Category: Cumulus clouds

Catalina, Florida, USA

Dewpoints above dry ground yesterday of about 70 F at 3000 feet elelvation?  Yep, that’s just like Florida air if you could be in it at 3,000 feet.  And we had Florida-like clouds yesterday, too, with their warm bases, around 15 C (59 F) in the morning–remember how important warm bottoms are for a big rain dump. Warmer cloud bases mean more water up top.

After a couple of grizzily, grudgingly humid days with no rain very close by, we finally got that explosive, much greater coverage of huge Cumulonimbus clouds and some rain yesterday.  Only 0.06 inches here though.  Oh, well.  Lets be happy for well-watered others, if grudgingly.

The cloud signs that the day was going to be very different from the previous two humid “dry” days were there early. The first thunder was heard at 11:45 AM, as one cloud piled into the upper troposphere on top of Mt. Ms. Lemmon just an hour after the first photo below.  Those Lemmon drops produced 1.38 inches at the Pima County ALERT gage there, but a Summerhaven private gage reported 2.46 inches after several storms in the afternoon!

10:48 AM. The day ahead is laid out before you. No need to ponder whether giant storms will abound. Very tall, thin clouds like these tell you that the atmosphere is like a stick of dynamite; only the sunny fuse needs to be lit, and that fuse is beginning to be lit.  I was beside myself with excitement when several clouds like this jetted upward off the Catalinas yesterday morning, their “warm” bases topping the mountains.  As a cloud maven junior, you should have at least mentioned something to a neighbor:  “Man, there are going to be some doozies today!”, and he knows you haven’t even checked with the NWS yet.

Pima County rainfall table  Most:  Avra Valley area, Michigan and Calgary Streets, 2.13 inches.

Other rain totals here, from the U of AZ network.

Later yesterday day, these, a collection of my favorite moments, ones I hope you caught, too.  In case you forgot to log these events, I have filled in some appropriate “novella-sized” captions  for you. I don’t mind if you copy them down as though you had written them yourself… Also, don’t forget to review the awesome U of AZ time lapse movie here, to fill in any other gaps you might have.  Now these photos are going to be kind of scattered around but in that sense, reflect the writer’s eccentricities, and because he hasn’t got time to straighten them out.

11:20 AM. Your log book entry: “First cloud to reach glaciation level, 11:20 AM above Mt Lemmon. I am so excited. This is going to be a fantastic day for clouds.”
11:46 AM. Your log book entry: “First thunder now. The earlier Cumulonimbus capillatus cloud has been replaced by this larger one. I bet Lemmon/Summerhaven are getting pounded. Wish I could be there.”
12:31 PM. “Mt. Lemmon still getting pounded, but sky brightening, looks like the base has been eroded and is not being replaced, not good. Some rain working its way off Lemmon and Samaniego Ridge, but not making it very far. Maybe it won’t even get to me. Feeling sad.”
12:32 PM. “What that over there! I had not seen that while focusing on Ms. Lemmon. That cloud is huge. Look at that base, so firm, so fully packed! This is gonna be a great dump. I wonder if I can get over there in time. Nah, it goes too fast. Looks likes its gonna land on RailX Ranch over.”
12:38 PM six minutes later. “Oh yeah, baby, here it comes! Drops and hail as big as cataloupes! Well, I guess in Arizona, we would say, “as big as gourds!”, figuratively speaking.
12:41 PM, just THREE minutes later! “Feeling sad again that I am not there under this cloud with my raingauge. Maybe a cloud maven junior is there measuring it, keeping track of the time after getting his gage out in it, maybe see if some record for AZ is going to be set, like more than 2 inches in 15 minutes. I guess I can be happy thinking that someone is over there having a good time in the rain.”
12:54 PM. “Rain dump sweeping air out of the way like a big broom. Feeling a little exhausted now as storm reaches peak, likely to fade soon.”

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

In the meantime, more Cumulonimbus clouds form quickly over the Catalinas, but just as quickly fade, the rain getting closer, but only sprinkles have gotten to Catalina by late afternoon.  Then another surprise!

3:13 PM. “Yikes! What’s this coming around Pusch Ridge and out of Tucson? This is incredible-looking! Will set up video, charge camera batteries. No telling how much weather excitement might get to Catalina.”
3:33 PM. “Starting to look ‘biblical.’ That’s always good–‘the end is at hand’, at least of the disappointing dry days.’ I can only imagine how excited the cloud maven juniors are getting seeing this scene.”
3:40 PM. “The cool outflow wind has struck Sutherland Heights, those lower scud clouds riding on top of it. But where is the solid base needed for a regeneration of a huge dump of rain? I want really want to cuss and say, ‘dammitall’, but I will refrain from doing that. And its looking more stratiformy toward the south, like its dying out. What is happening? Is the main development going to propagate out toward Avra Valley again? Am really starting to feel awful now, that kind of disappointment you feel when your team has a 24 point lead at half time and loses by 12. Still looking ‘biblical’ but with your cloud maven junior skills you know its not looking ‘right’ for a big rain on you.”
4:05 PM “It is finished. ‘Biblical’ sky raced by, one associated with outflow winds of that really good storm somewhere else down to the south, and not on me, and it couldn’t push up some new fat bases of clouds that would grow into giant Cumulonimbus clouds as so often happens with the outflow winds. Going home now, kind of dejected. Hoping now we just get any measurable rain. Grasses fading in color now after our dry spell, and suggestion that a new season will soon be here, no more big clouds, adds to dejection and feelings of worthlessness. That’s what a disappointing day can do to you. But as Scarlet said, and we must remember those words, ‘Tomorrow is another day.’ And, we are having some lightning to the west of us here at 4-5 AM. Cool! Getting excited!”

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Today?

OK, have spent some silly time here, now, looking out window, bases low on the Catalinas again. Dewpoints very high. Seems like it should erupt again IF the atmos structure above these clouds is anywhere close to yesterday. Let’s see what the best, Bob, has to say here. Oops, he’s not up yet, but he is the true guru of Cumulonimbus and such that we have here.  Be sure to check back soon!

Sounding from TUS this morning makes it look like its a “go” for giant clouds again, bases as warm as yesterday, if not a little warmer.  Egad, flash flood size.

Finally, U of AZ late night model here also says there’ll be a big day.  Charge camera batteries.

 

The End, finally.

“Dancing Rainshafts”; the movie

While we here in Catalinaland only received a “trace” of rain again from a thunderstorm that sudddenly formed just before 3 PM to our SE-S, there were some tremendous rains in the area yesterday afternoon and evening.  Some examples:

Pima County ALERT precip, max observation:  2.09 inches, Brawley Wash at Highway 86

U of AZ rain map, maximum, as of 7 AM (more reports will filter in during the day): 0.90 inches, N Tucson, see this dump in the movies.

Cocorahs, Pima County max, as of 7 AM (more reports will filter in during the day): 0.64 inches, 2.5 WNW Tucson

USGS, Statewide max 1.2 inches, JD Cabin near Williams.

NWS regional roundup for yesterday; available after 9 AM…

In the meantime, here’s a nice map of radar-derived rainfall, ending at 5 AM today, from the folks at WSI Intellicast:

The most exciting, predictive aspect of the day, that is, how unstable the air over us was, how ready the atmosphere was to allow plumes of cloudy air to shoot upward,  is shown in this U of AZ Weather Department action-packed movie which I shall name;  “Dancing Rainshafts”, because they do kind of twist around each other in this movie in the late afternoon.  One of those is responsible for that 0.90 inches rain in north Tucson around Sky Line Ave.   This is one of the most interesting videos I’ve seen.  Nothing much happens until late morning, and then, “Pow!”

If you noticed at the beginning of the day, when Cumulus started to form on the Catalinas, you saw these incredible, tall, thin clouds, something akin to smoke stacks, plumes from geyers, rising off them.   It was a sure sign the atmosphere would do something special yesterday.  You’ll have to see those tall thin clouds in the U of AZ movie; while I did “document” them in a sense, there was no memory flash card in the camera again, the tiny font alerting me to this fact too small for normal vision.

Still, thanks to the U of AZ Cats, who won their football game on Saturday, you can see it here,  to repeat.

OK. now on to the local cloudscape yesterday….

Here’s what I thought was a surprise, this sequence where a modest cloud glaciated.  Suddenly, after a period of remission in Cumulus activity, this moderately large cloud welled up SE of the house (first photo).

2:49 PM. So-so Cumulus congestus arises to the SE. Am hopeful something will happen, but it doesn’t look so well organized; base a little broken up.  I decided to go into the house and think about something else.

2:58 PM. Amazing! That modest guy has glaciated at the top! I am somewhat shocked. As you know, this means a bunch of snow/rain/graupel-soft hail has formed up there. Fantastic! The next two shots illustrate that this happens, most of the time here anyway, just BEFORE rain falls out the bottom.

 

 

 

 

 

 

 

 

 

 

 

 

Also at 2:58 PM looking at cloud base of the glaciating top (far right) to see if there was yet any sign of a filament of rain, though a few very large and sparse drops might have ejected from it by now (under the far right).
2:58 PM. As part of a photographic burst, here’s a better view of the bottom of that cloud with the glaciating top. No shafts. Here’s an example where, in a burst of converational meteorology you can amaze your friends by telling them, “There’ll be a heckuva shaft of rain coming out of this cloud in about five to ten minutes.”  You’ll be seen as some kind of weather guru. Perhaps you’ll be invited to the next neighborhood party as a result of your new status.
3:03 PM. Shaft emerges. There are striations in the cloud above the bottom if you can make them out. That’s all that precip up there finally being unloaded.
3:08 PM. The shaft at right, such as it is, is fully developed from that modest Cumulonimbus cloud. Other shafts have developed more rapidly.
3:16 PM. The original shaft is just about gone, but look at this coming out! This intensification tells you that a turret had shot upward to far higher levels than the one that started this whole thing off.  The shower has drifted  to the east, too.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The weather ahead….

More of the same every day for the foreseeable future, which is about a week now. Check here. They have a lightning icon in every 12 h period! Fantastic!

But, with all those percentage chances of rain over that whole given in 12 h increments, what IS the chance of measurable rain here in Catalina at some time during that FIVE days?  IF I have calculated it correctly from an example given to me by Mark Albright, Research Meteorologist at the U of WA, it is…drum roll… 96%!

Pattern clouds, a few afternoon drops here, a lot over there, and a nice sunset

Pattern clouds: Cirrocumulus undulatus in odd, parallel lines.  I had not seen parallel lines like this before.  Fragments of Altocumulus are also present.

7:55 AM. Hope you saw this–I ran out of the house since these delicate patterns are usually gone in a couple of minutes.
12:21 PM. Ms. Mt. Lemmon starts to do her thing, send moist plumes of warmer air upward, with cloud remains trailing off to the NW. A southeast flow is present just above mountain top level, giving hope that later, a thunderstorm will drift off the Catalinas toward Catalina.
2:47 PM. Not a great base, but still, it holds promise of representing the bottom of a cloud that can produce measurable rain.
3:09 PM. During halftime I am able to go outside and notice that the Cumulus clouds are still trying to do something, but only light, barely visible showers have fallen toward Samaniego Ridge.
4:06 PM. After the game was over (which game? Dunno, they’re all great) I am able to go outside again and see that a giant cell has formed dropping an inch or more out there to the NW of Catalina. There are frequent cloud to ground strikes. But, there are no more Cumulus above the Catalinas! What happened? End of rain possibility story.

Though only a few drops hit the ground here in Catalina, the day ended with a pretty sunset. This marked the third day in a row where large Cumuluonimbus clouds cells at least an inch of rain in southern Arizona, but we got missed, something that also happened several times in early August.

Some of the moisture doing this is from old, former tropical storm, Elena, particularly the moist plume that resulted in yesterday’s pretty pattern clouds shown in the first photo.  Check the moist plume (whitish stream) from her here.

Looking ahead…..

While Elena was a bit of a disappointment as far as producing rain here in Catalina, her lower level moist plume too far to the west, a sibling storm is arising off Mexico, one that the models (hah!) as they did before, have calculated will cause a renewal of our summer rain season;  showers are foretold for several days beginning around the 3rd as that storm trudges up the west coast of Mexico toward Baja.  You can see the storm and the showers here in this rendering of the WRF-GFS model by IPS MeteoStar.  Remember those green areas on these maps are those in which rain is foretold to have fallen in the previous 6 h (later in the run, in the prior 12 h).  There is a LOT of green over SE Arizona after the showers begin to occur by the afternoon of the 3rd.

As is commonly heard these days from people concerned about drought, “think green”!

 

 

 

6:40 PM. A little hole in the clouds allows the late evening sunlight to penetrate into the aerosols we have over us, thereby producing an orange ray of sun.

Catalina miss, but an inch just next to Saddlebrooke

I guess we can be happy for them…  Here’s how the day went.

9:39 AM In case you missed logging this special cloud, Cirrocumulus undulatus, waves in the atmosphere.
9:40 AM. I guess you could have been distracted by the first Cumulus rising off Mt. Ms. Lemmon.
12:07 PM. Nice progression to our Catalina cloud street off’n Lemmon, but slower to grow than the day before. Reason to be concerned.

 

3:08 PM. The local picture begins to improve as a Cumulonimbus with a strong rainshaft forms N of Catalina and Cumulus congestus arise away from the Catalinas.
4:23 PM. Now this is really looking fantastic! Its going to dump for sure, and while this Cumulus congestus base is to the N of us and moving away, the ensuing outflow winds from the falling rain might well cause clouds to back up against the wind and new heavy Cumulus might form over us!
4:33 PM. “Dump, der it is”, paraphrasing the popular ditty from “In Living Color” that emerged at ball games, “Bloop, there it is”…  Now, lets see what the outfloiwng wind does.  Can it move that dark region this side of the rainshaft thisaway? I sped off to Sutherland Heights district to get a closer, electrifying look.
4:43 PM and 20 photos later…. This is looking fantastic, at least, over there by Saddlebrooke.
4:50 PM. Someone’s getting ver wet over there. A Pima County ALERT gage reported 1.06 inches under this. But, the dark cloud base on this side has thinned (take a look above the partial rainbow). Its over for Catalina as far as outlfow winds pushing up a new base.
5:15 PM. While pretty to look at, the tattered clouds to the left of the rainshaft are telling you “its over.” Now, the only question that remains is whether there will be a nice sunset?
6:50 PM. And the answer to the sunset question was yes.

“WeathKit”

Got up a little late (4:06 AM), got behind, feeling kind of lazy, and then started thinking about Heathkit, Benton Harbor, MI.  Perhaps you, too, had put one of their electronic kits together, ones that smoked after you plugged it in, like me.  Oh, yeah.  That was exciting!  Perhaps I could do a “Weathkit” in the modern era.  You would order it, being interested in weather and clouds as you are, and it would come in something like a shoebox, but then there would only be a thumb drive in it with a bunch of links for you to assemble your own weather forecast.

At first, of course, you’d be upset because you paid me so much for a thumb drive and complain that the packaging was overdone, misleading.  And then on the thumb drive there would be, say, several links.  They would be tuned, of course, from the region from which you ordered, except maybe one which would be a more general, global  link in case you wanted to check the weather in world trouble spots.  Lastly, there would be one to help you with the “final product” in case you bungled the whole thing like I did with my many Heathkits.

The links wouldn’t be labeled because that would be part of the joy of assembling your own weather forecast from them.  You’d be so excited just to click on each one and see what it was, some of the fun and appeal of “Weathkit.”  A prototype is shown below.  Let me know how much you would pay for these on a 1 GB thumb drive….

Link1

Link2

Link3

Link4

Link5

Link6

Link7

Link8

Link9

Thanks; your opinion is important to us here at WeathKit (pronounced “weth-kit”, NOT “weeeeth-kit”, dammitall!)

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Got a trace of rain yesterday afternoon just after noon as a matter of fact, as Cu congestus piled up over the Cat Mountains and drifted over Catalina from the ENE.  The day started much more promising than it ended up since cloud bases had lowered substantially from the prior day and were now just above the top of Ms. Lemmon.  Rain had not been predicted at all the previous day and so the occurrence of even a trace was a bit of a model fumble, a flub.  And, if you looked around, MUCH heavier showers were nearby.

12:01 PM. Nice cloud street streams directly overhead giving promise of a shower.
12:02 PM. Twin towers show further indications that the cloudy air was going to reach great heights yesterday.
12:19 PM. Its raining from this, pretty early for a rain shower. Maybe we’ll have something great later on!
2:49 PM. Large, but sloping Cumulonimbus calvus forms N of Catalina, top bubble is just now beginning to show the transformation to ice. No rainshaft yet.
12:49. Closeup of that glaciating Cb calvus top. “Calvus” means “bald”, BTW.
2:55 Pm. Its got the big shaft now, but the sloped aspect says this Cb has pretty weak updrafts in it and may not last long. Remember when we used to see these weak Cumulonimbus clouds and sing, “Hang on, slopey, slopey, hang on, da-dum-da-dum-da-dum”, because we knew ones like this probably wouldn’t last?
5:58 AM today! Here’s your sunrise photo, Altocumulus perlucidus, in case you were too lazy to get up and see it. Now, get going on your forecast…

Silver lining

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.

Not expected, but it missed anyway

Woke up to Cumulonimbus clouds NW-N of Catalina.  Hmmm.  Here’s the unexpected, pretty sight just after sunrise:

7:24 AM. “Pretty, but will likely die much after sunrise.” Cumulus and Cumulonimbus clouds along a windshift line moving toward Catalina continued to develop throughout the morning while getting closer.
9:34 AM. Odd line of Cumulus congestus growing into Cumulonimbus clouds with major rainshafts is getting closer still. “What’s keeping this going so early in the day?”

 

10:00 AM. “Upon closer inspection….”, a windshift line is detected via photography!
Arrow point to shred cloud below base of the turret at left. This is a great example of how clashing winds build clouds. Above the shred clouds is that vigorously growing turret trying to reach the glaciation level.
10:06 AM. It made it! (to the glaciation level)  Maybe it means that the line of fat Cumulus-Cumulonimbus might make it here to Catalina and rain on me! I’m getting excited. Arrow points to icy top, though as cloud maven juniors you would already recognize that icy top, so I left the arrow out since I forgot add it anyway.  These are the best kinds of icy tops to study with an airplane because they near the threshold temperature where ice forms in clouds on this day.  That threshold level changes from day to day, strangely believe it, and the warmer the BOTTOM of the cloud, the HIGHER the temperature at which ice forms, strangely believe it#2.  Even stranger, Mr. Cloud-maven person thought he had discovered this interesting fact back in 1988 and then he found that this guy, the Englishman, Frank Ludlum, one of the best we’ve ever had in cloud studies, and I should have known better, had reported the SAME THING 36 years earlier in 1952!  There is nothing new under the sun, Ecclesiastes said, and I guess I found out first hand.  Darn.  I laughed bitterly when I saw that Science mag cartoon about stuff like this, posted below because it won’t fit in this caption.  Darn.  You can see I still have some feelings about having something to report but then finding out that it had already been reported. I thought maybe I was gong to be famous, perhaps win a prize of some kind, but no.  (See second cartoon)


Well, the end of the story (told in the captions) is that a windshift producing this line of heavy Cu and a Cb or two and it “struck” Catalina about 11 AM;  the wind turned from the SW to the N, but the heavy line of clouds riding it were nowhere to be seen at that time; the last Cumulonimbus cloud disappearing beyond the Charoleau Gap. Tough to take after hopes up.

Only in the early afternoon did a gift of a few drops from a towering Cumulus directly overhead produce the final surprise. The drops fell from 1:22 PM to 1:23 PM. I rushed outside to see what the heck was doing it and here that cloud is (last two photos) from the bottom up.

1:23 PM. Its raining!

 1:23 PM also. Arrow points to ice, showing that this little guy got to the ice-forming level, and would have been another great subject for an aircraft study of ice formation.

Mods see afternoon isolated Cumulonimbus today.

The End.

Big fat Cumulus day

4 AM to 4 AM 24 h totals ending today, ones that catch that morning rain (except where noted):

2.12 inches near Chrysotile, AZ, NE of Globe.

2.06 inches Wet Beaver Creek, Oak Creek Canyon area.

1.85 White Tail, just west of Palisade RS off Catalina Highway.

1.39 Oracle Ridge near Oracle in Cat Mountains

PHX set daily record ending at midnight last night, 0.80 inches.

Here’s the AZ radar-derived rain from 5 AM to 5 AM from WSI Intellicast:

Catalina?  A crummy 0.07 inches.  Well, no rain is technically “crummy”.

Good chance that some or all of that rain yesterday morning fell from clouds not having any ice in them, that is, formed rain due to the “warm rain” process, a rarity in AZ.  But, without an aircraft, its a dicey call.

1 PM Catalina temperature and dewpoint:  86 F and 73 F.  Miami, FL, at the same time:  90 F, 72 F. Warmer and dryer in Miami at the same hour. Our dewpoint was higher here than in Miami, quite something.  Our high dewpoints were helped by all the rain water evaporating yesterday against a background of already very moist tropical air.

The air was extremely humid here, but not hazy like back East on humid days. Interpretation? The air was very clean.

Its not the end of summer rain season even though a few dry days are ahead after today.

Cloud bases in the morning clouds were running 16-17 C, about 62-64 F, which means those clouds had about as much water condensed in them near their tops as any cloud could possibly have here.

AZ mod (here) thinks it can rain here in the late afternoon today.  Excellent.

Some of my big fat Cumulus cloud shots from yesterday, ones that were just like ones in Florida and Gulf Coast this time of year.

7:24 AM. Warm-based Stratocumulus clouds with embedded Cumulus build ups produce intermittent rain along the Catalina Mountains.
9:36 AM. As the Stratocumulus layer dissipates, gigantic, low-based, Florida-style Cumulus clouds begin arising NW of Catalina.
9:48 AM. I can hardly speak, these clouds are so HUGE! How many inches of rain might fall from them? Note glaciated tower protruding above the mass; top, right of center.
10:04 AM. Larger yet! Note low scud clouds, seemingly just above Saddlebroke rooftops.
10:09 AM. While these were wonderfully tall and low-based Cumulus congestus clouds, something was going wrong. Why weren’t there Cumulonimbus clouds, anvils scattered here and there to the SW-W?
11:15 AM. It was getting worse. It was clear that drier air was moving in aloft and dessicating growing clouds. Cumulonimbus were still peppering the area just NW of Catalina, but they were shrinking in size as cloud bases rose.
1:23 PM. The Cumulus congestus clouds lined the tops of the Catalinas, and occasionally produced a glaciated turret, but nothing gigantic as had been expected earlier in the morning.
1:32 PM. Glaciated turret (center) pokes up behind Cu congestus tops over the Catalinas. Would have been raining like “heck” under it.
2:26 PM. Though a big rain did not come through as I thought it might, it was a fabulously photogenic day with scenes of our now green desert topped by those puffy, roiling Cumulus clouds dotting the sky, ones providing thoughts of rain.

Yesterday’s “be-a-moths”; what’s ahead in August and early September

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.

 

There were several reports of more than an inch yesterday in the ALERT raingauge network.

What’s ahead?

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.

The End.

Ka-blam! 1.07 inches, most of it in half an hour.

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)!