Art Rangno – Page 19

While continuing to look backwards, this:

Kind of an abnormal, pithy, succinct blog today. Average WY precip in Catalina, which I meant to add to this chart, is 16.69 inches, so this past WY was a tad above normal.

The End

Looking back; your updated Catalina water year and summer rainfall graphs

Let’s face it, for most of the people living in Arizona, their best years are in the rear view mirror, as are mine which were probably about 50 years ago… Following that thought, let us not look ahead to further declines, but rather look back at the last water year for Catalina, ending this past September 30th, and see what it says, if anything, about the changing global climate we hear so much about:

Your Catalina water year history, compiled through 2008 by the folks at Our Garden there on Stallion Avenue off of Columbus where great, and fresh organic vegetables can be purchased every Wednesday and Saturday morning. Tell them Art sent you! — Your Catalina water year history, compiled through 2008 by the folks at Our Garden there on N. Stallion Rs. off of Columbus Blvd. where you can find fresh organic vegetables every Wednesday and Saturday morning. Tell them Art sent you! Haha.

Can’t say I see too much going on here in Catalina so far; things seem pretty stable in the precipitation arena for the full water year’s rainfall.

I point out again, with great redundancy since I have pointed this out before, that the Our Garden climate record started just as a monumental change in circulation patterns occurred. Most climate scientists would attribute that to a shift as due to the Pacific Decadal Oscillation, discovered by important scientists I know well, like Mike Wallace¹, of the University of Washington Huskies Atmospheric Sciences Department where I worked for about 30 years, but in airborne studies of clouds.

The PDO shift, if that’s what done it, was a circulation pattern change that brought astoundingly wet conditions to Catalina and the whole Southwest US, wet conditions unlikely to be seen in our remaining lifetimes, which aren’t that much longer anyway.

You may remember that bristle cone pine tree rings in California, analyzed by Haston and Michaelson in 1994, found only one period in the last 600 years (!) that was as wet as the late 1970s into the 1980s there (certainly spilling into AZ).

Remember how the Great Salt Lake was filling up to record levels back in the 1980s?

And any long term resident here, like the ones that I have spoken to, will tell you about the days of yore when the washes around here were running all year.

Well, that wasn’t the norm. sadly. They were just so lucky to have seen that era.

In weather, what goes around, comes around. Count on it happening again at some point in the future IMO. (Some climate changers might disagree with this assertion.)

How about our summer rainfall, June through September. Well, here’s that graph, updated through this past summer! Hope you like it:

Not much going on here, either.

Yesterday’s clouds–another day, another rainbow, of course.

Sprinkles of rain occurred off and on all day yesterday, but couldn’t muster even one hundredth of an inch of rain! With a few exceptions, the clouds producing the rain weren’t too deep, though still icy ones, and pretty high off the ground, mostly above 8,000 to 9.000 feet above us, which doesn’t help.

First, a rainbow shot:

4:20 PM. Maybe, following the example of the University of Hawaii (Rainbow Wahini), the Banner University of Arizona should call themselves the Rainbow Wildcats... — 4:20 PM. Looking north toward the Charouleau Gap (on the right). We have so many rainbows in Arizona, maybe, following the example of the University of Hawaii (Rainbow Wahini), the Banner University of Arizona sports teams should call themselves the “Rainbow Wildcats”…

4:42 PM. Here's a problem for a great shaft of rain, sloping tops of Cumulonimbus clouds. Don't see any shaft here, just rain. When tops slope like this, it indicates the updraft isn't very strong and the ice in the cloud is going to collect little in the way of "supercooled" cloud droplets, that would stick to the ice, eventually making it a graupel or soft hail particle, the kind of thing that our vertical shafts are largely comprised of aloft. Slopey tops mean not a lot of growth of the precip, more "stratiform" like rain with fewer is any pulses of big drops. — 4:42 PM. Here’s a problem for a great shaft of rain, sloping tops of Cumulonimbus clouds. Don’t see any shaft here, just rain. When tops slope like this, it indicates the updraft isn’t very strong and the ice in the cloud is going to collect very little in the way of “supercooled” cloud droplets because the ice that forms is ejecting downstream from where the greatest growth would occur due to collecting cloud droplets, ones that would stick to the ice crystal, eventually making it a graupel or soft hail particle, the kind of thing that our vertical shafts are largely comprised of aloft. Slopey tops mean not a lot of growth of the precip, more “stratiform” like rain with fewer is any pulses of big drops.

5:31 PM. Of course, still another rainbow. Notice how the colors are not as vibrant as some rainbows. This would indicate the concentrations of drops are less, and smaller than in the bright ones. So, not a lotta rain falling over there.

3:50 PM. Now here's a shaft with a real top, a pretty vertical one above it. There were a couple of these. Once again the spaces between the shafts lined up to pass over Catalina, rather than the shafts. The Tortolita Mountains got most of this one. I love these scenes, though, so many times resulting in disappointments. — 3:50 PM. Now here’s a shaft with a real top, a pretty vertical one above it. There were a couple of these. Once again the spaces between the shafts lined up to pass over Catalina, rather than the shafts. The Tortolita Mountains got most of this one. I love these scenes, the backlighting, though, so many times they have resulted in disappointments.

4:01 PM. The "Torts" cleaning up with a decent rain as that complex passed over them. — 4:01 PM. The “Torts” cleaning up with a decent rain as that complex passed over them.

5:19 PM. But even with a rain disappointment, we get to see these scenes here in The Heights over and over, again and again, to add to redundancy, We are so lucky! The cloud line above the mountains would be Stratocumulus.

5:21 PM. Here crepuscular rays of sunlight produced by falling light rain diverge from the sun's position. Light from an "infinite" source is supposed to be parallel at great distances. This seems to prove that our reality, as is sometimes suggested by philosophers, is not what we perceive with our brains, and the sun is much closer to us and much smaller than generally believed by astronomers... — 5:21 PM. Here crepuscular rays of sunlight produced by falling light rain diverge from the sun’s position. Light from an “infinite” source is supposed to be parallel at great distances. This seems to prove that our reality, as is sometimes suggested by philosophers, is not what we perceive with our tiny human brains. These diverging rays demonstrate that the sun is much closer to the earth and much smaller than generally believed by astronomers… The true reality of life and the universe are sometimes right in front of us.

5:37 PM. By this time, the crepuscular rays and the existential questions they raised were gone and reality was back to normal. Here a pretty good Cumulonimbus with a pretty vertical top and big shaft heads in the general direction of Catalina, once again raising hopes for measurable rain. — 5:37 PM. By this time, the crepuscular rays and the existential questions they raised were gone and our perceived reality back to normal. Here a pretty good Cumulonimbus with a pretty vertical top and big shaft heads in the general direction of Catalina, once again raising hopes for measurable rain. Instead, it faded to sprinkles and our total rain from them was only a trace.

The End

—————–

¹Well, actually we said “hi” in the halls once in awhile, I gave a talk in his class once, and, along with a bunch of Atmos Sci faculty, got to watch the 1992 New Year’s Day Rose Bowl mash down of Michigan for the Washington’s 1991 NCAA Division I fubball championship at his house. He also mediated an authorship kerfluffle between Peter Hobbs and me.

Another day, another rainbow, another trace of rain; ho-hum

Kind of getting tired of gorgeous rainbows every day, ones without a lot of rain here in The Heights. But, here they are again:

Upwind Cumulonimbus clouds faded as the trudged toward Catalinaland yesterday, bottoms evaporating, raining out, leaving only a big patch Altostratus cumulonimbogenitus way up (at least ten kft above the ground) there with rain drops just big enough to survive evaporation and reach the ground just before 3 PM.

2:18 PM. Heading for Catalina, right side will maintain--note nice flat base, left side of heaviest shaft is a gonner. No renewing base/updraft. You hope that isn't exactly what's heading for you. — 2:18 PM. Heading for Catalina, right side will maintain–note nice flat base, left side of heaviest shaft is a gonner. So, hope is on the right (not a political statement, but rather referring to the part of the cloud you want to be heading for you, which is not the shaft itself due to the short lifetime of shafts, but the new parts where new shafts will emanate. No renewing base/updraft over there on the left. You hope that segment isn’t exactly heading for you. We shall see in just a few minutes of yesterday time.

2:24 PM. OK, we're done as far as rain goes in Catalina from this. The updraft and solid base are propagating to the right, meaning that nice appearing rainshaft will be what targetis us. But the lives of shafts are so short without renewal, and that renewal is going to slip to the west of us. — 2:24 PM. OK, we’re done as far as rain goes in Catalina from this. The updraft and solid base are propagating to the right, meaning that nice appearing rainshaft will be what targetis us. But the lives of shafts are so short without renewal, and that renewal is going to slip to the west of us. Notice how in six minutes the shaft on the left is almost completely gone.

2:48 PM. Hard to believe that this is all that's left of that pleasant Cumulonimbus cloud, an Altostratus translucidus cumulonimbogenitus , maybe with praecipitatio as well with it. Note the sun is shining through larger ice particles like snowflakes, its disk cannot be made out, though its position can. — 2:48 PM. Hard to believe that this is all that’s left of that pleasant Cumulonimbus cloud, an Altostratus translucidus cumulonimbogenitus , maybe with praecipitatio as well with it since you can see a veil of preicpitation is reaching the ground. Note the sun is shining through larger ice particles like snowflakes, its disk cannot be made out, though its position can. If this cloud was a thin droplet cloud, the sun’s disk could be seen as a sharply outlined disk.

In the meantime, all the excitement, possibly spurred by the gusty outflow winds that accompanied the above seen, was happening almost overhead to the NW-NE, as a great line of Cumulus bases blackened. They were already passed us, but if they unloaded and sent a pulse of wind out and toward us, then we might end up in a wind clash zone, with huge clouds forming overhead. OK, was dreaming again, but here’s what was going on, which ultimately led to another major dump on the CDO watershed.

2:20 PM. Dark Cumulus bases mass over Saddlebrooke and north. No precip trails yet, but they were virtually assured. Started videoing this scene about now.

2:28 PM. In just eight minutes this has become really menacing, possibly a major dump on Saddlebrooke with more golf balls flooding down into the CDO wash as happened the previous day. Now looking for the first strands of the largest hydrometeors (likely hail or graupel) to drop through the updraft, which is looking very substantial at this time due to that well-formed base.

2:30 PM. Here's a close up of that base over Saddlebrooke, now placed in the "Cloud Base Collection" series that we offer readers from time to time. — 2:30 PM. Here’s a close up of that base over Saddlebrooke, now placed in the “Cloud Base Collection” series that we offer to readers from time to time. We’re hoping ot get into a gallery soon.

2:37 PM. "Thar she goes!" This is really hard to see, but at top center the rain/hail/whatever is just starting to show out the bottom. — 2:37 PM. “Thar she goes!” This is really hard to see, but at top center the rain/hail/whatever is just starting to show out the bottom. Some of these, likely gigantic drops, are already reaching the ground. Notice the slight dimming of the Cumulus clouds in the background. That would be the developing rainshaft is going to be.

2:39 PM. Now even little teeny babies can see the shaft dropping out.

2:42 PM. For all to see now.... — 2:42 PM. For all to see now….just three minutes later.

2:44 PM. Just another two minutes later. Its pretty remarkable how fast these things collapse. The whitish strands are likely hail/graupel shafts, often located on the upshear/upwind side of thunderstorms.

2:49 PM. Soon the plop of all that rain push enough air out of the way that the shaft extruded outward toward the west. Note that rain would be falling on people from a raining cloud some mile or three away. The heaviest rain seen in the ALERT gauges from this event was only 0.79 inches at Pig Spring, near the Charouleau Gap. The peak rain was probably in the 1-2 inch range.

Hiked over to see if the Sutherland Wash, east of the similarly named housing development, Sutherland Heights, had a good flow from our “Mighty Kong” of prior day. It had:

3:45 PM. The Sutherland Wash scene showing that it flowed bank-to-bank as did the CDO here in Catalina.

The weather ahead

Seems Remnant Roslyn will spit out another snippet of moisture ahead of our fall-like cold front passage late Sunday or early Monday bringing clouds, and with clouds, a slight chance of measurable rain. Don’t hold your breath for measurable rain IMO. Hope I’m as wrong as the prediction I made to a friend that the Stanford Cardinal would trounce the wildly overrated Washington Huskies fubball team last night.

The End.

Eruption! CDO ran big last night (updated with golf balls shown in the wash))

This just in

Just back from a horsey ride with Zeus the horse. Rode into the CDO to see the surprising view that it had run bank-to-bank last night after that mighty cell passed by along the foothills. In the wash, were golf ball-sized golf balls scattered throughout the wash, indicating that it hit the planned community of Saddlebrooke with it many golf courses very hard. No golfers were found.

The Pima County ALERT gauges really did not call out that such a flow would occur from precip data around here, the greatest amount being barely over an inch, and its likely that such a flow in the CDO, bank to bank would need 2-3 inch dump in its watershed.

This morning around 10 AM in the CDO south of the E Golder Ranch Drive bridge,

———-end of updated material unless I get more updated——

After an afternoon of “steady-state” Cumulus congestus and small Cumulonimbus clouds trailed northward from the Catalina Mountains, the “Mighty Kong” erupted about 5 PM providing one of the most intimidating, yet majestic and beautiful scenes of the summer rain season; this or any.

Cloud Maven Person was indoors drowning his sorrows concerning what appeared to be a a grotesquely failed forecast of a good rain day (“about half an inch”) here in Catalina in flavorful Indian cuisine when the unexpected began to take place outside. So, the photo record is incomplete for this event. “CMP” had given up on the day.

Just measured in NWS-Style 8-inch gauge and CoCoRahs gauge:

0.12 inches was our total here in the Heights.

And, the photos aren’t quite as good as they should be, slightly out of focus since CMP didn’t adjust his camera for the dark scenes his was seeing. Oh, me. Missed the great sunrise, too, due to not having memory stick in the camera! Oh, me.

The day started propitiously enough with a ton of clouds, and a line of weak Cumulonimbus heading for us from the S and SW. A small Cb can be seen on the left. — 6:48 AM. The day started propitiously enough with a ton of clouds, and a line of weak Cumulonimbus heading for us from the SW -W. horizon. A small Cb ahead of this line can be seen on the left.

7:14 AM. Looking at this scene, and pondering a day of these, "CMP" is wondering just how many inches of rain we might have, — 7:14 AM. Looking at this scene, and pondering a day and evening of these, “CMP” is wondering just how many inches of rain we might have,

However this line faded, bringing only sprinkles, a trace of rain to Catalina, and was followed by a huge clearing and sunny skies, thought to be a good thing at the time. Soon, gigantic Cumulonimbus clouds would erupt to over the mountains all quadrants… Nope. By mid-afternoon, only Cumulus congestus had formed with an occasional bit of ice and rain visible, all to the north.

2:08 PM. Cumulus congestus repeatedly formed in the lee of the Catalinas. Occasionally one produced a shower. The clouds are moving from right to left in southerly flow, probably pinching together in the lee of the Catalina Mountain “sky island” as happens in the lee of real islands.

4:21 PM. Another nice Cumulus congestus, but where's are the Cumulonimbus clouds, the big line coming in from the S and SW? Pretty much threw in the towel, gave up except to document for purposes of training a little conversion from water to ice visual lesson in one of these turrets that climbed just high enough to convert. — 4:21 PM. Another nice Cumulus congestus, but where’s are the Cumulonimbus clouds, that big line of them coming in from the S and SW? Pretty much threw in the towel, gave up except to document for purposes of training a little conversion from water to ice visual lesson in one of these turrets that climbed just high enough to convert.

4:25 PM. Thus in a series is just 5 min long. Shows how fast the liquid looking cloud can convert to one that is all ice and droplets evaporate due to incursions of dry air, and their molecules race over to that ice crystal next to them. When water and ice are together, its supersaturated with respect to ice, and water molecules head toward any ice around, accumulating as a solid on the ice (a process called deposition), racing over there as a vapor.

4:27 PM. A very slight change has taken place. The tight cauliflower look due to liquid water “cells” (such as those on the left side where a new turret is rising up) are disappearing, Its not very obvious at all, but you should be thinking even with this little bit of change, “There she goes! It made it to the “glaciation level” today.”

4:28 PM. Underneath this converting turret are ice particles that are just starting to fall out. Can you see the little fibers of ice? Since they don’t have a long water path to fall through, these would be pretty pristine ice, maybe only lightly “rimed” covered in frozen cloud droplets. Notice to here and in the next shot, that they are sloping a bit, indicating they’re not heavy ice particles at all. If you’re really good, you can see that the whole turret has changed, no longer looks “watery”; that tight, hard, cauliflower look has “mellowed”, the crenelations have mostly disappeared. What is a “crenelation” anyway? Better look it up….

4:30 PM. Its a gonner here, no liquid water is left in that turret. The question we still struggle with is how this conversion happens so fast?

This was the last photo I took until walking out of a local Indian restaurant and exclaiming, “What? When did this happen?” It was so clear to the S-W with the exception of a single dissipating Cb that it didn’t even seem worth a photo.

6:04 PM. Hope! — 6:04 PM. Hope for that great, meaningful rain in Catalina, though I am in Rancho Vistoso when shooting this.

6:04 PM. Looking over the Catalina Mountains as much as I could. Look at that nice, solid base!

6:08 PM. Luxurious shafts of rain begin to pour out of solid cloud bases. And look at the one protruding outward toward Rancho V. THis is looking incredible for something humongous to happen. Not sure why this happened? Was there a trigger aloft that was going over this late in the day?

6:11 PM. Now, a rainbow to boot! This shot from Honeybee Canyon Park.

6:13 PM. This is becoming something memorable. Losing control, photos every minute or so, but ISO level too low!

6:14 PM. In the meantime a shelf of clouds, Stratocumulus I'd say, spreads westward from the storm. — 6:14 PM. In the meantime a shelf of clouds, Stratocumulus I’d say, spreads westward from the storm. Would they, could they erupt, too? No, as it turned out.

6:16 PM. As dark fell and the rainbow faded, it was now becoming evident that this late eruption was becoming something special. The rest of the time was spent racing home to be there when it hit Catalina/Sutherland Heights. — 6:16 PM. As darkness fell at Honeybee, and the rainbow faded, it was now becoming evident that this odd late eruption was becoming something special. The rest of the time was spent racing home to be there when it hit Catalina/Sutherland Heights.

6:26 PM. Got this shot waiting at the light at Rancho Vistoso Blvd and Oracle Rd. By this shot, I am thinking, unbelievable what has happened! This has become the "Mighty Kong" of summer storms. — 6:26 PM. Got this kind of crummy shot waiting at the light at Rancho Vistoso Blvd and Oracle Rd. By this shot, I am thinking, unbelievable what has happened! This has become the “Mighty Kong” of summer storms, and its spreading away from the mountains toward Sutherland Heights!

6:33 PM. Car was blasted going down Golder Ranch Drive by not blowing dust but blowing gravel as outflow winds slammed down Golder Ranch Drive. Estimated gusts 60 mph. Afraid to look at front of car this morning. Also look at how firm, solid that leading base is, telling you that there is a strong updraft feeding into it. More cells will develop downwind. That's Jenny and Matt's house shining in the sun on the hillside. — 6:33 PM. Car was blasted going down Golder Ranch Drive by not blowing dust but blowing gravel as outflow winds slammed down Golder Ranch Drive. Estimated gusts 60 mph. Afraid to look at front of car this morning. Also look at how firm, solid that leading base is, telling you that there is a strong updraft feeding into it. More cells will develop downwind. That’s Jenny and Matt’s house shining in the sun on the hillside.

6:33 PM. Looking from Golder Ranch Drive toward Samaniego Ridge, obscured in rain.

Well, as it turned out it was a near hit, only 0.06 inches fell in a violent few minutes of huge drops at my place in Sutherland Heights. From what I saw going by, and needing 0.44 inches on yesterday morning’s forecast of 0.50 inches in Sutherland Heights. about 500 yards farther west for this remarkable, dramatic storm would have given us that amount easily. 1.06 inches was recorded at Cargodera Canyon, NE corner of Cat State Park, and several sites in the foot hills of Catalina toward the mountains area had more than half an inch.

A quickie take on a U of AZ model run from last evening’s global data, has Cumulonimbus clouds developing to our southwest and rolling across Catalina in the afternoon. This would be, appropriately, considering the definition of the end of our summer rain season as September 30th, very appropriate.

The End.

Rainbows and sunsets; also, fall weather coming in October!

Should be some good rain today in Catalina, FINALLY! Thinking maybe half an inch or so over the next 24 h, something decent, as tropical air drains o northward and over us out of tropical storm remnant, Roslyn (“Rozzi”).

Clouds and weather interruption:

Due to the name of our weather-affecting tropical storm, Roslyn, I am now reminded of a profound, life-altering “Hallmarky” chapter of life when I was in HS, involving another Roslyn (aka, “Rozzi”). In an another attempt to increase blog readers, those really not interested in clouds and weather anyway, I have inserted this story about a 15-year old, shy boy and his incapacitating crush on a Rozzi R as a junior in HS I suspect it is a fairly common one in some ways, although this one leads to the formation of other people with a different classmate. The Story of Rozzi R

This story was passed to Rozzi, who had no idea who I was, only in 2009, btw. She seemed to like it, and told me about her life, family and three kids. I think its OK to share it.

——————————

Back to weather, at 7:11 AM, one pulse of rain is within a half an hour or so. (Later, we only got sprinkles out of that first pulse).

Yesterday’s clouds

Nice rainbow last evening; nice sunset, too:

6:26 PM. Altocumulus and patches of a higher mostly ice cloud (Cirrus spissatus or Alstratus?) provided quite a nice sunset yesterday evening. Back the other way, were rainbows galore.

6:11 PM. Rainbow under a more or less stratiform remnant of a Cumulonimbus cloud.

The Prodigal Storm yesterday afternoon

Yesterday afternoon had quite the dump and something of a little ‘boob from the outflow winds, so much rain came down initially around Oro Valley/Marana, west Tucson, south of Pusch Ridge. Was heading this way, too, with nice big, black, solid-looking base. Started a video of it, thinking about the gush was to strike Sutherland Heights/Catalina.

Here it is, in all of its glory and subsequent dissipation:

3:09 PM. Outflow from TUS storm builds ledge of Cumulus base S-SW of Pusch Ridge.

3:20 PM. Only 11 minutes later that new base has unloaded its load on Oro Valley. ).59 inches at the CDO and Ina Road intersection yesterday, but likely an inch fell out of this in the peak rain area. Note how the winds are pushing rain and dust west and northwest.

3:25 PM. She'll be comin' around the mountain when she comes. This was looking so good for us. Why? Look at that great SOLID base coming at us ahead of the rain! — 3:25 PM. She’ll be comin’ around the mountain when she comes. This was looking so good for us. Why? Look at that great SOLID base coming at us ahead of the rain! The lower scruffs of cloud are called “pannus” and in this case they are created by the nose of the outlfowing winds from this storm. What you want is for those outlfowing winds to keep generating new, fresh Cumulus bases, ones that explode upward into Cumulonimbus clouds. Without the new, good base and the updraft that goes with it, all of the rain can fallout in less than half an hour from the ones already raining. Its a supply thing, you have to keep it going. What if there were no new people born? Well, after awhile the supply of people would run out.

3:31 PM. By this time, you're getting worried about this incoming system. Look what's happening to the formerly solid base. Its beginning to get "lumpy" looking with dark and lighter spots telling you the updraft is getting broken up, fallling apart, maybe due to the blockage presented by Pusch Ridge. — 3:31 PM. By this time, you’re getting worried about this incoming system. Look what’s happening to the formerly solid base. Its beginning to get “lumpy” looking with dark and lighter spots telling you the updraft is getting broken up, fallling apart, maybe due to the blockage presented by Pusch Ridge. But there’s still hope, the updraft MIGHT reassemble itself….and there are still a couple of pretty good base “hot spots” where the updraft is still good.

3:37 PM. "Its is finished." — 3:37 PM. “Its is finished.” What;s heading toward Catalina is that transparent veil of rain on the left of the shaft. We now have no chance for a major dump. Maybe it will measure though, a few hundredths…

3:44 PM. Need more be said? Sprinkles occurred here, did not measure. Warning: A sprinkle isn't drizzle, a continuing theme here. — 3:44 PM. Need more be said? Sprinkles occurred here, it did not measure. Warning: A sprinkle isn’t drizzle, a continuing theme here. Look at the “crapulent” bases now! Oh, me. I wanted to go in the house and never come out again, it was SO DEPRESSING to see this happen. Lots of storms make it past Pusch Ridge, too, but not this faker.

3:44 PM. As usual, major shafting occurred AROUND Catalina, and not on it, pretty much like this whole summer has been. This is looking north toward Bio2

5:16 PM. Nice interplay of rain and sun.

Models, with spaghetti support, show a strong, but dry, cold front coming through next week, and fall will be in the air as nighttime lows drop into the 40s in our colder, lower spots, like at the bottom of Catalina State Park, in the CDO wash, etc.

The End.

Model predicted hurricane not passing over Tucson today

Catalinans were warned from this very blog weeks ago that a hurricane would definitely not pass over Tucson today, though our best model showed that happening.

Let us reprise that computer model prediction of a hurricane over Tucson and how wrong it was:

Valid at 5 PM today! Hurricane center is over Tucson (see arrow if you are unfamiliar with the United States and Arizona.)

———————

Nice weather we’re having today, overcast Altostratus opacus (for the most part; sun’s exact position not detectable) with embedded lenticular clouds, ones located to the WEST of the Catalinas, an unusual sight. Also, there are sprinkles-its-not-drizzle-dammitall falling from this layer all around us. We are currently in a “rain shadow” because of easterly flow aloft that had brought downslope drying to Catalina.

Those poor drops falling from that middle cloud layer of Altostratus (base estimated at 10,000 feet above the ground here at 9;26 AM AST) have almost no chance of reaching us until the wind weakens up there and/or changes direction, or the precip on the way down gets much heavier.

Here’s an example of our rain shadow as of 0900 AST this morning:

I could post the images of this scene I’ve already taken today. But that would be wrong. This is not a “timely” websight/blog, but rather one that discusses the past.

The End

A rare day, a rare “bird”; a day in which rain only due to the collision-with-coalescence process operateddeveloped; hold the ice

Yesterday was as rare a day in Catalina, Arizona as seeing the marbled murrelet in Olympia, Washington.¹

Why?

Our bit of rain (0.12 inches in Sutherland Heights) was only due to that formed by the collision-coalesence process, some times called the “warm rain” process, or more technically, non-brightband rain².

No ice needed.

Usually clouds at inland locations like Arizona have so many droplets in them , a few hundred thousand per liter or more, larger drops that can collide and coalesce don’t form because the condensed water is spread over so many of them.

So I could feel the excitement out there as that frontal band got closer. Perhaps you saw the drizzle-mist rainbow on the Tortalitas, looked at cloud tops, and saw no ice. If you said you saw some ice yesterday you were mistaken or lying to impress your friends.

Let us review yesterday in clouds:

7:36 AM. Looking toward the Tortolitas at the line of Cumulus congestus approaching Catalina. Can you see the little piece of rainbow just below those low,low cloud bases? Cloud bases were hot yesterday, 15-17° C, and thus our clouds were extra loaded with water. The warmer the base, the greater the amount of water that condenses above cloud base. The usual cloud base is around 5-10° C this time of year. Photo, of course, not taken while driving; that would be crazy. Is just "shopped" to look that way to provide an "action" setting. — 7:36 AM. Looking toward the Tortolitas at the line of Cumulus congestus approaching Catalina. Can you see the little piece of rainbow just below those low,low cloud bases? Go straight above the white dot marker in the road (Oracle). Cloud bases were usually hot yesterday morning, 15-17° C, and, thus. our clouds were loaded with extra water. The warmer the base, the greater the amount of water that condenses above cloud base. That means drops is bigger, and can reach sizes where bumping together leads to sticking, not rebound as is normal. The usual cloud base is around 5-10° C this time of year. Photo, of course, not taken while driving; that would be crazy. Is just “shopped” to look that way to provide an “action” setting.

7:40 AM. Such a pretty scene! Can you see the little bit of lower hanging cloud below the line of Cumulus? It looked like our windshift, cold front line might be on the doorstep. Waited until afternoon to get here, though.

7:45 AM. Here’s a closer look at those lower windshift indicating clouds to the NW yesterday. Now you KNOW the front and “FROPA” is getting close. Very exciting scene. But would it rain? No ice was visible anywhere around.

7:44 AM. In the meantime, Stratocumulus clouds gathered upwind of Catalina with light rain visible just above the horizon SW/ Was looking for an icy top. to extrude above the Stratocu, but didn’t see one. You didn’t either.

7:49 AM. In the meantime, not much is going on over the Catalinas. Notice how much shallower the Stratocu are than just over there by the Tortollitas. Really showed that the lifting zone of the front was so close!

8:22 AM. Suddenly, it was raining! All this misty rain having developed while the author wasn't paying attention. Did that Stratocumulus develop rain, or did that bit of rain above the horizon move in? Maybe this can be answered at the next club meeting. — 8:22 AM. Suddenly, it was raining! If you don;t believe me there are drops on the camera lens in this photo. All this misty rain developed while the author, cloud maven person, wasn’t paying attention. Did that Stratocumulus develop rain, or did that bit of rain above the horizon move in? Maybe this can be answered at the next club meeting.

8:25 AM. Starting to lose photo control here, as things closed in, prettyness getting enhanced be passing rays of sun on the greenish Catalina Mountains. How can you not record this? Well, maybe you can go ho-hum, but no cloudcentric person could.

8:33 AM. By this time it was all over and 0.05 inches had been logged. Here, those raining clouds zip off to Oracle State Park and vicinity over the horizon. Still looking for icy tops, but haven't seen any, such as in those Cumulus tops, horizon left. — 8:33 AM. By this time it was all over and 0.05 inches had been logged. Here, those raining clouds zip off to Oracle State Park and vicinity over the horizon. Still looking for icy tops, but haven’t seen any, such as in those Cumulus tops, horizon left. Photos now being taken almost every minute, certainly within every five minutes. Wondering if I need a doctor….?

8:47 AM. Rain begins to form on Pusch Ridge from low-based Cumulus clouds. The misty look, lack of a shaft, has you thinking "warm rain" all the way, Maybe of Hawaii, too. — 8:47 AM. Rain begins to form on Pusch Ridge from low-based Cumulus clouds. The misty look, lack of a shaft, has you thinking “warm rain” all the way, Maybe of Hawaii, too.

Skipping a LOT of pretty scenes now…..

9:47 AM. Think how special you would think you were when this ray of sunlight bathed you for those few seconds, darkness all around.

9:48 AM. Pretty much the same scenes as you've already seen over and over again, but this one has a bird in it for the sake of variety. — 9:48 AM. Pretty much the same scenes as you’ve already seen over and over again, but this one has a bird in it for the sake of variety.

10:33 AM. A little break allowed some nice scenes of the Cumulus congestus on the Catalinas. Notice how low the base is. You could have been hiking in it. Very few people get to hike in the base of a Cumulus congestus cloud. You still haven't seen any sign of ice, either. — 10:33 AM. A little break allowed some nice scenes of the Cumulus congestus on the Catalinas. Notice how low the base is. You could have been hiking in congestus bases yesterday! Very few people get to hike in the base of a Cumulus congestus clouds. You still haven’t seen any sign of ice, either.

10:44 AM. Something in the way of a shaft out there over Marana/Oro Valley probably made you start to wonder, "maybe there is some ice up there?" It dissipated quickly before it arrived dropping only a few drops. — 10:44 AM. Something in the way of a shaft out there over Marana/Oro Valley probably made you start to wonder, “maybe there is some ice up there?” It dissipated quickly before it arrived dropping only a few drops. Still has hard as you and I looked, we couldn’t see any as it came and its remains went. U of AZ computer model soundings at this time had the tops way above freezing. In case you don’t believe me again here is a sample:

Valid for 10 AM, yesterday. Output was from the 11 PM AST model run, a diagram with a lot of writing on it.

11:50 AM. Major windshift line now beginning to make progress toward Catalina along with a line of deeper clouds along it. Was thinking ice might be seen somehwere up there at this time, but nope. — 11:50 AM. Major windshift line and fontral passage (FROPA) now beginning to make progress toward Catalina along with a line of deeper clouds along it. Was thinking ice might be seen somehwere up there at this time, but nope.

11:52 AM. When looking for ice, you want to look at what’s ejecting from the tops of the clouds. Here, that little flat cloud above the Cumulus clouds is the “ejecta” from those showers just starting to hit the Tortolita Mountains. As you can see as a cloud maven person, it does not have a fibrous look, nor are there fine strands of ice dropping from it, as would be the case if ice was present. SO it was another piece of circumstantial evidence that ice was not involved in even those dark clouds toward the Tortolitas, ones that would eventually give us our final bit of rain here in Sutherland Heights, Catalian. This kind of cloud has sometimes been called a “water anvil.” This was a really exciting moment, though most folks would find that hard to fathom.

12 Noon. A hard shower has popped up over there toward Marana. Now here's I would have guessed these must be some ice at cloud top from the narrowness of the shaft indicating a higher cloud top than in the other nearby shower-producing clouds. Does anyone out there have an aircraft and can fly IFR? It would be great to be on standby like days like this and go take a look at cloud top heights. — 12 Noon. A hard shower has popped up over there toward Marana. Now here’s I would have guessed these must be some ice at cloud top from the narrowness of the shaft indicating a higher cloud top than in the other nearby shower-producing clouds. Does anyone out there have an aircraft and can fly IFR? It would be great to be on standby like days like this and go take a look at cloud top heights.

12:38 PM. Stratocumulus, in one of its best presentations. The rest of the day was overcast, cool with a period of light rain around 2 PM, with the temperature dropping to a remarkable 58° F here in Catalina. Our final rain total was a respectable 0.12 inches. — 12:38 PM. Stratocumulus, in one of its better presentations; lumpy and widespread.

The rest of the day was overcast, cool with a period of light rain around 2 PM, with the temperature dropping to a remarkable 58° F here in Catalina.

The last TUS sounding seemed to confirm this unusual rain day, indicating that the stratiform tops near and over the site were at 0° C.

Here’s pretty much what the balloon went up through: The TUS rawinsonde, launched around 3:30 PM yesterday. Cloud tops would be where the two lines, temperature and dewpoint temperature, separate.

4:04 PM. Looking toward Pusch Ridge and Tucson.

Our final rain total in Sutherland Heights was a respectable 0.12 inches from a rarely observed event. 0.47 inches fell on Ms. Lemmon for the highest amount around.

Might add more later, but am quitting now to go “lunge” and ride a horse..

PS: I have added more, re-written some not so great “formulations”…

The End

1If upon reading that sentence you would like bail on reading about clouds and rain here in Arizona and read about that bird, please consult:

Rare Bird: In search of the marbled murrelet

²When steady rain is occurring, returns have a bright band, or a augmented return from the layer in the atmosphere where snow is melting into rain. On days like yesterday, throughout the Tropics, along the West Coast, among many places, non-brightband rain is fairly common. Typically it falls from clouds with tops warmer than -5° C. Ice usually onsets at temperatures between -5° and -10° C in such clouds. Hawaii is a good example where “warm rain” produces most of the prodigious rain totals there on the windward slopes, such as that at Mt Waialeale on the Island of Kuwai where the average rainfall is more than 450 inches!

A pretty day with some Altocumulus clouds and an icy mystery which isn’t really explained here

Wonder if you saw it, this cloud mystery? First the pretty and the plain:

2:53 PM. A nice example of Altocumulus perlucidus (flakes close together mostly). Hold the ice. How high up above you did you estimate this cloud is? I will estimate, before looking at the TUS sounding, — 2:53 PM. A nice example of Altocumulus perlucidus (flakes close together mostly) transcudius (no gray shading to speak of), hold the ice. No ice was showing here in these clouds. How high up above you did you estimate this cloud is? I will estimate, before looking at the TUS sounding. I am going to guess 16,000 feet¹, meaning about 19, 000¹ feet above sea level. If I am very close I will let you know, maybe spike a fubball.

Ann 2 2016091600Z_SKEWT_KTUS — The Tucson sounding, now launched from the Banner University of Arizona Wildcats around 3:30 PM AST, so its pretty close to the time of the Altocumulus layer. As you can it was at a height. (This being the political season, I am trying to obfuscate error, it was a little higher than I estimated, dammitall. Need more practice. Notice by having text below the arrow, it gives the impresseion of the cloud being lower than it really was. This is kind of a teaching moment in case you run for political office, or just like to play down your daily errorful ways. As meteorologists, we learn this early in our careers because there are so many, its overwhelming, really. (The Ac layer was at 25, 610 feet and at -22° C!!) Cloud maven person, if that’s what he really is, was off by a whopping 6,000 plus feet! Egad! And this height is higher than we really think of where Altocumulus layers inhabit, 22,000 feet above us yesterday. Kind of embarrassing. Humiliating, really². The only consolation I can think of is that other cloud estimators probably would have used a standard number, maybe “12,000¹ scattered.”

Now for that icy mystery yesterday afternoon:

3:54 PM. An icy conundrumdrum-dee dum. Why there?

Let us zoom in some more, see if we can find out something:

3:52 PM. Zoomed view of one of the little anomalous snowstorms going on at 25, 600 feet yesterday. If you click on this, you’ll see the tiny, delicate trails of ice falling out, ones that reflect a different set of circumstances for ice formation and growth that were present in that little cloud, seemingly so uniform, but not really if you were to fly through it with cloud instruments.

However, we have really learned nothing about why SO MUCH ice fell out of a couple of those clouds.

CMP will offer a hypothesis, one that cannot be verified and so he can’t be shown to be in error again:

I think this may have been due to an aircraft passage in that layer, probably more than an hour ago. Hypothesizing, it passed through some of the cloudlets and iced them up real good (that is caused ice to form due to its passage through it, not icing on the wings kind of thing, though that may be a part of the reason ice crystals form. We’re not really sure what causes an aircraft to produce icy holes in clouds or ice canals.

However, in the longer term when an aircraft causes a hole or ice canal, if the layer is sliding upward, the hole or canal fills back in with droplet clouds just like the one an aircraft glaciated. Takes a lot of time for that to happen, at least an hour since the upward slide in mid-level clouds is slight.

Another possible explanation to cover more bases, is that a very few of these now flat clouds once had turrets that stuck up to lower temperatures. Only slightly cooler temperatures from -22 °C might have triggered what was clearly an explosion of ice. But given the stable layer at the top of these clouds, that seems a less likely possibility to me.

3:55 PM. There was one more bit of ice falling out of one of these flakes. Look how tiny that strand is falling from a tiny flake! Remarkable. Since ice nuclei increase exponentially with lower temperatures, maybe a half a degree cooler Celsius at the tippy top of this flake compared with surrounding flakes triggered a few ice crystals.

Another thing we have learned today among the things we have not learned, is that clouds, especially mid-level ones, can be damn cold without having any ice falling out of them, and that ice falling out of them might even be an inexplicable anomaly! Doesn’t really happen with clouds in the “boundary layer”, that is clouds formed from ground heating, and/or connected to dirt and stuff through turbulence. Too many chances for ice nuclei to get in them and most are dirt particles like kaolinite.

The End.

———————————————

¹When you’re speaking to friends, and to sound more pilot-like, more accurate in your cloud height assessments, its best if you say heights as at, “one-six thousand, one-niner thousand, two-five thousand”, etc. As in, “I think those Altocumulus clouds are at one-eight thousand” as an example.

I really think if you talk like that to your friends when discussing cloud heights you’ll see a little bump of credibility for you.

²Its really OK to admit error, to be humbled once in awhile, get your feet back on the ground, not think of yourself as something special like you do. In this regard, I have linked to an exemplary example of a media weather forecaster that was acknowledged a major error in a prior temperature forecast for SEA, but at the same time called out the correct elements of his/her forecast to blunt the fallout from the temperature error. Perhaps, realizing, too, that he/she/transginger, was using too fine a forecast “brush”, learns from that and ends with a broader one: An errorful forecast acknowledged:

An unbelievably long blog about a surprise afternoon sprinkle of rain

A very few small, isolated drops fell between 4:50 and 5 PM here in Sutherland Heights from what appeared to be nothing overhead. You’d have to be really good to have not been driving, and to have anticipated the possibility (by recognizing ice in upwind clouds) and then having observed it. You would be recognized, given some extra adulation, at the next cloud maven junior meeting if you did observe it, that’s for sure.

So, a long blog about anticipating and observing a sprinkle of rain (RW—, “RW triple minus” in casual weatherspeak or text).

We start with some nice, but inapplicable to our main story photos from yesterday.

3:14 PM. Another one of those, to me, memorable, dramatic shots just because of cloud shadows on our pretty mountains caused by Cumulus humilis and mediocris clouds; Cirrus uncinus on top.

3:15 PM. Pretty CIrrus uncinus, "Angel's hair." — 3:15 PM. Pretty CIrrus uncinus, “Angel’s hair.”

3:15 PM. Looks like a cloud street off the Tucson Mountains, one that streamed toward Catalina. Hope you were unbusy enough to notice it. Its a pretty common one here when the lower level winds are out of the SSW, and the clouds shallow. — 3:15 PM. Looks like a cloud street off the Tucson Mountains, one that streamed toward Catalina. Hope you were “unbusy” enough to notice it. Its a pretty common one here when the lower level winds are out of the SSW, and the clouds shallow.

3:50 PM. Shadow quirk. The cloud shadow follows the terrain line. Wow. Never seen that before, but I suppose if you had an infinite number of monkeys watching, they'd see it all the time. Maybe they would type out some Shakespeare as well in time. — 3:50 PM. Shadow quirk. The cloud shadow follows the terrain line. Wow. Never seen that before, but I suppose if you had an infinite number of monkeys watching, they’d something like this all the time. Maybe they’d type out some Shakespeare as well in time.

3:54 PM. While busy watching the cloud-sahdow dappled mountains, some honest-to-goodness Cumulus congestus arose in a line to the southwest! Not at all expected! Looks like they're tall enough to form ice, but don't see any. Will take too many photos to see if any develops though. — 3:54 PM. While busy watching the cloud-sahdow dappled mountains, some honest-to-goodness Cumulus congestus arose in a line to the southwest! Not at all expected! Looks like they’re tall enough to form ice, but don’t see any. Will take too many photos to see if any develops though.

3:56 PM. That poor turret that first extruded from this line (center raggedy one) is being ravaged by "entrainment", that cloud killing process wherein the surrounding dry air gets in and kills off the droplets. Pretty sad when you think about. It also shows you just how friggin' dry the air was just above the main tops. No ice visible here. — 3:56 PM. That poor turret that first extruded from this line (center raggedy one) is being ravaged by “entrainment”, that cloud killing process wherein the surrounding dry air gets in and kills off the droplets. Pretty sad when you think about. It also shows you just how friggin’ dry the air was just above the main tops. No ice visible here.

3:56 PM. Let's zoom in to be sure. Anyone saying they can see some ice in this is either an ice-detecting genius or just play lying. — 3:56 PM. Let’s zoom in to be sure. Anyone saying they can see some ice in this is either an ice-detecting genius or just plain lying. BTW, that turret on the left, partially visible, is much taller, so its got a good chance to convert to ice.

3:58 PM. Now even little tiny babies can see the ice that formed in that now dessicated turret. This means some rain fell out of it! Wow, did not see that coming today. — 3:58 PM. Now even little tiny babies can see the ice that formed in that now dessicated turret. This means some rain fell out of it! Wow, did not see that happening today.

3:58 PM. Pulling back to grab the whole scene, those Cumulus congestus clouds converting to small Cumulonimbus clouds that will bring those few tiny drops to Catalina in an hour. — 3:58 PM. Pulling back to grab the whole scene, those Cumulus congestus clouds converting to small Cumulonimbus clouds that will bring those few tiny drops to Catalina in an hour even as the dry air up there wasted them. Real cloud mavens would be thinking about the possibility of rain here, seeing the ice form in clouds upwind of us, that right at that time! Congratulations!

4:09 PM. Doesn't look that great now, but areas of ice visible, and its heading this way with a light shower falling out of it! Maybe we'll pick up another trace! — 4:09 PM. Doesn’t look that great now, but areas of ice visible, and its heading this way with a light shower falling out of it! Maybe we’ll pick up another trace! But what cloud name would you put on this scene? Well, its kind of embarrassing to call them “Cumulonimbus”, but we do have a suitable moniker for weakly-producing Cumulus ice clouds with a little precip, Cumulus congestus praecipitatio. Yep, that’s the name I would use here since the rain is reaching the ground (is not just producing virga).

4:30 PM. Code 1 rain shaft, a transparent one. We're going to a LOT of trouble for a trace of rain here! But, you should have been really excited by this time. The possiblity of rain is just minutes away, but you'll have to be outside to notice it! — 4:30 PM. Code 1 rain shaft, a transparent one. We’re going to a LOT of trouble for a trace of rain here! But, you should have been really excited by this time. The possiblity of rain is just minutes away, but you’ll have to be outside to notice it!

4:40 PM. Drawing back to look at the whole scene, which is not that great. Bottom of sprinkle cloud has evaporated leaving that big patch of ice, left side of photo. Can the sprinkle heading toward us survive? Your heart probably was really pounding at this point since you wanted to see some drops so BAD, report that trace the next day, one that maybe only you would have noticed.

4:47 PM. Three minutes to first drops, though here no drops would be reaching the ground from the condition the cloud is in now, its too high, just really anvil ice, and the ice crystals too small, The drops that are going to be intercepted are surely the last ones reaching the ground, the top of the sprinkle shaft, above which there are no more drops.

4:55 PM. Drops are collecting on the windshield a few hundred yards from the house with almost no cloud aloft at this point! A trace of rain has been logged!

The End

(What about those gorgeous Cumulus congestus and Cumulonimbus calvus clouds over toward and well beyond Charouleau Gap about this time? Maybe later or tomorrow.)

A thunderful day brings a little rain to Catalina, drenches the Tortolita Mountains.

The day started with some nice Altocumulus “pancakus”, some lenticulars and breezy conditions, reminding one of fall day with a cold front approaching. Small Cumulus appeared quickly, but with the wind, you wondered if they would get enough heating to power upward into Cumulonimbus clouds.

By noon you had your answer as a large Cumulonimbus complex settled in just beyond the Tortolita Mountains west of Catalina. And it pretty much recurred there and over the Tortolitas all afternoon. In the meantime, passing light showers dotted this side of the Catalinas, but that was about it. No “Code 4” shafts on those mountains yesterday. Rain totals were less than a half inch, and most less than a third. On the other hand, would guess that parts of the Torts got well over an inch. The cores missed us again, with Sutherland Heights logging only 0.03 inches.

Developing showers passed over Catalina dropping occasional very large, sparse drops, but shafts generally fell out of those clouds after they had passed off to the northeast.

Late in the afternoon, the line of recurring showers finally approached Catalina, but as dry air encroached in the middle levels, at the same time, catching up to that standing line, all those great mushrooming clouds were no more. The cloud story board is below:

Yesterday’s Clouds but Yesterday’s Gone

(by Chad and Jeremy but with photos of Peter and Gordon with whom the former were often confused with, the site notes! How funny is that?)

Oh, well, yesterday might well have been the end of the summer rain season here in Catalina as far as rain goes, so an ending point song seemed appropriate.

6:16 AM. Altocumulus with a underlying Altocumulus castellanus.

6:16 AM. Another view of Altocumulus with an underlying line of Altocumulus castellanus.

8:06 AM. Altocumulus perlucidus translucidus (real thin).

10:55 AM. Altocumulus lenticularis clouds provide the real look of a fall day with a significant jet stream overhead. Cumulus begin to form on the Tucson Mountains in the distance.

12:56 PM. The idea of a fall day is quickly dispelled by the rapid growth of a narrow Cumulonimbus calvus cloud.

12:57 PM. Wow. At the same time, there’s been an explosion of Cumulonimbus clouds to the west through northwest of Catalina. This looked REALLY promising for a dump here, since it would surely expand southward (to the left) from the rain shafts in progress.

1:30 PM. Line of thunderstorms reaches the Tortolita Mountains. This is looking extremely good for Catalina though the thunderstorm is moving left to right rapidly, not toward us. Why does it look good for Catalina? Because you expect winds pushed away by all that falling rain to blow back against the sotuhwest winds and generate new Cu congestus and Cumulonimbus clouds upwind of the shafts, and more in line with Catalina. Summary: it didn't happen though there were numerous times it looked like it was verging on doing this. So, all those thoughts you had out there that this was going to happen were in considerable error. — 1:30 PM. Line of thunderstorms reaches the Tortolita Mountains. This is looking extremely good for Catalina though the thunderstorm is moving left to right rapidly, not toward us. Why does it look good for Catalina? Because you expect winds pushed away by all that falling rain to blow back against the sotuhwest winds and generate new Cu congestus and Cumulonimbus clouds upwind of the shafts, and more in line with Catalina. Summary: it didn’t happen though there were numerous times it looked like it was verging on doing this. So, all those thoughts you had out there that this was going to happen were in considerable error. This was probably because the southwest wind against which the outflow was clashing, was too strong yesterday, limiting how far upwind new clouds could develop.

1:34 PM. This was looking so great! Bases massing there on the right side, pretty much upwind of Catalina.

1:43 PM. Tortolitas now submerged in water. — 1:43 PM. Tortalitas now obscured by water.

1:49 PM. Showers are developing farther upwind of the main blast over the Tortolitas as expected and near to upstream of Catalina! Gloating here. Was SURE now we'd get a tankful of rain within the hour. — 1:49 PM. Showers are developing farther upwind of the main blast over the Tortolitas as expected and near to upstream of Catalina! Gloating here. Was SURE now we’d get a tankful of rain within the hour.

1:53 PM. In only a few minutes its looking so much better for us, and these showers are racing at us. Looks like the whole line is drifting east, too. — 1:53 PM. In only a few minutes its looking so much better for us, and those showers and thunderstorms are racing this way! Looks like the whole line is drifting east, too. In the meantime, the thunderstorms moving away from the Tortolitas and toward Saddlebrooke Ranch and points north have sent out a blast of northerly winds into Sutherland Heights, pretty much like yesterday. The clouds overhead begin to respond to that uplift caused by this blast of north winds.

2:16 PM. First nice cloud base waits until passing by to drop load, but another promising one appears upwind! — 2:16 PM. That first nice cloud base waited until passing by to drop its load, but another promising one appeared upwind!

2:17 PM. In the meantime, another ferocious thunderstorm is dumping on the same area of the Tortolitas as the prior ones!

2:21 PM. A closer look at the Tortolita blast. Expect wind from this to reach Catalina.

2:22 PM. WIth the north wind blowing you're looking for something to erupt upwind of us as the nose of that north wind pushes into Oro Valley. But here you see that the organization of the cloud bases is poor, too many little light and dark areas, no broad base indicating a strong updraft. This was a depressing shot. — 2:22 PM. WIth the north wind blowing you’re looking for something to erupt upwind of us as the nose of that north wind pushes into Oro Valley. But here you see that the organization of the cloud bases is poor, too many little light and dark areas, no broad base indicating a strong updraft. This was a depressing shot but I took it anyway.

2:27 PM, The severe thunderstorm over the Tortalitas has moved NE. Here you see the kind of cloud base you want to see just upwind of you, not that mess in the previous photo.

2:29 PM. Only a few minutes later, but look at the change that has occurred upwind of us! That north wind scooting down into Oro Valley has finally triggered a massive base just upwind of us We are going to get pounded!

2:33 PM. But that great cloud base moves to the west of us, adajacent to yet another blast on the Torts. Ugh. Just can't get this right. — 2:33 PM. But that great cloud base moves to the west of us, adajacent to yet another blast on the Torts. Ugh. Just can’t get this right.

2:36 PM. Some lightning for you in case you don't believe me that these were thunderstorms. — 2:36 PM. Some lightning for you in case you don’t believe me that these were thunderstorms.

2:49 PM. Yet another promising base, more in the upwind direction passed over, only to leave some enormous drops. Compare splash marks to that mesquite pod on the sidewalk. Sounded like hail at first. But the main load fell downwind. I thought we were going to really get shafted right then, too. Not. — 2:49 PM. Yet another promising base, more in the upwind direction passed over, only to leave some enormous drops. Compare splash marks to that mesquite pod on the sidewalk. Sounded like hail at first.
But the main load fell downwind. I thought we were going to really get shafted right then, too. Not.

3:03 PM. An example of poor cloud base structure upwind of us.

3:04 PM. Curtains of heavy showers continue to bombard the Tortolitas, Amazing how many cells passed through that area as this zone of converging winds remained stationary instead of advancing toward us as I believed it would.

3:18 PM. As skies cleared overhead, some of the prettiest scenes of the day were of these brilliantly white Cumulus congestus clouds over the Catalinas.

3:20 PM. Ice detection drill... Can you tell that those two turrets in the last photos are now mostly ice? — 3:20 PM. Ice detection drill… Can you tell that those two turrets in the last photos are now mostly ice?

3:28 PM. Can a scene be more beautiful? The turret on the far left has converted to ice.

3:29 PM. A single strand of hail or the largest drops have plummeted out of this base. This suggests that they were either very large particles, or that the updraft had a minute weakness that allowed some of the load aloft to escape in something of a narrow chute. And, of course, its part of the line still pounding the Tortolitas!

3:47 PM. FINALLY the line appears to be shifting east toward Catalina, but the tops aren't as high, there are no giant cells any more, an indicating that both drier air is moving in and that the instabliity aloft is changing to less favorable for large storms. Oh, me. This was a discouraging scene. — 3:47 PM. FINALLY the line appears to be shifting east toward Catalina, but the tops aren’t as high, there are no giant cells any more, an indicating that both drier air is moving in and that the instability aloft is changing to less favorable for large storms. Oh, me. This was a discouraging scene.

3:55 PM. While not as heavy as prior showers, there is still hope that the line will produce measurable rain in Catalina as it drifts east.

4:05 PM. By this time, its looking like the slowly advancing line will die before it gets here.

The End, whew.