming level (read, began to produce rain at the ground) in a series of showers and thunderstorms by 11:30 AM (2nd photo).
Looked, too, like another tube (funnel cloud) at 3:48 PM yesterday off in the direction of Marana, but I’ve posted so many of late I thought I would just post it at the bottom of these more interesting photos.
11:03 AM. Cloud “street” off the Catalinas.11:31 AM. From Mt. Lemmon to us, straight overhead!1:01 PM. Repeated showers STILL trailing off the Catalinas! But not over us.
1:01 PM. First major-colossal dump occurring N of Park Links Road. Note bit of rain falling from overhang cloud from the prior photo. Tops shearing off; rain-producing part (top of photo) has no underlying cloud for the drops to grow in as they fall, so no collosal-major dump. Did start thundering about then, though
1:16 PM. This is so pretty! Now, one of those turrets has leaped upward, more or less straight above the bottom of the cloud, and now, though a small one, a major-colossal dump on the Cats. I love these scenes here!
2:36 PM. Its gonna miss Catalinans, BUT, this is where you want to be under. Look at that downspout! That whole cloud is loaded with precip, and the Big Boys are dropping out now, and just before this, the largest ones able to overcome the updraft so its especially great and exciting to be under a cloud like this just as those strands of rain/hail drop out. Also about the time such clouds get “plugged in” and send light daggers to the ground, as in this case.
2:41 PM. Its just FIVE minutes later! You probably haven’t even gotten in your car yet to try to get over there. Its too late. This was a one dumper and gone. Faded away into just a residual ice cloud.
2:57 PM. Done, cooked, fried. Without the flanking clouds piling up into new turrets that reach the ice-forming level, all you have after just 20 min or so, is this sad sight of a dying, once proud Cumulonimbus cloud. Rain here likely due to aggregates of ice crystals called snowflakes if you up there flying in them.
3:04 PM. What was truly remarkable about yesterday was that those smallish Cumulonimbus clouds just kept on generating over and over again off the Catalinas. Very unusual, and was a measure of how unstable, how easy it was, for the clouds to surge upward yesterday.
3:47 PM. Another one! Unbelievable. Like the bunny, going and going and going.4:01 PM. Its practically nighttime, cool, overcast, not good for Cumulus, and yet look how this little group was trying so hard to be a rain cloud. Sadly, they didn’t make it. Have never seen such tall thin clouds like this here in this kind of environment, that’s why I posted it.3:38 PM. Likely funnel cloud just above bright spot, the longer filament, not the nub from the cloud base in the foreground, but from the next base farther away.
Moisture continues to revolve into Arizona from the southeast and so it would appear a similar day is in store for us. Oh, goody.
“Shafts to the left of me, shafts to the right of me, but here I am, stuck in the middle with you.” (Yeah, and without any rain.) Who can’t forget Stealers Wheel? Most everybody I guess.
Here is an example of a “middle”, an empty region between rainshafts in this case. You don’t want to be there. Boring, as in “baby I’m bored”, for emphasis. But that’s what we “Catalonians” got yesterday, the middle.
1:51 PM
As the three of you who follow this blog know, I don’t usually concentrate photographing the “middle” or “tweeners” as some baseball-cloudcentric fans might call these kinds of scenes; I like to show the shaft. I NEVER get tired of shafts, or, in fact, being “shafted” by rainshafts.
Never will.
I did think, in taking this first shot, that the dark base ahead of the “middle” would drop its load on me. I had already prepared a story in my mind with a “happy” flash flood ending. I readied my camera, got the tripod out.
But, no. It missed me and my gage, slipping off to the right, or to west from the spot above, dumping its load on north Oro Valley and Saddlebrooke. I can’t wait to see how much rain the rainloggers over there report this morning compared to my crummy 0.03 inches. Oh, well. There was generally about 0.4 to an inch in the Catalinas. Hooray! More green, more water!
Commercial break:
In trying to make the best of a situation that was fast becoming a disappointment, I noticed some birds floating around in the updraft of the dark base as it came almost overhead. Suddenly, I realized, as I started to carry out my niche of photographing cloud bottoms, that a cloud bottom photo with some kind of bird in it, who knows what, probably using the updraft into this cloud base to ride on, a kind of “bird surfing” would likely appeal to the “bird set”, Audubonners and the like, etc., thus expanding my commercial base beyond just the cloud bottom crowd. It was a quite a striking, moneyful thought.
BTW, these birds are doing what cloud seeding aircraft do, circle in the updraft below cloud bases and release nuclei, sometimes “hygroscopic” nuclei, ones that form drops, and sometimes “ice nuclei”, ones that form ice crystals. See, at last I got some education in! You got schooled! Didn’t see that one coming did you?
I’ll address whether cloud seeding works in a rant some day…
Below, the resulting symbiotic photo, now named, “Base and Birds, or the more accessible, “Surfing Birds.” It will cost you one dollar to download it….hahahah, sort of. “Hey”, let us not forget the words of the great Danny Elfman, Oingo Boingo: “There’s nothing wrong with capitalism…don’t try to make me feel guilty…”)
—-end of commercial break
1:51 PM. Birds, surfing air, below cloud base.
BTW, the discerning cloud bottomer will notice that this base has some inconsistencies, is not quite solid, suggesting its not due to a large continuous updraft area; only part of it is. This was a clue that there could be a disappointment.
Kansas skies?Oh yeah, there were some itty bitty tubes on the front side of that jack hammer of a storm that rolled into Oro Valley from Tucson yesterday around 1:50 PM. Take a look below. Second time in a week have seen a “tube”. Getting very tubular around here. Check out the U of A time lapse movie for a real fright night day as that big boy goes by. “Totally awesome!”
Some nice lightning around, too. Here are a couple of those shots to end things off with.
1:49 PM. Tubes?
Finally, a nice sunset peering through a hole in an Altostratus cumulonimbogenitus opacus overcast that ended our day–english translation, thick debris clouds leftover from our many thunderstorms yesterday.
2:04 PM. Should probably go inside now…
Today?
Another day, another dollop? Photogenic Cumulonimbus clouds all around again this afternoon. Let’s hope its more than a dollop today.
More details here from the U of A and here from our friendly NWS, always there when you need them and when you don’t.
OK, this one’s a little long, lots of twists and turns in the weather plot before its over….but as the Arthur, I felt they were needed (that is so funny! 🙁
We’ll start with the “end” of the book; cut to the chase: the mods have another possible big day this afternoon, Check it out here.
The result of heavy rain in the Catalina Mountains late yesterday afternoon is shown below. These shots were about 2 h after the main dumps up there had occurred. Some neighbors and me was just standing around chatting, had come down to see if there was ANY flow in the CDO. Nope. But, since we were having a good time, kept on chatting. Then, the roar! (BTW, you could hear the Sutherland Wash roaring from about a mile away. Must’ve been something over there.)
7:16 PM. Sittin’ around chattin’ up neighbors and vice versa. Nothing seems to be happening in the dry CDO wash at E Wilds Road.7:28.00 PM. Oops.7:28 PM plus 3 tenths of a second
Amounts around here in and near Catalina were generally between 0.4 and 2 inches, with the lower amounts here and up at Sutherland Heights, darn. You can see the Pima County rain table (here) and the U of AZ rain network totals here (they’re usually not complete until later in the morning). These are totals for the 24 h ending at 7 AM. You can also review yesterday’s cloud action in the U of AZ time lapse movie for yesterday, rated R for violence. Max totals in NW Tucson were over THREE inches!
Below is a review of yesterday, beginning with an attempt at some true art, one I’ve entitled for a possible museum showing, “Ants and Castellanus.” Remember, Altocumulus castellanus/floccus are a good indicator of an “unstable” atmosphere at the level they formed at. The ants, flying ones, tell you that there was good soil moisture, which is actually important in keeping the boundary layer air moist by replenishing it during a warm day. It was good seeing those ants in swarms like that, they seem to be having a lot of fun, exuberated by moisture, perhaps thinking of more soil moisture ahead.
So, in this ONE photo I took for you, you have TWO indicators that are suggestive of the day ahead; it might rain again1. You could tell your friends things like this and sound quite wise concerning nature. Really something like this should be in the Farmer’s Almanac.
Frankly, while the best models we have available had quite the rain over us yesterday afternoon by 4 PM, it didn’t shape that way. It was still dry and not much going on. I am guessing that the colossal amount of rain-cooled air from the previous rain day kept the trigger point (the high temperature) for huge clouds a bit delayed, but it was only by about 1-2 hours! The rain arrived here between 5:30 and 6 PM. Pretty remarkable accuracy, never mind the bugs, when you think about it.
Often on days like this, where the atmosphere is primed for huge clouds, they go through cycles where it seems like all of sudden they putting themselves together, bases clustering for an upward explosion, but then a few minutes later, the whole sky looks in disarray, the bases having broken into small segments, tops of the clouds ragged. That happened a couple of times yesterday afternoon and so I wondered if the explosions would ever happen. Sometimes, in time lapse films you can get a sense of this as waves, gravity waves like ocean ones, in the atmosphere pass by with the clouds in films seeming to all fatten up at once, and then subside as the wave passes.
But then, it happened, all of a sudden, first an cloud on the west end of Tucson, south of us, which had been struggling, began massing, “shafting” (putting out multiple rainshafts), and putting out lighting. That was it, with the model background of massive clouds, you knew that this was it, the sky was going to go bonkers all over. With but a brief interruption, it did. I was beside myself snapping photos every few seconds, being out of control again with these stupendous scenes of transition and drama!
Here are too many:
2:49 PM. Its supposed to be raining all around, but nothing is happening. Clouds are ragged and “ill-formed.”3:09 PM. OK, lookin’ good, base massing over Cat Mountains.3:09 PM. Phooey, falling apart, stagnating.4:09 PM. Ok, at last; this is looking good, VERY good.4:23 PM. Bigger and better, now “shafting” (producing rainshafts).4:30 PM. Phooey, fizzling out.4:34 PM. When did this happen? This looks tremendous. Must be that SW wind pushing out of the dying showers to S-SW and lifting the air over the Catalinas.4:39 PM. Here come the strands, the ones that lead the dump! I might get something, its gonna be close.4:42 PM. “Thar she blows!” But I will be missed.
5:17 PM. When did this happen#2? This is an incredible sight; an outflow from some GIGANTIC complex roaring past and over Pusch Ridge toward Marana.5:21 PM. Only four minutes later but look how far its pushed out from Tucson!5:30 PM. Outflow winds and arcus clouds push into Oro Valley.5:35 PM. In the meantime, the dump on the west side of the Catalinas, shown here, is beginning to push air back toward Oro Valley leading to clashing winds to invigorate clouds not yet raining upwind of Catalina.5:39 PM. Outflow winds from the Catalinas produce this diabolical sky. About this time, and for another half hour, lightning in the clouds overhead and toward Charoleau Gap occurred every 1-2 seconds! Yeow.
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1I would consult some computer models before taking that thought too much farther. For example, if the computer models are showing rain later in the day, and you’ve seen some castellanus and flying ants, I would definitely mention this proverb to friends, say, during a morning walk. Otherwise, keep it in your back pocket.
With dewpoints hovering near, and even eeking into the low 70s in AZ, with giant thunderstorms complexing our weather with sudden stupifying downpours, one wonders, after all of these blogs, this “body of work” if you will, if the several people who comprise the Cloud-Maven blogpire, one that radiates from one part of Catalina to another, would be able to know where they were if they could be transported to the locations in these two sets of four photos. (BTW, all of which were taken by the present Arthur–hahahaha.)
OK, drum roll, insert photos here.
Two were taken at the Madras (now Chennai) International AP in Meenambakkam, Tamil Nadu, India, in September 1975, and the other two just yesterday afternoon in Catalina, where most of us live. Remember, there are mountains in India, so just because you see some mountains doesn’t mean its NOT India. Also, just because I mentioned two were taken in India first, doesn’t mean necessarily that they are the first two shots below.
OK, begin thinking and analyzing, maybe drink some more coffee.
OK, if you guessed the first two photos were actually taken in India during the REAL monsoon in 1975, you were right. That’s a friend, Venkateswaran, on the far right of the first photo admiring the arcus cloud ahead of the downpour.
The result of our “pseudo-monsoon”, which was a pretty good imitation of the real thing yestserday, shown in the second set of two photos, was another 1-2 inches in the CDO watershed, 0.75 inches in here SE Catalina, 1.16 inches at Sutherland Heights, and a whopping 1.92 inches yesterday afternoon and Our Garden (Jesse, personal communication), keepers of the Catalina long term climo records.
What was the effect on the CDO River at the bottom of East WIlds Road?
It got huge. Coulda rafted brown water. Below are more shots of the CDO wash/river again for the second day in a row, ones after yesterday’s dump. A young bystander (i.e., fellow gawker) said I had arrived after the peak! Said the churning waves that developed every 20 min or so due to surges down the wash, were 8-10 feet high! Here they were about half that, 4 feet or so from trough to ridge. I wanted to “shop” a water buffalo in one of these photos so BAD!
Of course, this flood is “mild” compared to the Aug 25th, 2003 flow, which covered Lago del Oro road.
BTW, rainfall totals hereabouts are now up to or exceed the average July monthly amount of 3.xx inches.
The Weather Ahead
With high dewpoints once again today, 64 F here in Catalina, more large thunderstorms are pretty much in the bag, and importantly, this assertion is corroborated by calculating models, all that I looked at. Here is the forecast rain picture for 4 PM today from the Beowulf Cluster at the University of AZ: 4 PM 20120715_WRF Precip (Flash Animation) As you will see, WIDESPREAD rain is expected, with totals in the “best” cores getting up to 1-2 inches again. Wow, three days in a row of major storms.
Things are supposed to dry out some tomorrow, but showers will still be around before a break of a couple or three days.
Rain shafted, that is. 0.50 inches in 15 minutes yesterday between 2:43 and 2:58 PM. 0.76 inches in 13 minutes in the Sutherland Heights district above Catalina, with wind gusts to 50 mph! One of the most memorable summer days ever here in Catalina. One station, Oracle RIdge in the Catalinas, 1.5 miles N of Rice Peak, reported 2.32 inches. No wonder we had a strong flow in the CDO wash yesterday afternoon! Rafting anyone?
And what a spectacular beginning to the day, filled with portent by those ultra low Stratocumulus and Cumulus cloud bases hugging Samaniego Ridge, the humid air that enveloped us reminding one of the Phillipines, or Gainesville, FL, in July. That was a real key to the kind of day that likely lay ahead, those low cloud bases telling us that our humidity was not just in a shallow layer near the ground as we could feel.
But who needs Florida in July when you can be right here in Arizona? Voluptuous Cumulus congestus clouds piled into the heavens early and often just like in FL, some with pileus veils as well, also common in FL, in route to blossoming into Cumulonimbus calvus, then capillatus clouds, tops reaching above 40,000 feet above us. The Charoleau Gap/Oracle area were hit often all morning and into the early afternoon with great rolls of thunder with one station reporting more than two inches (as noted) and several over an inch.
Because there was so much water in the air, unusually dense rainshafts poured forth from the bottoms of those clouds in just a couple of minutes, oblitering the scenes behind them. Too much precip up there for any updraft to hold off for very long, then the collapse!
Here’s one sequence, the one that led to our 15 minute drenching. The first shot shows the blockbuster that roared down through Charoleau Gap. The ferocious NE winds that preceded the rain caused the clouds to its south (where I was) to experience a growth spurt by displacing the humid air near the ground, jacking it upward. I noticed this happening by the second shot. When the winds hit, you always start looking up for “surprise” developments right over you. But after that, trying to catch a daylight lightning flash from the Charleau Gap storm, forgot to check that darkening base every 12 seconds as I would normally do. My apologies, since the third shot showing the fully collapsed, unbelievably dense rainshaft (3rd shot) was a FULL EIGHT MINUTES later. Damn.
Finally, the last two are during the height of the storm itself. Phenomenal intensity.
I suppose I took too many photos, only about 0.0004% of them can be shown here, but, let us not forget those PRO photographers that had ONE day to document, was it the Chiracaua National Park a couple of years ago? One said he had been conservative and “only” took 2,000 photos, while his friend, more promiscuous, took 8,000 that day! I only took 200 or so…
Here’s a gallery of yesterday’s scenes, including suggestions of a funnel cloud a few miles NNW of Catalina at 10:45 AM. BTW, you can reprise the whole day, as through you were a student standing on top of Atmospheric Sciences Building at the U of A here.
11:07 AM. Cumulus congestus trailing NWward from the Catalinas shows signs of glaciating, producing a shaft.11:09 AM. Shaft begins to appear on the left as top more clearly becomes fibrous, also on the left side (showing that its ice, not liquid).11:12 AM. The shaft is fully developed and the top is clearly ice; has a “cotton candy” look (now termed a Cumulonimbus calvus or maybe capillatus).10:45 AM. Brief appearance of a funnel cloud NNW of Catalina, 5-10 miles.1:14 PM. Lopsided sky. While Cumulus congestus boiled into Cumulonimbus clouds, toward the SW-W were only Cumulus “pancake-us”.1:11 PM. A new round of Cumulus congestus clouds launches off the Catalinas.
Today
We’re still in Floridian=style air with dewpoints, a measure of how much water is in the air around us, even HIGHER than yesterday with several stations from Yuma to Tucson reporting a whopping 70 F dewpoint. Doesn’t get higher than that here, I don’t think. As pointed out, the higher the humidity, the more precip can form in those Cumulonimbus clouds, but also, that greater amount of water, showing up first at cloud base when it condenses, is also like adding a little furnace at the bottom of our clouds. This is because the condensation of lots of water in the cloud offsets the cooling that occurs as the air expands on its way up. That means its easier for clouds to rise up and dump on the more humid days.
However, along with that, the numbers and clustering of these systems is also dependent on favorable patterns high in the atmosphere, like troughs. If they are not there, and its just moist, you can still get yer Cbs, but they may be short-lived, and in the worst cases, send out huge anvils that help terminate other Cumulus clouds by keeping the surface temperatures down.
So, what kind of a day will it be? Large, long-lived clusters with their inches of rain, or localized thunderblasters that burn out fast?
I don’t know, but Bob (our local premiere scientist on convection), and later Mike, his counterpart at the U of AZ, probably will, our true Arizona summer rain experts…
I haven’t got time to get the forecast right, BUT, the AZ Mod seems to suggests big showers today coming up from the S. So, Catalinians, keep your eye toward Orcacle Road into Tucson by later this morning and throughout the day and evening… Could be another memorable day for us.
Every so often something stupefying comes up in the models, such as the extraordinary upper low predicted for over southern California on June 17th. Well, that low disappeared on subsequent model runs, but as of the 06 Z (11 PM AST) run from last night, its back!
But, in that run from yesterday, it wasn’t going to have any tropical air flowing over us; that air was going to end up over New Mexico and Texas.
Things have changed! Now, no less than a hurricane remnant is foretold to scoot up the Mexican coast and be swept up by this low so that its remnants and all that moist air get into Arizona! Check these two maps out from IPS Meteostar. First, the surface weather map. The hurricane remnant is shown just off the tip of Baja Cal (red arrow).
The green areas are those where the model thinks rain has fallen in the prior 12 h ending at the time of this forecast map, 11 PM AST on June 18th, ten days from now. As you can see, the moist plume associated with the dying hurricane, and the entire tropical fetch around this low have been moved westward from the prior model runs and are shown to be entering SE California and Arizona. Fantastic.
Next, is the forecast map that goes with the surface map, the one for the 500 millibar level, around 18,000 feet above sea level. This level shows the steering of the moisture and that hurricane remnant, and that steering (red arrow) is going to take hurricane remnant northward into the Colorado River Valley during the 24-48 h after this map.
Will this happen in 10-12 days?
Almost certainly not like this, but it COULD happen like this. The model outputs have been fluctuating wildly from run to run. But, the ensemble (spaghetti) plots are making the overall situation of a trough along the West Coast in the time frame of 10-12 days, “pretty solid.” And having any trough there is a good thing when tropical storms are along the Mexican coast. They could, along with a good moisture plume, be directed into Arizona.
Hoping there’s some model truth in this exciting display.
Thinking about buying into the wind turbine thing….
Also, I’m hearing complaints about Catalina weather from anonymous sources. First, in late winter, it was “too dry.” Then recently, it was “too hot.” Now, I am hearing, “its too windy, I can’t take my horse out, my baseball cap blew off, etc.”
What have we become?
Hot, dry and windy, as in haboobs, dust devils, straight line thunderstorm winds, happen all the time in DESERTS. I am trying to think of a word for it, oh, there it is, we have become, “crybabies.” Yes, we have become “weather crybabies.” Me, too. It doesn’t rain enough in the desert and I haven’t really seen a good dust devil yet this spring.
OK, look for more dirt in the house today as winds perk up to 40-50 mph in momentary puffs over the next 24 h or so. However, for perspective, Hurricane Bud (110 mph sustained max winds) is about to strike the Mexican coast, so we really don’t have much to complain about in comparison except the fact that the remnants of Hurricane Bud will not come up here, but instead go over to Texas after crossing Mexico. Had this Big Trough causing all the low pressure and winds been a few hundred miles farther west, little Bud might have been swept up this way. Pretty upset by the bad “weather” draw we got so I didn’t want to miss an opportunity to complain a bit.
Take a look at this behemoth trough on the University of Washington 500 mb map for 5 AM AST this morning. Its truly gigantic, and has a really cold core over northern California with snow levels down to. The full loop is here. The clouds of Bud are in the extreme lower right hand corner.
Below this map is the surface pressure pattern showing the huge low center in the Great Basin, like a giant vacuum cleaner up there that is sucking the life out of the air around it and that air to the south of us, hence why that air is rushing northward across us with such enthusiasm; it wants to go right into the center and fill it up.
So why are there clouds and precip? Its too dry, of course, darn it. No tropical air can get to us with such a strong jet stream coming out of the Pacific and around that trough. The Pacific air, where it is deep and moist enough for rain and snow, is constrained within the jet stream core at 500 mb, and that core air will never reach us! Below, this morning’s sounding from Tucson, courtesy of the Wyoming Cowboys, in case you didn’t believe me that it was too dry. If the two heavy lines come together, it would be moist and clouds would be present, and as you can see, that doesn’t happen on this morning’s balloon sounding. And won’t happen, except for maybe rogue lenticular cloud, or, as the Beowulf Cluster at the U of A sees here, a scattered Cumulis humilis of no consequence this afternoon except maybe to produce nice shadows on our glorious mountains. Naturally, cooler air is on its way, too. More details here at the NWS.
