Sky to do to a lot of things today

Keep cameras at the ready.  Have some nice lenticulars in the lee of the Catalinas this morning if u look.

FROPA (weather text for “frontal passage” and cold air burst into Oro Valley and Catalina likely to be fronted by a lower arcus-like cloud that comes over the Torts later today.  That should be dramatic, though personally I will complain about cold air right after it hits.

Still riding the forecast wave  of 0.3 inches, though mods have varied from nothing to about that now.  Yay!

 

Since its already windy, there’s a good chance of more windy (from the SW) right up until FROPA when the wind will turn to the NW for a while.

The End

The top 100 weather blogs; the weather ahead still filled with rainy portent

“Rainy portent”;  is there a better phrase for a desert than that?  I don’t think so.  See mini-discussion below, and below that, some soapboxing!  Very excited today!  Where are my pills?

Now, let us discuss the top 100 weather blogs:

Bob Maddox‘ superb site,  representing Tucson, makes the list ! This note and info from pal and fellow weather fiend and fellow science investigator, Mark Albright1:

Top 100 here

“Some notable blogs in the list, Mark notes:
 1) Watts Up With That
 2) Roy Spencer
11) Cliff Mass Weather and Climate (U of Washington Huskies!)
28) Judith Curry, Climate Etc (once worked at U of Washington Huskies as a visiting grad student
30) RealClimate  (from the Huskies)
33) Wasatch Weather Weenies, Jim Steenburgh    (graduated from from the U of Washington Huskies!)
65) Mike Smith
70) Madweather – Bob Maddox (Tucson AZ) (Was grad   student of mighty prof and neighbor, Bill Cotton, whose heard of the Huskies!
83) West Coast Weather – Michael Fagin”
 
Not sure if “we” (to distribute poor performance beyond a single author) even made the top 1000; the list doesn’t go that low (or high). 
 
But, we’re not really a weather site, per se, to put a positive spin on a glum finding.  We talk mostly clouds here. not so much weather.  Contains sophomoric, droll, and tongue in cheek “humor”, too.  Maybe Cloud Maven Person’s blogulations would make the top 1000 CLOUD sites!

 The weather ahead and beyond ahead

Cool with passing rains every coupla to few days, maybe some snow with one of those events, as they continue into February.  The first storm begins on January 20th, and then its one threat after another.   This new “troughy” regime should bring the January rainfall total in Catalinaland over average of 1.60 inches (1978-2017).  Currently, we’ve logged 1.10 inches in a NWS style 8-inch diameter gauge. 

Looking for tiny green sprouts out of our desert soil now.

The End

(except for all the footnoted sci commentary below)


sci commentary and soapbox module——

1Mark Albright routinely calls attention to suspect temperature data that’s out there, and other questionable aspects of some climate statements2.  He is widely well thought of for these conscientious efforts in bringing temperature errors to people’s attention3.   Mark was former State Climatologist of Washington State, to be redundant, for many years.  Was more or less fired for questioning claims of HUGE snowpack losses in the Pac NW between the late 1940s/50s (a cold era that started after a warm era in the 30s and 40s) and the late 1990s (a Niño-filled warm decade); to wit, it was a cherry-picked study,  as we learned later via Stoelinga et al 2010 pdf, and by the mountainous snows that  occurred immediately after that bogus claim was published in the Bull. Amer. Meteor. Soc.

Could snowpack go down gradually over the years in the Pac NW due to warming? Sure! But there was no need to cherry-pick data to create the appearance of an imminent calamity! It destroys credibility when objective investigators like Stoelinga, Mass, and Albright check into them.  Michael Mann, of Penn State and “hockey stick” fame, also fueled the fires of skepticism and doubt needlessly by refusing to give the details (data and methodology) on how he created “The Stick” which eliminated such climate anomalies as the Medieval Warm Period and the Little Ice Age that followed.  If you read Science magazine, they often refer to the MWP and LIA!  What’s Up With That?  It can’t be both,; didn’t happen but did happen????!!!!!  Dammital.

“Fellow investigator”, CMP? Oh, yeah, baby! Your CMP likes questioning exaggerated cloud seeding reports after they’ve been published in peer-reviewed journals!  Or checking into suspect cloud reports *(after all, he is the “Cloud Maven”) that are the foundations of seeding results. He’s even gone to foreign countries (well, one) to check out suspect cloud reports, help the people of that country understand their clouds.

While CMP   has a number of peer-reviewed pubs  that are critical of cloud seeding (nearly all co-authored with the late mighty Prof. Peter V. Hobbs),  maybe today,  as do so many good scientists and others,  those critiques would just be in blogs?  I dunno.

Journal editors have tremendous power over your getting in these days via who they give your manuscript to to review.  (Well, that’s always been the case).

But today that power has grown enormously since they (a single  editor or an editorial board) can refuse your manuscript on first sight (its “D. O. A.)” and not even send it out for peer-review! This is an intolerable situation since non-objective factors will certainly creep in to such a process.  As an example of unwanted but valid science, Stoelinga et al took years to get into the J. of Climate.

Note to journal editors: Send the damn thing out! Let legitimate, even adversarial reviewers,  determine the fate of a manuscript, with the stipulation that the author (s) have a chance to rebut adversarial reviews which will likely reject a manuscript prima facie. They’re the best ones!

And, no “pal reviews”! They’ve cost us so much in the early published cloud seeding claims here, and in Israel , believed to be accurate by our best scientists and national panels, but cost us and Israel  tens of millions of dollars of worthless cloud seeding based on those ersatz published results.

2Some professors and students at the U of WA delete Mark’s e-mails on arrival; they prefer not to hear about discrepancies or other weather data that might cast doubt on today’s climate issues.  As far as I know, only Prof. Cliff Mass has,  from time to time,  openly supported Mark’s findings putting him even more in the cross hairs of some of his fellow faculty members and especially some other climate scientists and students/post docs since he has often scrutinized and found wanting  some gross claims on climate change.   We are in a science era where questioning  even the magnitude of the warming ahead, even if we believe its coming,  is seen as untoward.  Science is not as it should be!

3If you believe that, I also have some ocean front property in Nebraska I’d like to sell you.

Regime change still ahead, as are more Cal blasters

Check it out, spaghetti1 lovers:

Valid at 5 PM AST, January 20th. Bulges toward the Equator indicate areas of stormy weather in “troughs” and we’re in one! Will January have above average rain in Catalina? I think so now. How much is that? Oh, only 1.53 inches and we have 1.10 inches now.
Valid at 5 PM AST on January 24th. A second trough with its stormy weather, or threat thereof, is indicated for Arizona and the SW! These storms look strong coming into California, representing good news for filling reservoirs after the early winter drought, but bad news for mudslides in those huge burned areas. The last storm produced 4-7 inches in 24 h, with rainrates sometimes exceeding an inch an hour, about as high as they get in wintertime in Cal.

So, enjoy the warm, dry spell we’re in now, if that’s what you like and that is why you are in old AZZY, since you probably won’t be as happy after the 20th or so.

Pretty excited about this change coming up, one that will break five months of below average rainfall here in Catland with January’s total likely to be above average now!  Yay for desert greening, too, that soul-filling spring phenomenon we all need as much of as possible.

The End

—————————-
1You can go here and see the whole sequence from the NOAA spaghetti factory (aka, ensemble factory).

Sutherland Heights rain total ponies up to 1.10 inches!

That was about three times more than CMP (me) expected, and it was such a fabulous a rain!  That soaking amount should start the spring greening that we love here.   With more rains in the pipeline, eventually, after another longish dry spell, maybe the spring bloom won’t be as bad as it once looked.

As we who love the Sonoran Desert know,  its a pretty special place when it comes to rain.  But only recently did I learn that the SD is the ONLY desert in the world (!!!) with TWO rain seasons, so great for a cloud-loving meteorologist1, though three or four rain seasons would be that much better.   Now, after some interesting information, clouds: yesterday’s, of course:  a study in gray2, more or less.

Yesterday’s clouds

7:53 AM. The sky had kind of a mellow gray cast to it as the day started, not much detail as rain falling out of the gray clouds obscured the usually ragged bases. This is a very peaceful scene if you stare at it for ten minutes, letting your mind empty all of that clutter in it.  This clutterless scene will help…
8:11 AM. Misty rain continues to fall from Stratocumulus clouds, though Nimbostratus would be an OK name, too. Cloud tops were beginning to come down.  Those shred clouds might be called, “Stratus fractus”, to add more unneeded detail.
9:27 AM. A great example of Stratus, hardly any detail can be seen at the bottom. Also, drizzle was falling from this layer (as can be seen in the slight bit of “haze”). Tops were really coming down, and its likely that no ice was involved. For some reason, this scene, looking across Oro Valley, appeals to me, though it might not be for everyone.  You felt you could almost reach up and grab some of of this Stratus, it was so low.
9:31 AM. The study in gray continues. This heavier, but still light rain, implies that it formed in deeper, mounding tops. Still doubtful that ice was involved, but really don’t know. If I had that Lear jet at my disposal, I could have maybe gone up and been able to tell you. I wonder if crowd funding could get me one?
12:44 PM. Am sensing gray fatigue in the reader, so need to break up the gray with something. This coyote was pooping in the middle of Equestrian Trail Road when I came around a corner. I felt I had to stop and let him finish. Then he just kind of sauntered off, in no hurry. Maybe he was thanking me, too.
2:08 PM. All rain had ended, cloud tops descending below the ice-forming level, and the winds aloft were coming around from the west. Often a cloud street launches from the Tortolita Mountains in these situations as we saw yesterday.
4:45 PM. Eventually the Stratocumulus began to open up and allow those wonderful highlights and shadows on the Catalinas. You can never tired of scenes like this!  Well speak for myself, anyway.
4:46 PM. Nice.
4:46. Zoomed view of nice. Nicer.
5:14 PM. We’ve been so long without low clouds, I have to overdo these lighting shots today.

And then the great sunset of underlit Stratocumulus clouds…

5:46 PM. No words required.

Notice that in the afternoon shots, no virga or ice was seen in any cloud!  What up with that?  Well, of course, if you’ve been coming to this site, you will know its because the cloud tops have descended to something above -10° (14°F) or so where ice begins to form naturally in these  parts on most days.  (There are exceptions, such as when drizzle or rain drops form in clouds; then ice can form almost spontaneously and readily at temperatures higher than -10°C, and that may have happened as yesterday’s storm ended.)

But, in a  further educational (?) diversion, here’s the TUS sounding launched from the U of AZ around 3:30 PM yesterday (goes up at about 1000 feet a minute, btw).

This demonstrates the fairly warm tops of clouds during the afternoon, ones showing no ice. I wanted to show this so I could be right about something after missing the rain forecast by a factor of three…  In spite of all the clouds around, there were no echoes in practically the whole state of Arizona at this time!  Pretty remarkable.

The weather ahead and beyond

Still looks like a regime change is in the works after our dry spell, one that ends around the 20th.  At that time it still appears that winter will take on a more normal aspect; a few dry days followed by rain/snow threats, that is, not weeks of dry spells!


2One of the interesting things about me is that my favorite color has always been gray; even in grammar school when I crayola-ed gray skies instead of a blue one with the sun stuck on it somewhere like the other kids did.

Sutherland Heights rain: 0.97 inches and counting (as of 9:54 AM)! Thunder, too!

What an amazing and “productive”  little rainband that was just after midnight!  And more rain is likely with weaker bands just upwind here at 4 AM.  Could we really approach an inch?  Amazing.  Didn’t seem possible in this small mind that we could amass that much.  For a full regional rain table, go here to the ALERT gauge records.

An even more dense collection of rain totals can be found on the Weather Underground map for the Catalina/Tucson area *click on the precip button when you get there, radar, too).  We seem to have done better than just about anywhere else in the state, with 2.94 inches at Biosphere 2 leading the way (thanks to those “TSTMS” and the rain gushes with them, I am sure.)

Now, after this ends, a long dry spell has to be endured, at least until around the 20th of Jan, at which time we hope the troughs and rain threats at least,  will begin to barge in every few days, namely, and pattern more typical of winter sets in.

Yesterday’s clouds

8:31 AM. Typically lenticular clouds form in the lee of the Catalinas as storms approach. Lenticular clouds are good signs of deteriorating weather ahead since they are usually accompanied by strong, moistening winds aloft.
8:31 AM. Zoomed view of one lurking just beyond the crest of Ms. Mt. Sara Lemmon. The higher clouds were Cirrus (which can have grayness when the sun is low).
10:24 AM. Wasn’t long before this deck of Stratocumulus raced over the sky, adding that feeling that rain is a comin’.
11:32 AM. Some tendency to form the new supplementary cloud feature, termed, “asperatus undulatus” is shown here at the base of the Stratocumulus deck.
1:13 PM. Got excited when ice began to show up, with virga and light rain showers here and there.  Can you see that icy top receding from the Catalinas?  It wasn’t that high and cold, either.
1:14 PM. Nice highlighted view of Biosphere 2, with light rain showers in the background. Whodda guessed Bio2 would get 1.93 inches overnight? Not me!
1:59 PM. Light rain showers began to fall from that Stratocumulus layer, now pocked with buildups (Stratocu castellanus?) as temperatures aloft above cloud top cooled.  The haze is due to rain falling from overhead.  It did not measure.
1:59 PM. Looking upstream and the Stratocumulus deck whose tops were just ascending to the ice-producing level as they approached Catalina from the SSW. That clearing on the horizon maintained throughout this cloud and shower period suggesting it was caused soley by the lifting of the air as it approached the higher terrain of Catalina and the mountains. It was soon to disappear.
3:02 PM. Falling apart.
3:49 PM. Gone.  Yes, once again, the clearing before the storm.  A storm is approaching, 100% chance of rain within 10 h, and yet, the clouds are disappearing!  This is a common here; a dry slot in the moisture field OFTEN precedes storms here.  To some folks it may mislead them into thinking the storm’s a bust.  But not to us CMP’s, who seen this happen over and over again.
5:09 PM. Temperature’s in the low 70s; its getting to be a nicer day by the minute. Where’s that storm?
5:43 PM. Our storm and cold front marches toward us from somewhere over the horizon, though visually you’d never know it.  Wonder if the native Americans knew this odd sequence–probably.

The weather ahead

After the last drops fall today, we’ll suffer through another dry spell and warm up though about the 20th when a major trough passes by.

The End

Oops….  Have cameras ready for a great day of cloud shots once the sun breaks through.

Sun and Altocumulus clouds combine to provide a colorful sunrise and a sunset on the same day! Rain on tap!

“Rain on tap” does not  refer to a microbrew, for those who’ve accidentally stumbled onto this site.

Our nice sunrise and sunset, featuring supercooled1  Altocumulus clouds:

7:22 AM.
7:26 AM.
7:29 AM. Ice crystals trail down from this region of cloud cover toward the north. Was it hers or ours? This Altocu layer was at -15°C (about 4°F), cold enough for some natural ice, but not as prolific as this. The fact that the ice does not trail downward much indicates the crystals in this virga were really small, also suggesting a non-natural event since an aircraft can produce thousands per liter of ice crystals, none of which can grow to very large sizes. Maybe ours?
9:20 AM. Well, what’s a day in Arizona with supercooled Altocumulus without an ice canal caused by an aircraft. So, they were occurring yesterday.  We don’t see them much in the summer because the Altocumulus clouds are warmer.

 

4:36 PM. Our steady diet of Altocumulus yesterday is topped here by a veil of CIrrostratus, all leading one to expect a colorful sunset.
5:52 PM. So pretty again….

 

5:52 PM. Wider view of the same scene.

 

Rain on tap?  Oh, yeah….finally.  One forecaster friend is predicting 0.5 inches!  How nice would that be?  The rain will likely begin toward midnight–check it here from our nice U of AZ Weather Department.

Looking for more rain in AZ after mid-month, toward the 20th.

The End

Cloud patterns excite Catalinans; storms continue to pile up for January

A swatch of Altocumulus perlucidus translucidus (sorry, that’s the way we talk around here) passed over Catalina early yesterday afternoon, each “unit” nearly perfectly evenly spaced with its fellow cloud element creating a brief period of cloud awe for those Catalinans (or is it, “Catalina-ites”?  “Catalinians”?  Who knows, who cares?).  Here it is, in case you work indoors and missed it.  It was truly a fabulous sighting!

1:16 PM.
1:16 PM. Starting to take too many pictures of the same thing!
1:16 PM.
1:16 PM, of course.  So pretty.

The afternoon was marked by a melange1 of middle clouds:

1:52 PM. Altocumulus opacus with a Cirrostratus above.
3:11 PM. Some equestrians on horses (haha) went by the house.  Sometimes we focus too much on just clouds here, and so we offer the reader who visits here an occasional relief from cloud fatigue.
3:12 PM. Those equestrians were being shaded by a Altcumulus perlucidus and by an overcast of Cirrostratus.  If you look real hard, you can see a faint halo.  The Cirrostratus was thickening upwind as an upper level wave approached and was increasing the amount of rising air aloft over us. The Altocumulus clouds also thickened toward sunset.  See below.
5:07 PM. Heavy Altocumulus approached from the SW, keeping the sun from under-lighting the Altocumulus as it went down, so no flaming sunset last night. The Cirrostratus overcast continues. All in all, a fine day for Catalinians!

The weather just ahead

The local TEEVEE met men are, of course, pounding out the good news rain is just ahead for Catalina.  Looks like, oh, 100% chance to CMP (Cloud Maven Person) starting after midnight Tuesday to Wednesday.  How much?

This is a potent, but fast moving trough.  Maybe will have only 2-4 h of rain with the passage of the cold front and its rainband.  But, coming from the sub-tropics, should have a appreciable rain band with it.

I would expect rainrates to reach “moderate” as the heart of the band goes by for a coupla hours, anyway.  Moderate rain is defined by the NWS as 0.1 to 0.3 inches per hour.  So, only two hours of moderate rain should be at LEAST  0.2 inches, and most likely more.

We’re thinking here that there’s a 90% chance of more than 0.15 inches, and a 90% chance of less than 0.70 inches.  So, averaging those two leads to a best estimate in CMP’s opinion of 0.425 inches!  Wow.  Nice.

Now, I will look at the U of AZ nested model and see what it thinks.  Kind of game we play here, seeing how a seat of the pants forecast, made over a coupla minutes, measures up to a computer model with billions if not trillions of calculations:

Cumulative rainfall ending at 3 PM AST Wednesday afternoon. Catalina is in the GREEN, indicating that the Beowulf Supercluster thinks we’ll have over half an inch (Ms Mt. Lemmon, over an inch!) I am so happy!

The weather way ahead

After the nice rain just ahead, we have to get through the week-long dry spell before we move into a new stormy regime.  First, a spaghetti depiction of the ridge after our nice storm:

Valid at 5 PM on the 14th. Huge ridge has stacked up along the West Coast, making it look like the drought will continue ad nauseum.  You’ll be discouraged when the middle of January comes around (though by then, everyone will know this is a straw ridge, will collapse in almost hours from this time from the outputs made in real time then.)

Here’s what’s been exciting for a few days now, and below, from last evening’s global model output:

Let’s see what the actual and very latest model run from IPS Meteostar has for us:

From the 11 PM AST last evening global model output this big boy. Unlike so many prior troughs that were bogus this winter at this time ahead (two weeks), this one has spaghetti support and will be real!!! And, it won’t be the only one!!! I’m shouting again!!!

How much these coming rains can benefit our spring wildflower bloom and spring grasses I don’t know, but I sure hope they can resuscitate what otherwise will be a dismal spring.

Expecting a snow event during the “new regime” that takes over after mid-month,  too.  Be ready!

 

The End

Trace of rain ruffles drought in Catalina! New storm approaches in five days or so followed by a several day dry, warm period followed by more storm threats a few days after that; January beginning to look wetter than December though it wouldn’t take that much rain to exceed Deember’s meager total of just 0.27 inches

Yep, unless you were outside yesterday morning, you probably missed the few drops that fell.   But fall they did, giving us officially a trace of rain for January!  In case you don’t believe me, here is a shot of the incoming shafts of rain.  OK, “veils” of rain.

8:22 AM. Rain reaches the ground from thick Altostratus/Altocumulus clouds.

Now, a historical forecasting criteria note after that paragraphical blog title, a criterion that still holds true:

In the 1950s and 1960s, the Los Angeles forecast office used the 564 decameter height on  500 mb weather maps (those made for about 18,000 feet above sea level)  to delineate where the rain line was for incoming troughs.  North of that, rain fell; south, no rain.
It was remarkable how well that worked.
Don’t know it that height criteria holds here in AZ, probably not, but the 500 wind max seems to be a good discriminator for TUS for rain; under or north of that max seems to be a necessary (though not sufficient) criteria in wintertime.  (That wind max does not hold in Cal; rain often falls south of the 500 jet max; only east of the Sierras and coastal ranges does it hold.)
Lately, as winter gets colder,  the NOAA spaghetti factory has recently lowered the red line heights to 564 dm in their 500 mb spaghetti plots, you can see that in 5 days from last night’s 00Z run, rain is virtually assured in southern Cal using that criterion, and we hope that rain gets here, too.
Check out where red lines are in the plot below.  I’ve helped you to find red lines on this plot by annotating them with an arrow:
Valid at 5 PM AST. See red lines. See red lines move east from California.
But after that trough whooshes by like a Nike logo, in ten days (2nd plot), we’re doomed again to be in the midst of a long warm, dry spell:
Valid on January 14th, at 5 PM AST.

But what about after that next warm, dry spell?  The weather way ahead

 In a less professional comment than the usual ones posted here, reaching beyond the 10 day forecast limit, that domain of the models where things that are forecast beyond ten days often go to hell with just the next model run, these spaghetti plots foretell a collapse of that big fat, storm blockin’ ridge after our next warm, dry spell!  It collapses into a muddle down, oh, I dunno, way down in subtropics somewhere.  Yay!  I can feel your happiness as I write this for you!
That ridge collapse means, first of all, that strong storms will blast Cal with needed flooding (well, big rains, anyway), and its likely that those Cal blastin’ storms will reach into all of Arizona providing a much needed hiatus in our drought, that is, will bring appreciable rains right here into Catalina as well.  You can see if I have made this up by looking at the whole sequence here, keeping an eye on where those red lines are foretold to be.
So, that’s it, that’s my take on the longer term weather pattern:
A Change Gonna Come,” as so eloquently sung by the master, Sam Cooke, when that 500 mb criterion was being used in LA, and apropos here because a change is gonna come, not that long from now.    (Warning:  The historical video scenes with Sam’s heartfelt tune will bring tears I just learned…  Everyone should see it.  Yep, we’ve been through a lot since he sang that song….)
Will keep you up to date every so often if it looks like my take, cribbed from the spaghetti plots is going to be correct in that  drought bustin’ part I’ve described beyond ten days. In the event this “take” goes bad,  it will, of course,  not mentioned again.  May have to fall back on writing about aircraft ice production in supercooled clouds to distract you.
The End

Artifact skies

I use that expression not only to draw attention to myself since my name is Art, or, “Artie boy” to mom, but also because I had a role in bringing this phenomenon to the attention of the scientific community; that is, that an aircraft could glaciate portions of clouds at temperatures as high as -8°C.  This in a peer-reviewed article  so controversial it was rejected twice by journal reviewers  before “getting in “(pdf here)!  Some background on why this happened is found in a footer way down below….

Its common knowledge today that an aircraft can produce in essence a contrail in clouds at temperatures down to about -10°C and must be avoided when researchers are sampling the same cloud over and over at below freezing temperatures.

Back to the beginning:

The day began well enough with a nice sunrise over the Catalinas:

7:28 AM. Really cold Altocumulus perlucidus lurks over the Catalinas.   The sounding suggests that this layer was at -26̂°C, and yet no ice or virga is present.  This is not unusual.  Ice tends to form more readily when the droplets in clouds are larger–these were likely tiny, 10-15 microns in diameter, and, being a layer high in the atmosphere, not connected to the ground, meant there would be a dearth of ice-forming substances like dirt, well, kaolin mineral particles.
8:01 AM. Well, OK, for the really sharp-eyed cloud maven juniors, yes there was a trace of ice here and there in those clouds.

Here’s the early morning National Weather Service  balloon sounding from the U of AZ:

This sounding was launched about 3:30 AM AST yesterday morning. During the day, the bottom of the Altocumulus clouds lowered and got a little warmer, but still plenty cold for aircraft ice production.

Then, as the Altocumulus layer filled in from the west, the aircraft effects roared to life.  An example from yesterday, one that passed right overhead of little Catalina!

10:01 AM. A parch of aircraft-induced ice in this Altocumulus perlucidus translucidus composed of supercooled droplets otherwise, is about to pass overhead of Catalina.

 

10:08 AM. High temperature contrails rip through a Altocumulus perlucidud translucidus layer up around -25°C.
10:10 AM. Looking for some optical fireworks here, such as a tangential arc (halo curving the wrong way), but only a hint of one showed up. Can you see it?
11:23 AM. Another clearing with ice below it is seen just SW of Catalina from the parking lot of Basha’s where I went to get some cottage cheese.
11:33 AM. Sun dog (parhelia) lights up in the ice patch above after I came out of Basha’s with some cottage cheese.  Note to writers;  little, seemingly irrelevant details like what you bought in a supermarket makes your writing come alive for the reader.
1:21 PM. There’s another couple! They were just everywhere yesterday!
3:52 PM. Later as the moist layer deepened and lowered further, there was ice aplenty, but it was impossible IMO to tell whether it was au natural or aircraft-induced. Surely, some was due to aircraft penetrations of supercooled clouds. However, when the air is rising enough, a hole or ice canal may not appear since droplets can reform rapidly.
3:52 PM. Looking more to the west where the long trails of ice are more visible.
4:14 PM. I feel asserting here. I assert that this one is from an aircraft, but with droplet backfill that prevented a hole from forming.  Looks like “phony” virga to me, and, of course, to you, too, as a certified member of the cloud maven society.
5:21 PM. Interestingly nearly all virga disappeared about this time, certainly nothing extraordinary that led to the suspicion of aircraft induced ice. The sounding suggests that the higher temperatures that the Altocumulus layer was at may have been the reason. See below…
The U of AZ balloon sounding launched at 3:30 PM suggests the bases of the Altocu have dropped down to about 18,000 feet above sea level, 15,000 feet or so above Catalina, and are much warmer, and thicker than when the day started as we could see.

 

 

The weather ahead

More interesting middle and high clouds, probably a great sunset/sunrise or three, but no rain, just virga.  The present mass of middle clouds passing over has some virga and sprinkles, but that’s about it  from this episode.  No real support yet for a change in our dry, warmer than normal weather regime in spaghetti plots though one trough a week or so out is forecast to bring a little rain.

The End


Some background on “APIPs”

This phenomenon had been shot by photographers for decades, yep, DECADES,  BUT, it was believed (apparently) by those doing cloud research, that it only happened at very low temperatures such as those when the normal contrails we see occur (at temperatures lower than -35°C), viz.,  it was ignored.

Another factor was that all of the rare photos of this phenomenon, dubbed “Aircraft Produced Ice Particles” (APIPs, by yours truly, though not the greatest name)  appeared in lay or quasi-lay publications and were likely missed by those with big Ph. Ds. who only read technical journals.  An example of this was on the cover of  the Bulletin of the American Meteorological Society in 1968, a cover shot which drew the greatest amount of reader comments that the journal had ever seen!  They went on for a couple of months, some suggesting that the ice and hole in cloud was due to a meteorite!

Also, it was a rare case indeed when the photographer could report the temperature at which it occurred. 

Gray clouds appear over Catalina, then leave

You have to work with what you have.  Imagine a day without crime, or an exploding balloon,  traffic accident, tax folderol, etc.,  and the television news for that day is cancelled, not worthy of air time, maybe replaced with one of our favorite PBS programs, like, “The Desert Speaks”?

Had a nice lenticular a couple of days ago, in case you missed it.

Wasn’t up much that day; you know, the FLU!  Its out there.
7:54 AM yesterday morning. Stratocumulus cloud tops Samaniego Ridge.  Was actually hoping that the encroaching clouds would be cold enough to form ice even though models said no, tops would be warmer than -10° C  (14°F) or so.  However, in windy situations such as we had atop the Catalina Mountains, clouds like these can leave water in the form of “rime ice” on trees.  How pathetic is that; we can only hope for some mountain sky water1 through riming, not actual precipitation?
8:34 AM. Looks pretty good over there beyond Eagle Crest.   Maybe there will be some ice in this deck after all… Or is that dust under that distant band?
8:45 AM. Wonder if something special is going on over there, maybe I should know about?
8:46 AM. Not much going on directly upwind, though Tucson Mountains obscured in dust. Of course, any cloud band is going to propagate, spread in, from the NW yesterday.
9:49 AM. Looking better. Now, if only some ice would form…
10:01 AM. Almost looks like precip. but its not.  Note clouds still topping Sam Ridge, likely lots of rime icing gong on higher up, toward the middle and top of this shallow layer since the droplets are too small at cloud base to produce riming.  Higher up in the clouds like these, the droplets will reach the size (about about 15 um in diameter) where they are large enough to collide with objects and freeze onto them.
10:01 AM. A closer look at a dust-infused crespucular ray that almost looked like fine precip.
11:56 AM. The Stratocumulus deck is thinning, but an anomalous darkening  has appeared, either due to the shadow of a lenticular cloud or a large space vehicle on top of the lower Stratocu.  Note that the clouds have now lifted above even Ms. Mt. Lemmon.  No more riming to add to our aquifers.  No actual  precip was recorded in the county.
12:38 PM. The clearing side of our little cloud band as it slud by, the complete clearing zone to the right.  Tucson Mountains still mostly obscured in dust, though it really wasn’t that windy here.
1:41 PM. Waiting for the electrician…. If you can find a sunny porch out of the wind, its amazing how pleasant 52°F can be. BTW, if you need an electrician badly, but it conflicts with open heart surgery, its best to cancel the open heart surgery; you may never get another chance to get a licensed, bonded electrician out, but you can always have open heart surgery on another day.  The above, our former home, rented for so long, now in the process of being sold.  (boohoo).

No real change apparent in the drought pattern.

The End