Yesterday was as rare a day in Catalina, Arizona as seeing the marbled murrelet in Olympia, Washington.1
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:
Skipping a LOT of pretty scenes now…..
Valid for 10 AM, yesterday. Output was from the 11 PM AST model run, a diagram with a lot of writing on it.
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.
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”…
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:
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!
Wonder if you saw it, this cloud mystery? First the pretty and the plain:
Now for that icy mystery yesterday afternoon:
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.
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.
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:
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.
(What about those gorgeous Cumulus congestus and Cumulonimbus calvus clouds over toward and well beyond Charouleau Gap about this time? Maybe later or tomorrow.)
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:
Welcome to one of the great cloud blogs of our time today, great as in volume, not in eloquence or anything like that.
A humorous final note: Here are two model runs only 6 h apart from last evening. The first one, from 5 PM AST global data, valid on the 26th, brings that Mexican Pacific hurricane back into AZ/NM as that strong low drops down into Cal! How crazy izzat?
The second panel was the model output from just 6 h later for about the same time. No trough nowhere near Cal as is shown in the first panel, and our powerful hurricane stays well offshore. Still, it was an intriguing glitch of a magnitude you hardly ever see.
Many of you probably were gasping for air after having seen the WRF-GFS model outputs from last evening’s 5 PM AST global data.
A large hurricane, really more the size of its typhoonic big brothers in the western north Pacific, and one that also dwarfs the late tropical remnant, “Newton” , that came through here a week or so ago, is shown to move along the SAME path as Newton into Arizona in about 13 days from now.
For those few of you who did NOT peruse the 00 GMT, CUT, Z output, here are the fantastic fantasy hurricane depictions that this model, with all of its calculating power, shows entering AZ on the 26th. Kind of fun to see even if it is bogus because it indicates that such a strong tropical cyclone could come through here one day.
Below, from IPS MeteoStar, these, maybe the best fake AZ hurricane depictions I have ever seen. Note all the isobars, i.e., lines of equal pressure with this tropical cyclone in AZ, and then remember for all its rain, little Newton had virtually no signature on pressure maps! Hell, the pressure didn’t even fall at Nogales as Newt approached. Pitiful.
But it wouldn’t be like that in this fantasy hurricane. Tremendous pressure falls would occur as it entered AZ giving your microbarograph quite a workout as the pressure plummeted and then went up as the center passed by.
You do have a microbarograph don’t you? If you don’t, think about it.
Next, you’re curious, though, about what steering pattern caused this hurricane, previously shown to stay far offshore and dissipate over some jellyfish and plastic particles way out in the Pacific in the models.
Let’s look, again from IPS MeteoStar at the steering situation at 500 millybars, or in around 20,000 feet or so:
What you need to have any confidence is a big trough along or just offshore as we had with Newt, not a slight little itty bitty eddy aloft that has to be in exactly the right location at EXACTLY the right time. I mean, its like a ball that goes for a home run after it bounces of the center fielder’s head1 …
Hold your cash on the sand bags.
Finally, there’s really nothing from the spaghetti factory that supports this. Boohoo. What you need in spaghetti is strong support for a trough along the coast, not the below:
Spectacular Altocumulus castellanus and floccus (no virga) passed overhead during the morning. I hope you documented them with a few photos.
Have to depart from clouds and weather to tell this tale. Yesterday I stopped here to let the mighty Zeus rest a little. I let him graze “off leash” on some of the still-green nettle grass in a gravel parking area next to our cottage. I then went to get a pail of water for him, the pail being on the north side of our house. When he saw I was leaving, he immediately followed me like a dog. It was kind of cute.
But as we got to the gravel outside the north porch of our house, our two dogs, Banjo and Emma were going nuts at the sight of a horse outside the north windows.
Zeus got distracted by all of the commotion in the house and went onto the porch to look in one of the windows to see what was up, or maybe he saw his own reflection and thought it was another horse? Here is the hilarious scene:
1This actually happened in South Dakota, at Mitchell’s Cadwell Park, during a baseball game I played in ’72. I was catching in those days for Mitchell Commercial Bank. Our center fielder, a track star, ran to get a scorching line drive to medium depth center, and racing to his left, reaching up to grab it, the ball instead bounced off his noggin and went some 40 or 50 feet over the fence! He was OK. We had no “concussion protocol” in those days. Had a chance to bat against the legendary Canova, SD, pitcher, Lee Goldammer in that game. Whiffed on three pitches; was maybe at bat for 30 seconds.
Former Hurricane ‘Newt’ brought some real humidity, low clouds with unusually warm bases (around 15-20 ° C) to Tucson and Catalina yesterday as its remnant center passed just about over us.
Old Newt was “dragging” here as a tropical storm, aloft it was pretty strong still, brought near hurricane force winds on isolated, high, mountain tops. Mt. Hopkins reached 59 kts from the ESE before the “eye” passed nearby and the winds turned to the west. And in the Rincon Mountains a gigantic 6.39 inches was logged, and a site on Mt. Graham reported 6.43 inches. (Thanks to Mark Albright for these reports.)
While Sutherland Heights received only 0.29 inches in that all day rain, there were eye-popping totals in the Catalinas. Take a look at some of these, Dan Saddle near Oracle Ridge, nearing 6 inches in 24 h! Below, 24 h totals ending at 2 AM this morning, which pretty much covers Newt:
Horseshoe Bend Rd in Saddlebrooke
Oracle Ranger Stati
approximately 0.5 mi SW of Oracle
Edwin Rd 1.3 mi E of Lago Del Oro Parkway
approximately 1.5 mi W of Charouleau Gap
approximately 1.1 mi NE of Charouleau Gap
NE corner of Catalina State Park
CDO @ Rancho Solano
Cañada Del Oro Wash NE of Saddlebrooke
CDO @ Golder Rd
Cañada Del Oro Wash at Golder Ranch Rd
Oracle Ridge, approximately 1.5 mi N of Rice Peak
CDO @ Coronado Camp
Cañada Del Oro Wash 0.3 mi S of Coronado Camp
Samaniego Peak on Samaniego Ridge
Dan Saddle on Oracle Ridge
Catalina Hwy 0.8 mi W of Palisade Ranger Station
Sabino Creek 0.6 mi SSE of Marshall Gulch
Your cloud day yesterday; we don’t talk about today. That’s for tomorrow.
The day began with one of the great examples of Nimbostratus, that technically a middle -level cloud greeted us at daybreak in what was one of the great examples of the phantom cloud, the true precipitator, usually hidden from view by lower clouds such as Stratocumulus. But, yesterday morning, there it was, “Ns” naked as could be. I know many of you have been looking for a good shot of Nimbostratus to add to your cloud collection for a long time and I could feel the joy out there when I saw it myself. I only took a couple of shots myself, wish now I had taken more of an extraordinary scene.
Then, as the light rain here moistened the air hour after hour, low clouds, such as Stratocumulus and Stratus fractus began to form along the mountains, producing some interesting “tracers” of the chaotic air movement over there by the Catalinas under nearly calm conditions. Newt disappointed in his wind accompaniment.
Later in the day, as the highest, coldest cloud tops associated with those beautiful Nimbostatus clouds moved off to the NE, and our cloudscape became a mix of deeper Stratocumulus with Cumulus and isolated Cumulonimbus cells, they produced true drizzle and misty, visibility-reducing “warm rain”, that rare type of rain that falls here from clouds lacking in ice, began to be observed producing Hawaiian looking rain on our mountains, delicate shafts of rain whose small drops slanted away from the base.
Here, you might well erupt with, “This doesn’t look like Hawaii, but Ocean Shores, Washington, or some other coastal location along the West Coast on a spring day having Stratocumulus with drizzle!”
You would be correct in that eruption.
Below, an example of drizzle drops on your car’s windshield:
Later, it was to look little more “Hawaiian”, but if you’ve been to Hilo, you know its mostly cloudy all day.
“Warm rain” or rain due to the colllision-coalescence process, is also mainly associated with “clean” conditions, ones low in aerosol particles that can act as cloud condensation nuclei. The fewer the “CCN” the fewer are the droplets in clouds, and the larger the individual cloud droplets are when saturation and cloud formation occur. So, by yesterday afternoon, certainly, it was doggone clean here, no doubt aided by washout in that light rain we had.
Particularly heavy rain with low visibility fell just south of Catalina yesterday afternoon around Ina and Oracle just after 4 pm. However, that rain did not have those HUGE drops that we see from unloading, deep, Cumulonimbus clouds making this observer think as heavy as it was, it may have been due to a Cumulonimbus topping out at less than 20,000 feet, where the temperature would have been too warm for ice. The 500 mb temperature yesterday was a tropical-like -3.7° C on the TUS sounding, almost unheard of with a rain situation here. This, another sign of tropical Newt, since tropical storms/hurricanes have warm cores.
lacking in those huge drops we see in our thunderstorms, this rain likely formed from the “warm rain” process except maybe in the very heaviest rain areas. It was a special day.
You probably noticed how quiet it was; no thunder around, for one thing, indicating the updrafts in the clouds were not very strong, and that was another indicator that the clouds may not have contained ice. Without ice, hail and graupel, soft hail, you don’t have lightning.
The lack of lighting, the all day off and on rain, such as you might experience at Hilo, Hawaii, on the windward side, made it seem like you were in Hilo, Hawaii, or one of the other wet spots on the windward side of the Island.
This September 8-10 model-projected Arizona deluge caused by a dying tropical storm? Then followed by four more days of rain around here?
But you wait a lifetime to see model outputs like this, and so I’m going to save it here, even if it is “fantastic”, “phantasmagorical”, surely imaginary in a sense, is model craziness, etc.
Nevertheless, treasurable moments in model output have been given to us desert dwellers overnight, the kind of rain-in-the-desert projected events that Hallmark cards were made for.
Here are the panels from IPS MeteoStar, a division of Sutron, where you can buy meteorological sensors, real good ones. I am posting so many of these panels, which is a little crazy in itself, because in 24 h this series (linked to above) will be overwritten by the next model run from 5 PM AST global data today, and we will likely never see such a wet series again foretold in a model. in our lifetimes. Who knows, it COULD happen, but prepare for a broken heart:
Now that most have left this blog to go elsewhere, let us have some spaghetti to see if there is any hope that a tropical storm-sucking trough will be along the West Coast, and in a position to draw a hurricane northward along the Mexican coast by its southerly steering winds aloft.
As you can see, a trough (emphasized by the blue lines above) is destined to lie along the West Coast, in a position to steer any tropical storms toward Arizona that might be moving up the Mexican coast. So, it looks like the chance of a tropical storm entering the state is certainly a fair amount greater than zero around the 9-10th of September.
Also, I am also posting way below a new (!) not-previously-published. but rather rejected- by-important-scientists-a-long-time-ago-manuscript FYI!
Very exciting! (Hah!)
Its published now, though, isn’t it???!!!
Its about science and how it works, and how it has failed; examples given. I put it down toward the bottom of a normal blog because I am shy.
Clouds from a few days ago, August 26th, now that the “choke point” in uploading photos to Word Press has been, at least temporarily ameliorated.
Here’s the sequence as a great cloud bottom drifted toward us from Pusch Ridge on the afternoon of the 26th. If you saw this coming, you should have been clearing channels around the house for excessive water flow. I forgot to.
Unloaded 0.45 inches at this site. 1.69 inches up on there on ol’ lady Lemmon. We sure needed this dump! Below, one of the great cloud bottoms of our time, that of a Cumulus congestus cloud, filled, as we say here, with rainy portent (maybe hail, too):
Pedagogical or possibly, pedantic (boring) module
Update alert for the posting of new (!) not-published rejected items by this Arthur:
(the original title, submitted first in 1997), final rejection in 1999 (Bull. Amer. Meteor. Soc.)
The reviewers, Harold O., Danny R., and someone named “Anonymous Reviewer B”, guessed as, “”B”, for “Bernie S.”
Those in the cloud seeding culture don’t need the names spelled out. Harold O. is part of the “old guard” cloud seeding culture, while Danny R. is part of the new cloud seeding guard, one that has gone on to be a science superstar since his early work at the Hebrew University of Jerusalem under the leader of the Israeli cloud seeding experiments. He did some work there on the clouds of the Mediterranean and satellite interpretations of them (available in Hebrew only the last time I checked).
While Danny R was there during the time of the reporting of the benchmark Israeli 2 randomized experiment by the leader of the experiment (1976-1986) he himself was not involved in those (ultimately flawed) analyses. Later, he participated in the unraveling of the 2nd experiment with Israeli statistician, K. Ruben Gabriel in 1990, J. Appl. Meteor. Half of the 2nd experiment’s results had been previously omitted, an omission which produced an apparent, unambiguous “confirmatory” success of the Israeli 1 experiment, for the short of it.
The 1990 development in Israel, in essence a retraction of what everyone thought was an unambiguous cloud seeding success, plus the fall of the equally important, earlier benchmark randomized experiments in Colorado, at one time also claimed to have proved cloud seeding by the National Academy of Sciences (Malone et al 1973), were the primary reasons for composing the piece being posted today. You may also know that your very own Catalina “cloud-maven” was in Israel in 1986 for 11 weeks, in doubt of those “hard-to-rain” clouds that were being described by the leader of those experiments, resulting in “Rain from Clouds with Tops Warmer than -10° C in Israel”, (1988, Quart J. Roy. Meteor. Soc.). This was to some degree the first crack in those experiments. (Of course, I would say that!)
How could such glowing, but ultimately critically flawed journal papers appear ultimately involving hundreds of journal pages? What went wrong with peer reviews?
I attempt in this piece to describe in this piece how science is supposed to work, and these pretty amazing chapters of science in cloud seeding, and offered some possible solutions.
At one time, Prof. Peter V. Hobbs, named to write up a status piece on Clouds-Climate for the World Meteorological Organization (WMO) in 2003 or so, was going to use the “rise and fall” of the Colorado and Israeli experiments in this piece I have just posted. He was going to demonstrate how we scientists can think we have proved something, but upon closer inspection, find that we have not proved at all!
Peter Hobbs was concerned that the then many unknowns about clouds were not being treated properly in climate models (being parameterized too crudely), and therefore those parameterizations of clouds in climate models could lead to erroneous conclusions concerning the amount of global warming that might be ahead.
In his take on this MS, and that “rise and fall” section in particular, Peter, who was not one to dole out compliments very often said of it, “This is pretty good.” Peter had not reviewed it beforehand.
Ultimately, Peter contracted pancreatic cancer and was unable to submit his status summary to the WMO.