About real clouds, weather, cloud seeding and science autobio life stories by WMO consolation prize-winning meteorologist, Art Rangno
Author: Art Rangno
Retiree from a group specializing in airborne measurements of clouds and aerosols at the University of Washington (Cloud and Aerosol Research Group). The projects in which I participated were in many countries; from the Arctic to Brazil, from the Marshall Islands to South Africa.
OK, there are a lot of graphics and discussion today, much of it unnecessary as usual, but there it is. We’ll begin with yesterday….not today.
Yesterday morning’s WRF-GOOFUS run once again had rain in Arizona/Catalina area. Was heartened since the prior 24 h’s predicted rain had disappeared in the three runs after that. Here’s what came out YESTERDAY morning for Wednesday the 12th. Cool, eh? Below this map is the corresponding upper level map.
Valid for Wednesday December 12th at 5 AM. Green areas denote where precipitation fell in the prior 12 h.Also valid for Wednesday, December 12th. Note how the jet stream at this level pours down from the Pacific NW into California and then across northern Mexico.
Then the same thing happened as the day before, that Catland rain disappeared again in the model runs up to last night’s. Not good.
But, I am happy to report that the rain is BACK, and why I am at this keyboard this morning. The very latest run, one that was conducted using the data from last evening at 11 PM AST is shown below with AZ rain again, this one valid for 11 PM AST on the 11th.
Now you might wonder why I would go through all these machinations to show you likely model illusions of rain here in the distant future, providing you only those ones that have rain here in them.
That’s because this is not about being objective, but rather SUBJECTIVE, really caring about rain here.
There is no way I am going to show you model outputs for our region that have no rain in them! I only show those ones that have what I want to have happen here, rain, and that’s why I show them. Its a very biased sample that you get. But its quite altruistic of me since any rain ahead MIGHT yet help the spring blooms that we ALL enjoy. So, by being subjective, I bring hope where maybe there wouldn’t be any. You can see I am really thinking of others in being so biased.
“What does the spaghetti say?”, you ask, as a person having a tremendous amount of weather perspicuity. “These outputs any good?”, you continue in a burst of meteorological eloquence.
Grudgingly, I am providing the NOAA “ensembles of spaghetti” map for the same time, December 12th. I’ve added an arrow in case you don’t know where you are.
Ensemble members valid for December 12th, affectiionately known as a spaghetti plot. Remember this crazy lines are due to deliberately putting little errors in the initial analysis to see how much difference they make from the real forecast that came out using the actual data. The wilder the lines, the less reliable the longer term forecast.
Now, the blue lines indicate more or less where the heart of the jet stream will be, the red lines, the periphery, or it when they are separate from the blue lines, a separate branch of the jet stream bordering the sub-tropics.
As you see here, the bulge toward the equator in the RED lines over our area strongly indicates that a trough WILL be here in the southern branch of the jet stream on December 12th. Often however, those troughs in that southern branch often only bring high or middle clouds; no rain. Need a bunch of blue lines down thisaway to get rain, and as you can see, MOST of the blue lines (“members”) are well north of us.
What to conclude from this?
That distant rain on the 12th shown repeatedly by a biased Mr. Cloud Maven person, would still have to be considered an outlier model run. But having said that, these spaghetti plots have been getting more supportive of a rain. Instead of a 5% chance, now maybe its up to 20%, based on the map above because some of the blue lines are beginning to be extruded toward Arizona.
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Weather coming up elsewhere in the US
BTW, in these model runs, one of the things that is a real eye-opener from the lastes run from last night is a gigantic mass of cold air that comes down into the Rockies after December 12th and affects most of the US. Awful for Christmas travel. Here’s a predicted surface weather map for December 15th, annotated to help you figure it out.
That mass of cold air is shown to move very rapidly into the US from the Arctic, and so the air will not be modified much by its southward movement–the configuration below is probably good for -40 F or even lower in Montana and some other high valleys in the northern Rockies. Hope you’re not traveling then…
Looks, too, like that icy air will be traveling over ice and snow until it reaches the US border according to this snow-ice coverage map from NOAA below. No wonder Canadians mass on the US border! Its apparent from this map! That will also keep that air relatively unmodified (keeping it as cold as possible) until it hits mostly bare ground in the good ole USA.
Some 8 days ago a spaghetti plot indicated with confidence that a “warm in the West”, “cool in the East” pattern would develop. Well it has materialized. Thanks to Hamweather, this chart shows the records set with that pattern so far. They’re not so numerous, but the forecast of a strong trough off the West Coast pulling warmer air north into the West and a trough in the East dragging down cold air from Canada has verified. The point of this is that those strange looking “spaghetti” plots can have some power if you’re not overwhelmed by all the lines.
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BTW, after learning about this spaghetti verification, you might want to consider adding to your collection of cloud maven junior tee shirts this new attractive—well, stunning really — “I love spaghetti” black Tee offering with a truly gorgeous multi-colored example of the NOAA-NCEP “ensembles of spaghetti.”
Here’s last night’s example from NOAA-NCEP to get you excited about getting that tee:
I think you’d look great in it, and, of course, most sophisticated when it comes to being a cloud maven junior and advertising that you know about something like this. Most people have never heard of these plots, which puts you ahead of masses.
Remember the “You are here” Milky Way Galaxy tee showing where the earth was? Well this one would be as good for you to be seen in as that one! And this new cloud maven junior tee is only $29.95 plus shipping and handling, which brings the total to $75.42. (I’ve been studying how the online vendors do it….)
Think of all the people you might meet that would ask you about your tee by saying, “Huh?”
Then you would go on a long spiel, making new friends, by pointing out areas on your tee where the signal is strong and the forecast reliable, and where the forecast model is clueless. In the above example tee, that trough north of the Hawaiian Islands 15 days from now looks pretty solid while things are pretty clueless in central Europe, roughly diagonal from the trough north of Hawaii. You know where Hawaii is, don’t you?
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The weather ahead, way ahead…grasping for a switch to be turned on
A great pattern popped out yesterday. Hasn’t been seen since, but it was so exciting that I thought I would share it with you. We’ve been in a stagnant pattern for a LONG time now; storms racing across the Pacific into the northern half of the West Coast. As a weatherman, we’re always looking for the switch; patterns like that just don’t last ALL winter, but a tipping point happens, and boom, everything is suddenly different.
In this model run from yesterday, a tipping point happened and the storms began moving southward along the Alaskan coastline to off California in about 10 days. One of those is shown here near San Francisco. At this time in the run, December 15th, 5 AM AST, extensive rains are shown in Arizona!
While it might verify, there has not been support for this pattern since, and the ensembles of spaghetti, shown above, are not very encouraging, actually not at all, only suggesting a trough in the northern Plains States. A trough is suggested in the southern Rockies, and not a strong one at that since that trough is mainly confined to the red lines, those demarcating the periphery of the jet stream, or may even be a weak southern branch separate from the northern one. Usually doesn’t rain here with those.
But, this quasi bogus output looked so great, I had to post it anyway. I was so excited yesterday when it came out, because we know there WILL be a pattern change. There always is, even if its short-lived and isn’t a total drought buster. I guess this indicates a degree of desperation when you’re posting model outputs with little chance to verify.
With no rain in sight, and only modest temperature fluctuations ahead, some reading material is presented to you today with commentary today, a “soapbox day.”
Cloud photos from yesterday are at the bottom if you want to skip to that and avoid thinking about things because its too early in the morning to get riled up.
I will start with an opinion piece concerning climate change and climate science from Australia. It also mentions a recent event in the climo community concerning a Southern Hemisphere temperature reconstruction and the apparent rejection of what would have been an important paper by the peer-reviewed journal it was submitted to after crucial errors were found by an outsider/reviewer. The author of this opinion article also mentions “climategate” a chapter of science that had a profound effect on this writer. Now there are polemical aspects, not all of which this writer would agree with, still, its worth reading:
The link to this article was circulated to our Atmos Sci Dept by one of my best friends, and really a science hero to me, Mark Albright, the former Washington State climatologist. Mark was a mild-mannered researcher lurking in the background at the U of WA for many years until he got upset over what he (later joined by two allies there) was to show were vastly exaggerated journal-published and media accounts of snowpack losses due to GW in his own backyard, in the Cascade Mountains of Washington and Oregon. Mark felt science had been corrupted by dogma, perhaps the pursuit of funding; he has not been the same since. Believe me, I know what he has been through.
A retired distinguished professor at the U of WA Atmospheric Sciences Department circulated a counter articleto the one that Mark circulated, also worth reading for the “other side.” It appears below, along with that professor’s note about the article Mark circulated. I felt this note by the professor should be included, too:
In the headline of this second article, the word “denier” is used in its title as a pejorative, mass label for those who question some of the global warming publicity stunts (assigning particular storms like Sandy to GW) down to results published in peer-reviewed journals, such as reports of exaggerated snowpack losses. Not good, and that headline tells you where that article is headed: criticism is not to be tolerated. But it also shows that the majority of science being published on climate change supports the finding that a warmer earth is ahead. But there is a reason for that; its being pushed by the monumental amounts of money being poured into that climate research domain.
There are many of us out there that do believe that funding is pushing the research on global warming in one direction in this job-poor era we’re now in, just as it did, and still does, in the cloud seeding domain: no one ever got a job saying cloud seeding doesn’t work. In my own career–yes, Mr. Cloud Maven person had a professional research one, and one spiced with controversy1 over several decades–the opinion article from Australia rings true in many aspects about how science works and what influences a preponderance of “conclusions” that get published in journals.
In the climate funding domain, don’t look for more funds if you conclude a million dollar study by indicating that you didn’t find any sign of warming over the past 30 years, as is the actual case in the Pacific Northwest. NO ONE is going to touch that hot potato and serve a finding like that up to a climate journal. Its not gonna fly. It makes explaining global warming difficult. And as Homer Simpson advises, “If something’s hard to do, its not worth doing.”
But at the same time, a counter finding to global warming presents to those of us who try to be truly ideal, disinterested scientists, a fabulous opportunity to look into something that is not immediately explicable. As scientists, we should live for opportunities like this!
But will it happen, will some brave soul at the University of Washington or elsewhere delve into this counter trend and try to explain why its happened in a journal article? Its hoped so.
But those of us, still on the GW bandwagon, if grudgingly so due to the actions of some of our peers, know that regional effects of GW are dicey. Some areas will warm up more than others; cooling is possible if the jet stream ridges and troughs like to hang out in different positions than they do today. And of course, if we smog up the planet too much, all bets on warming up much are off since clouds act to cool the planet, and pollution makes clouds last longer, especially over the oceans where pollution can interfere with drizzle production, which helps dissolve shallow clouds, and pollution causes more sunlight to be reflected back into space. The cloud effects are being more carefully, precisely evaluated in our better computer models.
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It is ironic, too, that the second article, the one passed along by the professor, ends with the mention of plate tectonics “as the ruling paradigm of science” as it is.
But, some word about how that paradigm came about; it was a “long and winding road.”
Alfred Wegener, a meteorologist, first proposed the theory of continental drift/plate tectonics around the turn of the century. A nice account of this science chapter about origin of the theory of plate tectonics is found in the book, Betrayers of the Truth, by then NYT science writers, Nicholas Wade and William J. Broad.
Because Alfred Wegener was a meteorologist, however, and NOT a geographer, namely was an outsider to the official science community studying the continents and how they got that way, his ideas were laughed at, not taken seriously for more than 40 years! Only in the 1960s was the idea of plate tectonics accepted.
I mention this tectonic chapter of science because there is a similar chapter that reappears constantly now in the climate debates. Several of the strongest critics of GW results, critics that have delved deeply behind the scenes into published findings of climate change in a scientific manner, much as this writer did concerning cloud seeding experiments in the 1970s-1990s, are criticized for being “outside of the group”, just Alfred Wegner was in his day rather than those “in the group” considering and acting on whether the findings of outsiders are valid.
Fortunately, this is beginning to change because, guess what? Outsiders have found some pretty important stuff that HAD to be addressed in spite of the desires of some idealogues out there pretending to be objective, disinterested scientists. Science as a whole, still works.
A cloud note: Alfred Wegner is also known for proposing the idea that ice crystals in the presence of supercoooled water (a common event in the atmosphere) grow and fallout, leading to precipitation at the ground, known as the Wegner-Bergeron-Findeisen mechanism. Every 101 meteorology textbook points this out.
The last photo below is a demonstration of that effect; those sunset supercooled Altocumulus shedding a few ice crystals that grew within them.
Yesterday’s clouds
7:33 AM Cirrus fibratus radiatus. Sometimes perspective makes banding look like its converging or radiating. I estimated that this was not the case here.4:31 PM Parhelia-Sundog-Mock Sun in an ice cloud with hexagonal plate llike crystals, ones that fall face down and cause the light to be refracted and separated. Here’s is a link explaining this phenomenon.5:24 PM. A classic Arizona sunset due to the under lighting of Altocumulus perlucidus. Some very fine virga from these clouds can also be seen. When the virga is this fine, the concentrations, as you would imagine are very low and the crystals falling out are especially beautiful because they have not collided with other crystals and broken into pieces as happens in heavy virga shafts.
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1Some examples of the controversy the writer has been involved with:
“We don’t hate you but we don’t love you, either.”
This quote from a leading US cloud seeding scientist to the writer at an American Meteorological Society conference on cloud seeding and statistics after his cloud seeding experiments had been reanalyzed by the writer.
“I want you to leave my office and don’t come back. Just do your own thing.”
This quote from THE leading cloud seeding scientist of the day when I went to his country to see for myself the clouds he was describing in peer-reviewed journal articles, descriptions that I had doubts about. His descriptions were later shown to be far from reality.
And, from an outside observer, and well-known cloud researcher at the National Center for Atmos. Research in Boulder, a comment to the writer when he visited the University of Washington:
“I think the (cloud seeding) community sees you as a ‘gadfly’.”
From the Oxford Concise Dictionary, “gadfly”:
“A cattle-biting fly; an irritating, harassing person.”
November will finish out dry. And, with the extremely dry October we had followed by a rainless November (Correction here on November 25th! Egad. We had a nice rain here on November 9-10th in which we received 0.48 inches, about half of November’s average! Brain fading…. End of correction.)
….you can’t help but start to fret over March, and those great blooms that erupt so quickly in our deserts. From what I have experienced and have learned, fall and early winter rains are critical for bountiful spring blooms; January and February rains, not so much.
Rain is beginning to show up in the first week of December, but, that far in advance, its showing up beyond the model’s credibility horizon of about 6-7 days. Also, the panels below are from the 06 Z (11 PM AST) model run, one that is not plumped up with as much global data at the runs at 12 Z (5 AM AST) and 00 Z (5 PM AST), so even more likely to be faulty.
Still, its the best I can do for finding future rain in Arizona/Catalina. I am posting these maps at full size to make them look more important, have more visual impact, maybe put some pressure on the next model run to come up with something similar.
Will report back when these two rains show up again…or if some interesting clouds float by.
May insert some filler material blogs in the meantime…
The End.
Valid 11 AM AST, December 2nd. Green areas denote where rain has fallen over the prior 12 h (fell the night of the 1st-2nd)Valid 11 AM AST, December 8th.
7:09 AM. Altocumulus, trending toward perlucidus. Height? Aout 13,000 feet above the ground, from reading the TUS sounding. Temperature? -10 C (14 F). No ice trails visible.12:13 PM. Nice, high-based small Cumulus (or Altocumulus castellanus) with snow virga moved over the SE part of the sky in the early afternoon. Bases were around 11, 000 feet above the ground at -5 C (23 F). Sprinkles (very light rain showers-its not drizzle) reached the ground in a few isolated areas.2:02 PM. A somewhat rare example of Cirrocumulus and Altocumulus probably at the same level in proximation with one another. Cirrocumulus (Cc) is defined by a very fine granulation and no shading. The fine granulation gives the impression here that its much higher than it really is. Altocumulus clouds are defined as having much larger elements, shading allowed. Well, even if the Cc was at a slightly higher level, this is a good example of the difference between the two. Tell your friends.5:10 PM. Mind drifted toward road runners for some reason…. This is Cirrus uncinus with long trails of ice crystals streaming back from the little cloudlet that originally formed, like an hour or two prior to the photo. The trails survive because its a bit moist up there below where the cloudlet formed.
The weather ahead
A huge buckle in the jet stream is forecast to form right off the West Coast in about a week, and its a pretty spectacular interruption in the pattern of a jet stream whizzing by far to the north of us that we have had now for sometime. Below is an example of ‘now” in the jet stream winds, and below that, a forecast panel (from IPS Meteostar) showing this striking change a week from now. There’s a big (“high amplitude”) trough in the eastern Pacific, a high amplitude ridge (hump in the jet stream toward the Pole) in the West and another big trough in the East.
Patterns like this are usually associated with extremes in temperatures; warmth in the West; cold in the East. It is certain when this pattern materializes in about a week, some high temperature records will fall somewhere in the West and some low temperature records will fall in the East. In the West, warm air is drawn far northward, aided by low pressure centers spinning around in the eastern Pacific, while in the East, cold air zooms down with high pressure centers from northern Canada.
Why bother talking about a forecast a week in advance?
Because it has a lot of “credibility” in our ensemble (spaghetti) plots. Here is last night’s “ensembles of spaghetti” plot produced by NOAA for one week in advance. Look below at these “ensemble members” the different blue lines, ones that are loaded with slight errors at the beginning of the model run, to see how strong the forecast a week ahead is.
Those bunched blue lines in the eastern Pacific (see arrow) inspired this whole spiel about the coming change because its a nice example of when the plots show something reliable in the way of a longer term forecast, and in this case, a forecast that also shows a big change in the weather patterns over thousands and thousands of miles, from eastern Pacific to the western Atlantic.
If you’re looking around this whole plot, you’ll see the lines are also very bunched in the extreme western Pacific and westward across Asia. Those blue lines are always bunched over there because there is little variance in the flow in that region; its locked into a pattern by the geography, unlike in the central and eastern Pacific and into the US where the jet stream is MUCH more variable. A simile: imagine a fire hose turned on at the hydrant, the part of the hose at the hydrant stays in place while the end of the hose flops wildly around. Its something like that; western Pacific to eastern Pacific.
Our weather?
Well, after all that gibberish, not much change will occur here; its everywhere but here! Seems we’re doomed to another dry seven to 10 days ahead with occasional periods of high clouds and great sunsets as weak disturbances from the sub-tropics pass by, ones that can only produce Cirrus clouds.
Kind a bored looking at the same model runs for 10-15 days ahead now, ones that close out November with no rain even nearby for Catalina. Doesn’t seem to be even ANY HOPE for rain here, that is, some bizarre model outlier forecast with rain, as we saw a few days ago. But then, I had not had any coffee yet…
Thought I would drink some coffee to see if I’ve missed anything in these latest computer model images. I’d kind of forgotten what Consumer Reports Health Letter had warned about when you’re bored and trying to do stuff. Talked about the effects of caffeine on boredom. I reprise a portion of that CR note here, in case you, too, are looking at repetitious model outputs with no rain in them. Note the part in in this note below about “repetitious images” and “infrequent changes in patterns on a screen”; yep, that’s what we’re dealing with here in these model runs now.
OK, finished second cup, caffeinated coffee, BTW, now going back to look at those model forecast maps to see if I missed anything, subtle or otherwise…. You, too, can look at the 5 PM AST model loop here (from IPS Meteostar), but drink some coffee first.
Prepare to be “re-bored” as I have just been.
Not even the NOAA NCEP’s “ensembles of spaghetti” offer hope; no “outlier” model forecasts with Catalina rain in them anymore (for now, anyway). Bunched blue lines, demarcating jet stream, stay to the north.
But, paraphrasing Scarlet O’Hara, “6 h from now, there is another model run…”
Yesterday’s clouds
Had some great Cirrus spissatus and other varieties/species of Cirrus overspread the sky yesterday, eventually thickening into Altostratus translucidus (sun’s position still visible). Here are a couple of shots, including a sunsetter where you can see just that bit of virga hanging down.
1:19 PM. Cirrus clouds began overspreading sky from the southwest (direction that photo was taken toward).2:16 PM. Cirrus spissatus (the only Cirrus cloud that can have shading) encroaches from the southwest.4:29 PM. The Cirrus clouds have thickened in places, usually downward, to large patches of Altostratus translucidus (thin enough so that the sun’s position is still visible). Its also possible here that the Altostratus clouds were below a higher layer of Cirrostratus.5:26 PM. Under lit Altostratus clouds with likely a separate higher layer of Cirrostratus.
Today’s clouds?
Your call: ________________________________________________________________
These are sad times when you can’t find a model run with at least some AZ rain in it. The last two USA model runs, compiled from global data taken at 00 Z (5 PM AST) and 06 Z (11 PM AST) don’t have ANY rain in Arizona. Prior two runs did, ones that came out during the day yesterday.
The rains in yesterday’s model outputs were late in the month and into early December. I exulted all day yesterday because the “ensembles of spaghetti” were strongly suggesting those rains were associated with “outlier” model runs, more extreme ones that couldn’t be counted on.
But, those rains kept reappearing. I unilaterally decided, i.e., had a “hunch”, that the “ensembles” themselves were, in a sense, “outliers”, lying about no rain in AZ. They were missing something.
Looks like I’ll get burned on that “hunch”, as would be expected by an objective scientist. Now I will talk about something else…
Maybe the costly and more accurate Euro model, which could save thousands of lives by being free and warning poor people of big storms and winter cold way in advance, has rain here in it here, but I am too poor to afford to look at it. The Canadian Environment Canada model1, built on the Euro one, only goes out to 144 hours, not the 5000 hours ahead that we seem to need to see a rain predicted in Arizona someday.
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BTW, as an example of that Euro model’s non-availability, if you go to the University of Washington’s model outputs web page, you will see the daunting words for the Euro-UK MET model, “restricted.” The letters are in RED to make sure you know you can’t get it. Don’t hit the latest run link to the right, you will be asked to enter your ID and password, and because you don’t have one, you are punished by not being able to go back to where you started. Rather, you end up in an endless loop asking for your password and ID to make sure you don’t come back again and mess around thinking you might “get in.” You will have to close your browser. If you have a password and ID, then post that model somewhere, oh, man, you are in for fines and, who knows, maybe some jail time.
Its a sad forecasting world out there.
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Here are the sad (lotta “sad” today) conflicting rain/no rain model outputs for the SAME time and day, the first panel from yesterday morning when I was happy, and the second panel below, from the very latest run:
Rainy AZ prediction for November 28th based on yesterday’s (11-19) 5 AM AST global data. See green pixelation in Arizona; that’s model predicted rain. Was happy to see this late yesterday morning.18 h later, the model run from last night’s data at 11 PM AST also valid for November 28th. Look at that huge dry region in the whole West that has replaced a substantial storm! Unbelievable. There a friggin’ high pressure center almost exactly where there was a big low pressure center! We call this, “Forecasting hell.”
Today….
On to happier things, should have some gorgeous clouds and skies today as a tropical system skirts SE AZ. Virga likely. Keep cameras ready for a great sunset.
The End.
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Why would they name their organisation, “Environment Canada” when you already have to go to a Canadian site to look at it?
Here’s is the latest model run from our USA WRF-GFS (aka, “goofus”, as the Europeans might call it, looking down their noses at our inferior weather predicting model compared with their “ECMWF” model as described (here) in the November 9th issue of Science.
It was an upsetting read, BTW. Seems the Euros use bigger, faster computers than we do, ones that they were able to afford by charging a lot of money to see the results. Very bad.
In case you want the meat of that Science article: “From the BEGINNING (this writer’s emphasis) ECMWF has been the world champ in medium range forecasting. Today ECMWF forecasts remain useful into the next week, out to 8.5 days. That leaves the rest of the forecasting world, inculding the U. S. National Weather Service with its less powerful computer, in the dust by a day or more.”
What have our guys (includes women) been doing all these years? (Just kidding, maybe.)
OK, onward with what we have to work with…..
This WRF-GFS run is just from last nights 11 PM global data crunch, the VERY latest as of this writing. I picked it out from earlier runs to show because this run latest has a lot of rain in Arizona. Namely, it was a subjective call to display a few snapshots from it. Displaying the results of this run has nothing to do with scientific objectivity. Enjoy; it might not be real rain that falls to the ground, only real in the model’s calculations. Still, its great to see and think about.
Instead of showing the full size of these model outputs as I normally would do, I thought I would size them in proportion to their credibility based on the Science article. We can’t see the better ECMWF-British model results unless we pay a lot of money, so this will have to do. Unless you click on these below, you’ll have to use a microscope…
Valid for November 29th, 11 PM AST, only 264 hours away!Valid for 11 AM AST, November 30th, 12 h laterValid for 11 PM AST, November 30th–off and on rains now for TWENTY-FOUR hours!Valid for 11 AM AST, December 1st. Still raining around here.Valid for 11 PM AST, December 1st. Rain still falling in the 12 h ending at this time.
So, once again, our late November-early December storm has returned to the model fold. Its been coming and going. For example, the 5 PM AST global model run had NO RAIN in AZ, so I didn’t want to show those results.
But just ahead….this
In the nearer future….. Seems the Environment Canada computer model, built around the SUPERIOR ECMWF model, has rain here in about 48 h from now resulting from a tiny, weak low that ejects from the deep tropics right over us. Cool, though the air itself would be warmer and more moist than we usually see at this time of year in a rain situation (higher dewpoints). Must regard this as a serious rain threat now. Here’s a snapshot of that rain day from Enviro Can (see lower right panel for 12 h rain totals and areas covered–would fallen overnight tomorrow night into Wednesday morning. The whole better than the US model runs is here.
Yesterday’s clouds
Another fabulous early winter day in Arizona. Out of state license plates picking up in number. Can’t blame ’em. Here’s a sample of yesterday’s skies and another great sunset:
2:06 PM. Cumulus humilis and fractus (shred clouds).5:23 PM. Small Cumulus and distant Cirrus add highlights to an Arizona sunset.5:25 PM, looking south.
Once again we were treated to a spectacular sunset, another one in a long series of occasional sunset spectacles, ones that probably go back before the 1900s. We didin’t have color film in the 1800s, so we can’t be for sure if there were spectacular sunsets here except via artist’s renderings, of necessity, of course, analog ones comprised of subjective estimates of sunset colors being seen, not the real ones. I you would like to read about clouds in paintings over the centuries, go here and here. In this second link, you will find that Leonardo da Vinci was quite interested in Cumulonimbus downbursts gave painting them a shot. Its not that great, to be honest.
We meteorologists often sadly ruminate on the career of Leonardo, thinking that had he only turned his attention away from art, sculpting and the like, and instead turned to the problem of weather forecasting, how much farther ahead we would be today. A real shame. Maybe we wouldn’t be relying on spaghetti plots so much.
Also got a trace of rain here in Catalina–you could sure get that smell of rain as soon as you went outside this morning.
5:25 PM. Altocumulus opacus under lit by the setting sun. Altostratus clouds were above that layer.
We also had some real interesting mottled-looking skies yesterday due to Altocumulus underneath a layer of Altostratus translucidus. Those underlying Altocumulus clouds were in a layer with a lot of instability (temperature dropped rapidly with height in it) and so there were many little spires (castellanus and floccus varieties). This happens because a little bit of warmth is added to the air when moisture condenses in it, and that bit of warmth was able to drift upward. As that happens the air around those little cells of updrafts settles downward gently to take the place of the rising air creating voids. So, you get clear air spaces between the little cloudlets. I think that’s what happened here.
3:10 PM. Altocumulus castellanus and floccus invade sky under Altostratus translucidus (thinner version).
Let see, what else is going on…. Most of that plume of moisture from the tropics is gone, and so only expect a few Cumulus today. Oh, yeah, big storm about to slam northern Cal and Oregon. Take a look at this map series from the Washington Huskies to get an idea of how its growing in size before hitting the coast.
No rain predicted here in past two model runs (last evening and last night, 06 Z) for the next 15 days, but we are quite sure that’s wrong. Will be looking for that end November early December rain to reappear because I have a subjective hunch it will. If it doesn’t reappear, I will likely pretend I never said anything about it, in keeping with long tradition in public weather forecasting.
BTW, and belaboring the point a bit, here’s an example of how errors in public forecasting SHOULD be handled; “right up front”, in this case, an anonymous Seattle forecaster addresses the terrible temperature forecast he made the previous day following day:
12:18 PM. Altostratus translucidus (sun’s position is visible).2:34 PM. More Altocumulus opacus with virga. Large clearing approaches from the west.3:46 PM. Patch of Altocumulus translucidus perlucidus (thin, with a honey-combed pattern)
Today? More pretty clouds.
The weather way ahead, like on November 29th
Just after I was asserting from this typewriter that the big storm, the Great Wet Hope in late November, was surely bogus, out popped another wet forecast for AZ n the model run crunching global data from 11 AM AST yesterday. Here it is below, first panel. You MAY remember that the nice early rains that we had in November last year were associated with a similar pattern of an upper low center near San Diego.
What to think of this “outlier” forecast, one NOT supported in the ensemble of spaghetti plots (model runs where small errors are deliberately input to see how those runs change from the ones based on the actual data). There very little support for panel 1 in those “perturbed” runs, but there it was again, a big AZ rain!
Well, its still unlikely, but the chance of it actually happening are now much improved. Something out there is causing the model to come up with a good rain in AZ at the end of the month. I did not think I would see any rain again in AZ in any more model runs.
And, sure enough, the model run based on data just 6 h later than the one shown in the first panel, took it away again! See the second map below and look at the astonishing differences over Arizona and the Southwest overall!
I won’t show it, but the “perturbed with errors” model runs that we look for to discern credibility in the longer term forecasts like these, STILL does not support much of a chance for a rain to be realized on the 29th.
But, that second appearance of an “outlier” in another model run….hmmmmmmm. Will be watching for a return; you start to get a feeling that it might well be seen again.
As I finish this blog blurb, the 11 PM global data should have been crunched by now, and will look to see if there is yet another huge change (well, there are always large changes, but here, I’m talkin’ for us!) Will let you know in about 2 minutes…. Stand by, generating new web window now…..
Oh, my gosh! Its changed again (3rd panel) to a huge West Coast troughy situation, completely different than the run at 5 PM AST last evening with the big ridge over us (bulge to the north). I have to post this latest map, again for late on November 29th. The situation you see in the third panel leads to another big rain forecast in AZ, though a couple of days later, early December! This is so great! Compare the second and third maps.
Now, you can really start to put some credibility in the supposed “outlier” forecast and, as a discerning meteorologist, say to the spaghetti plots with their little deliberate errors, “Go to HELL! You’re missing something big out there with those puny errors you start with.”
Calming down now, well, you can’t cast the thought of warm dry weather (seond panel) for late November out yet, but something IS being missed out there, which makes this an exciting period–just to see what happens. Though an admitted precipofile, at least here in AZ, not so much in SEA, I am putting my mental marbles on the trough in the West depictions now. Just a hunch.
