That silver lining referred to in the title, at the top of yesterday evening’s Cumulus congestus cloud in the first photo below. It went on to rain (second photo). But no silver linings in our models now days, if they could have linings. They seem to foretell nothing but dreary, soporific, boring, akin-to-a-science-talk at a major university1, dry weather today through the end of the month.
Forgetting about that tropical storm, Isaac, for the moment, one that seems to be grabbing all the headlines lately, filling our TEEVEEs with endless repetitive reports that could have been dredged up from “file footage”, OUR last hope for rain, it seems, and a good drenching one at that, is from Isaac’s opposite, Elena, a tropical storm now in the eastern Pacific.
Elena might eventually be steered northward and then northeastward with remnants moving into Arizona just after the beginning of the college football season; clouds and rain beginning to affect us September 2nd or 3rd. Where are the headlines about that?
Maybe after all, THAT possibility in Elena is our silver lining for the “dark”, droughty days ahead. Stay tuned.
The End.
6:14 PM. Potent Cumulus congestus builds west of the Tortolita Mountains.6:29 PM. Rain drops out bottom way over there as top surges upward, ice phase in tops quite visible.6:50 PM. Is now pretty much all ice at sunset, dissipated, concluding a disappointing day in which the overnight and later mod runs had rain farther north and over us instead of confined to south of Ina Road.
1It was said by a colleague at the unversity I worked at that, “if boredom could kill, there would be a massacre every Friday afternoon at the department colloquium2.” Perhaps, having given several, I might killed a few people myself…. Unfortunately, the best scientists aren’t trained in how to talk about their work; its a problem we actually know about. We’re too busy to fine tune our presentations so that they are interesting.
2John Locatelli, private communication, late 1970s or so.
Now THAT was a monsoon-like day yesterday, one right out of the western state of Kerala, India; the thick rain of mid-morning, seemingly thicker than most here, the clothes-gripping humidity outside, the strip of fog on the side of the western Ghats, oops, Catalina Mountains, the relatively gentle breezes in the rain, the subdued green hues under the overcast of light rain at the end of the unusual morning drencher, aspects that, en toto, made the morining seem so India-like to me (and I’ve been there in those Kerala rains). Take a look at our green state and State.
10:37 AM, after 0.76 inches of thick rain with occasional thunder. Nimbostratus up top, Stratus fractus along the Samaniego Ridge.10:53 AM. Looking toward Charoleau Gap.
In the Ghats, India, 1975, in case you didn’t believe that I have been in ACTUAL monsoon rains.
And while the rest of the day was sunny, humid and cool for us, the rain wasn’t over with another thunderbludgeoning last night after 9 PM that brought 0.25 inches and the day’s Catalina rain total to 1.02 inches. Drink up, desert!
We also had a nice Altocumulus lenticularis at sunset, suggesting some wind aloft. Seemed almost fall-like seeing this because they are more common with our winter troughs.
6:53 PM.
Another Big Day ahead
3 AM, Arizona obs. Several stations have dewpoints in the low 70s, with TUS reporting, along with light rain, a shockingly high dewpoint of 72 F, really extraordinary.
Get ready! A disturbance over southern California will help organize our storms into ones like those that occur in central Florida today, grouping them into large clusters, with some eye-popping rain amounts likely somewhere in the State (“eye-popping”, 3 plus inches). Don’t be too surprised if you hear about a “tube” somewhere as well. Tubes happen in conditions like these.
After today, its “mostly” dry through the end of September, with the best chance of rain on the 27th-28th.
Nice sunset yesterday, one consisting of_______, _________, ________ clouds, ones that always give us one of those “glad to be here” in Catalina, CDP, feelings. I might give the answers tomorrow, but please try to name these clouds and maybe get that, “Its fun being a cloud-maven, junior” T-shirt you’ve always wanted. It has clouds all over it, maybe even ones you’ve seen and logged!
Only got a trace of rain here in Catalina, though there were a few “be-a-moth” (as we used to say as kids) Cumulonimbus clouds here and there yesterday. Check the U of AZ time lapse movie at about 2:30 PM yesterday for a giant. A couple of examples from around here below:
3:55 PM. Now if we were talking pancakes, this would definitely be a “tall stack.” It was quite a sight, and I hope one of you out there got under this and have a rain report for us today. I would estimate, as you would now, in view of the little movement of the storms yesterday, bases about 8 C (pretty warm), that this giant gave someone 1-2 inches in the peak core.5:44 PM. Here’s a complex of Cumulonimbus clouds SW of Tucson (left of Twin Peaks). The television got pretty worked up about these, as did the TEEVEE weather presenters last evening.
As we know, we are beginning the overall decline in chances of rain each day now; the summer rain season is winding down gradually. Doesn’t mean that in any particular year like this one that it will, BUT you have to give credibility to longer term models outputs that are on the dry side because we’re not dealing with an unbiased coin. The head on the quarter getting flipped for the choice of kicking or receiving in a football game is getting heavier; go for the tail since the heavy head might cause tails to come up more often.
Lately the model runs have had a complete break in the summer rain season around the 25th for a couple of days, then a slow return to wetter conditions alternating with breaks. Go here, to IPS MeteoStar, to see their rendering of the WRF-GFS outputs from last night’s global data, concentrating on the Arizona portion of these maps.
So, what are the chances THIS output, with a reasonable amount of “green” (meteorologists love to color areas of precipitation green; always have and always will) in Arizona at the end of August and the first day or two in September will have summer rains lingering on?
Go next to the NOAA spaghetti factory here. Examine the contours for the end of the month and the first of September…. And, there you have it! Eureka! The confidence level you’ve been looking for.
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.
For a few minutes yesterday afternoon, it looked like some unexpected rain was trucking over the Cat Mountains from the east-northeast late yesterday afternoon. No one could blame you for getting your hopes up and misleading your neighborhood by saying it might rain in half an hour. Those clouds rolling in from the Catalinas (shown below) were great sights for soaring eyes, ones that look to the skies all the time for rain.
5:16 PM. What’s this! Looks like the old Charoleau Gap storm is coming.5:16 PM. Good base all along the Catalinas, nice and solid-looking5:57 PM. Bottom of those weak Cumulonimbus clouds have evaporated, leaving moslty virga, and a sprinkle that reaches the ground over there by those mountains but not here.
But within the hour, the clouds had broken up, and the shower they produced was reflected by a faint rainbow. Rainbows to the east and northeast are often precursors of rain and wind moving into Catalina. Here is the sad remnants of those albeit weak, Cumulonimbus clouds with their feint rainbow, one that was not followed by one drop of rain here.
A big patch of Cirrus kept the temperature down some during the first half of the day, and so our Cumulus were behind in development compared to areas around us. Here is that bad Cirrus spissatus in case you missed it, that which hung over us so long.
It was quite visible even in the visible satellite image all morning. When it shows up there, you can bet that the Cirrus in that image is thick enough to produce shading and mess up the development of Cumulus under and around it, particularly on marginal rain days like yesterday.
Much Cirrus is virtually invisible in visible satellite imagery; get it? You can see it from the ground (i.e., its visible), those thin wisps of Cirrus, but try to find it in a visible satellite image! This whole line of reasoning and befuddled exposition here reminds me of that Science knee-slapper of a few years ago; that article entitled, “Where are the invisible galaxies?”
1:49 PM. Cirrus spissatus, sitting there doing nothing, but wrecking out Cumulus clouds.
Today?
Raining lightly now at 5:25 AM! Yay. A night stalker mass of rain is moving into TUS now as I write. They don’t usually like the daytime and fade as the sun rises in the sky. Sprinkles, very light rain showers (and as always pointed out here, quite emphatically I might add, “sprinkles is not DRIZZLE, dammitall”, to be a little colloquial there!).
Let’s hope this heavy cloud cover we have now (5:30 AM), which you could call, Altocumulus opacus and castellanus due to its height above the ground (its at about 11-12,000 feet above the ground and has turrets here and there). But, to get a little pedalogical you could label it in your log book as Stratocumulus, perhaps with the appendage, castellanus, since turrets are present–those are what’s causing the sprinkles/light showers.
Sunset was nice….
U of AZ mod shows this is our best day for a significant rain, some of that this morning, and some arises later with those afternoon and evening giants we get around here. Hoping so. Tomorrow is supposed to be drier.
Nice sunset yesterday….as some Stratocumulus spread over the sky underneath a pesky Cirrus cloud cover, clouds that announced the beginning of our next rain spell, now underway.
Light rain is falling this morning at 4:07 AM, and has been for hours, amounting to 0.01 inches. However, some places in Pima Land have gotten much nicer rains, around a third of an inch in the Cat Mountains overnight, for example; check here.
Progress of the real monsoon, since June 1st, can be checked back there at the beginning of this sentence. The coastal state of Karnataka has an average rainfall of about 70 inches since June 1st, a below normal amount, believe it or not. However, being a statewide average, that 70 inches doesn’t reflect the hill stations in the western Ghats, surely to have about twice that amount.
Now, as a further aside, Karnataka, Kerala, two Indian west coastal states would be a great place to go for a vacation now! There you could REALLY absorb a REAL monsoon, where passing rains, heavy, pounding, thick with drops, visibility down to less than a mile, go on hour after hour with brief interruptions. Its really pretty amazing and worth experiencing, at least once.
But, not much lightning there, like we have, because the rain develops mainly through a process not requiring ice, much like the rains in Hawaii where lightning is also rare. The rain develops largely through the collisions of drops, ones that stick together after they collide, and get bigger on the way down through the cloud, sometimes called the “warm rain process” because ice is not involved, and that causes most of the rain in that Indian coastal region. Cloud bases are right on the deck, and are typically 20-25 deg C, very, very warm.
In contrast, to continue a pedantic stream, “warm rain” is rare here in Arizony because cloud bases are relatively cool (less than 10 deg C in the summer as a rule), and droplet concentration are moderate to high (hundreds per cc). Higher cloud droplet concentrations make it harder to grow cloud droplets big enough to collide and stick together inside our clouds.
But, we do get that kind of rain, “warm rain” here once in a great while in Arizona as part of the rain that forms in our Cumulonimbus clouds when their bottoms are especially warm, higher than 10 deg C. Seems to happen about once or twice a summer in my experience so far.
What’s ahead?
Now that afternoon and evening rains around the area are back for the foreseeable future (5 days), what’s way ahead, beyond the foreseeable future?
There, as you know, when we start thinking about beyond the foreseeable future we start thinking about spaghetti! What do those crazy northern hemisphere-wide plots produced by NOAA with their dizzying numbers of lines mean for us here in Arizona?
First, I present a map of the 500 millibar contours as produced in the Haight-Asbury hippie district by San Francisco State–I mention this because the lines on this 500 mb map look a little nervous and maybe it has something to do with that map origin, being from a cultural area whose norms are “anomalous.” I have pointed out on this map, “Our Big Fat Anticyclone”, one whose position is critical for decent summer rains here. In this map, as you can see, its not really OUR “BFA”, but rather belongs to Amarillo, TX, as of last evening.
Nevertheless, it is well positioned to fan humid air from the southeast into Arizona, as is happening now. Remember, the circulation around a big fat anticyclone is clockwise. When it sits on top of us, things are not so good; upper level temperatures are high, humidities are low up there, stifling convection and preventing tall Cumulus clouds.
But when the high is away on holiday, temperatures are lower above us, its more humid up there, and those factors allow for deep convection; huge Cumulonimbus clouds. It only takes a few degrees difference to go from those dry days we just had with their Cumulus pancakus, to the kinds of days ahead for us now, where clouds stand tall!
Continuing, finally, Here’s is today’s plot for 15 days from now, the afternoon of August 11th, based on global data taken at 5 PM AST yesterday. What do you see? You see an arrow pointing to something of a void in all the “spaghetti.” That void represents the most likely position of our BFA some two weeks from now, and that position is pretty darn good for summer rains here. And it is in that region, to the north of us, almost the whole time from now!
So, based on this “most likely” position, one would venture that the rich summer rain season we have had thus far, will continue to be active. Of course, this doesn’t mean rain everyday, but that breaks will likely be short through almost the first two weeks of August.
Can you imagine how tall those desert grasses and weeds will be by then if this is the case?
The last couple of photos document our fabulous re-greening now in progress. If you haven’t been out in the desert, you should get out there and experience this wonderful event. Doesn’t happen every year, as we know!
“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.
How great was yesterday with the “return of the shafts”! Though we only received a trace here in Catalina, you knew, if you saw them, that some small areas were getting drenched.
How much?
The Pima County Alert Network indicates that 0.28 inches was the most that fell in their gages. But, from experience, you can bet that somewhere up to half an inch fell on somebody out there, judging by shaft density and the height of the cloud bases–bases were a bit on the high side, at around 10,000 feet above the ground (and moderately cool at 5-6 C) . Will post a radar-derived 24 h rain total map when it comes out (it has) from Intellicast.com. (Gee, there it is and that eye-ball assessment seemed pretty accurate.)
Below are some shots of those glorious, local, late breaking, rainshafts. (Was about to give up on rain in mid-afternoon since Cumulus development had stagnated. But as happens, the atmosphere changes, maybe got hot enough with our 103 F at about the time these boys took off, and, voila, up the tops of those Cu went pretty much all around us.
Note the baby rainshaft below. They’re pretty special. If you were to get in one, you would see that it was pouring rain, but only on you. You could look and couple of hundred yards in every direction and see that it was only raining on YOU. You’d feel pretty special about yourself; maybe boost that self-esteem a bit.
If you want the full review of yesterday’s excitement, go here to the U of A time lapse movie. You’ll see the sky change drastically after about 4:30 PM (if you can read the tiny time hack in the lower right hand corner.)
Today?
The amount of water over us continues to climb, and surface dewpoints reflect that, some in the 60s (61 F here in Catalina now)–meaning a lot of water vapor is around, the fuel of a good rainstorm. The local model run from the U of AZ based on 06Z (11 PM LST) data doesn’t have a lot going on hereabouts, it seems to expect today to be a lot like yesterday–but that would be good.
However, with cloud bases likely to be lower and warmer, that will mean bigger dumps in those rainshafts as more water funnels up into those rising afternoon Cumulonimbus turrets. Hoping for a special e-mail later this morning from the U of A summer rain specialists, always exciting since they only issue them when they think something “good” is going to happen. Didn’t get one yesterday, deemed to tame a day maybe. BTW, “good” is defined by meteorologists as heavy rain, blowing dust from outflow winds, flash floods, lightning, maybe some hail thrown in, etc.
4:45 PM.4:51 PM5:19 PM. Baby rainshaft, so cute! Wish I could have gone over there and stood under it.5:46 PM. Shower line moves southwestward across Marana.7:28 PM. Still going, but in the distance. Nice lightning show out that way until well after midnight.
I got pretty excited when the U of A Weather Department issued a special report yesterday morning on what the Beo Wolf cluster had come up with in terms of yesterday and today’s weather. These kind of special, technical reports, ones that only I can read, not general people, except in the pictures and everybody can read those and can comprehend, are only issued during the best (worst storm) monsoon days. So, it was VERY EXCITING for me to get in this special post in an e-mail. The many model runs had some great thunderstorms and wind building up to the S and SE of us and roaring in across the Oro Valley-Catalina urban complex during the late afternoon and evening. I was pumped. SOMETHING was going to happen!
And, just as the models were thinking, “anvilation” (first photo) began to appear to the south through soiuthwest by late afternoon before the AZCats won the national NCAA Division I baseball title. Sadly, that complex died out before getting here.
Then, over the Cat Mountains, things began to look more promising just before sunset (2nd shot).Cloud bases began looking more solid, not broken up into dark and light patches, and that solidity suggests an significant updraft over a wide area. I thought, “Here it comes!”, since those dark bases were moving off the Catalinas and toward us, possibly pushed by an outflow wind on the other side. This kind of thing, as you know, happens all the time here.
But no, those bases fell apart, they were merely a phenomenon called “Dark Bluster” which nobody really understands, and the only thing that happened from those clouds was a light rainshower over by San Manuel I think, one that produced a weak rainbow (3rd shot).
Oh, well, at least the evening ended with a nice sunset and a national title.
Today?
Hit and miss showers/thunderstorms likely in the afternoon and evening hours again. Nobody knows exactly where they will be so you’ll have to be watching. Actually this is a pretty good deal for later June, often with no chances of rain at all.
Update at 9:17 AM: Cumulus forming over the Catalinas! This is about 4 h ahead of the past two days. Is a darn good sign of more showers/thunderstorms today.
The End.
4:51 PM: Game about to start, complex of Cumulonimbus clouds stretches from S through SW of Catalina.
