I was thinking how great yesterday was for you. Started out with a spectacular sunrise (lasted just a couple of minutes), and then you could watch for pretty much the WHOLE day, orographically-formed Altocumulus opacus and castellanus transition to ice crystal clouds (in this case, Altostratus with virga and some mammatus) right before your eyes!
After sunrise….this odd scene below of an extended Altocu lenticular cloud:
Brain’s been pretty empty lately, not much to say except “same old same old”, as here.
But then some wild computer forecasts came out last evening that were worth mentioning in light of the fires that have plagued southern California.
Because they suggest that a belt of tropical flow will break through under the gigantic ridge that has blocked storms from the entire West Coast over the past weeks.
Sometimes, as most weathermen know, such persistent ridges get too big for their britches, that is, over-extend to the north, and then fracture, letting through moist tropical air from lower latitudes of the Pacific ram into the West Coast. Often the very greatest rains in California are associated with such patterns, as you could guess since there is so much water with those lower latitude-originated jet streams that strike the coastal mountains head on. Here’s the concern, this output valid for Christmas Day:
Rain is forecast to have fallen in southern Arizona before this point, however; our measly 0.01 inches so far here in Sutherland Heights so far in December will likely be added to along with a switch to uncomfortably cold weather.
Of course, we look for support in these longer range forecasts by having some spaghetti–that is, take a look at what we call “spaghetti”, those crazy plots in which the model starting conditions are tweaked that bit to see how the model runs change. Here are some plots, also from last night’s model.
As you can see in this first plot for the evening of December 22nd AST, the clustering of blue and red lines off the West Coast, that our blocking ridge (composed of a deep mass of warmer air) is extruding all the way almost to where Santa Claus lives, yes, that far to the north. In fact, so far that it will be unsustainable over that distance fromt the deep tropics to almost the North Pole. At this point, cold air is pouring down the east side of that ridge and into the Pac NW and eventually down toward us. Does that extremely cold air make it here? Not sure yet, but its something to watch out for before that ridge fractures and allows warmer, moist Pacific air to reach us. So much uncertainty, so much fun! I am really pumped up about all this uncertainty!
Below is the spaghetti dish for the “breakthrough” flow situation shown in the prog output valid for Christmas Day with some annotation on it.
Looking at the above, I think we can count on a breakthrough flow pattern from the Pac. Where it barges into the West Coast will be subject to question over the next week or so. That really can’t be determined right now.
I am sure those in southern Cal hope, if there is a breakthrough from the Pac, it comes in farther north than shown in the model run here today! Patterns like the one shown in that run can routinely produce 10 inches in a day once they get going should something burst through at low latitudes.
The brighter side would be that the chances of a significant rain here droughty southern AZ would at last increase.
Hope you saw them and recorded them in your cloud and weather diary. I’m thinking that at the next Cloud Maven Junior meeting we should devote a lot of time to this issue. It was a rare day yesterday that the WHOLE day had that phenomenon occurring as aircraft penetrated those clouds, usually on ascent or descent. Sharp descents/ascents produce holes. See the sequence below if you don’t believe me (ppt from a recent talk):
Yesterday’s clouds: lots and lots of aircraft-produced ice
(btw, see note below about pop-up ads in this blog, ones that started to appear after downloading latest WP software)
——————About those nuisance ads—————
Note to me and the two other people that drop by my cloud or “clod” blogulations: The embedded pop-up ads are due to a WP third party plug-in that needs to be repaired. It will likely happen today.
After consultations about ads…
Oddly, those pop-ups and blue highlighting and double underlining do not seem to be present outside of my personal view of my own blog, this according to hoster, “godaddy.” Even using a different browser other than FIrefox does not show them as I have just verified.
Been busy as a briefly unretired science worker (gave a stressful talk at a university last week) and thought maybe a lot of usual drop ins to this site might not anymore. So, in the title for today, am reaching out to a new demographic: persons interested in congealed soil matter. They might later, after stopping by, discover a new interest; that in clouds, pretty ones. Most of the cheap tricks I try like this don’t have any effect, though. Oh, well.
Let us go forward after backing up:
But the Cirrus kept coming and more odd sights were seen:
Heavier Cirrus, increasing and lowering to Altostratus finished off the day as a heavy shield of middle and upper clouds raced toward southern Arizona from the Pacific:
“Due to time constraints, we move ahead in the action…”
Sunday, November 5th:
4:26 PM. Perhaps the brightest example of iridescence I have ever seen! Just spectacular for a few seconds in this patch of Cirrocumulus. Iridescence is caused by diffraction around the tiny of droplets, less than 10 microns in diameter, as are present when a cloud just forms.
As here, just to reinforce that assertion a bit. Its a link to a recent blog by my cloud-obsessed friend and author, Maria Mudd Ruth. I strongly recommend buying a few of her books. Really, I do!
But in viewing our deep blue skies, pocked with little fluffy Cumulus clouds over the past two or three days, you would not need convincing that even tiny clouds are beguiling, a wonderful attribute for a planet to have. Having mountains on a planet is great, too, and watching the interplay of clouds and their shadows on them is a never ending pleasure. We’re pretty lucky when you think about it to be on a planet like this one. Hope you think so, too.
No rain ahead, glumly, though some sprinkles are out there this morning as frontal cloud band passes over. Just a little too high off the ground for real rain. And the cloud tops aren’t quite cold enough to form much ice, too. Those cloud tops get colder going to the NE, and so higher terrain up thataway (e.g., Show Low) are getting some light rain this morning. Right now, there’s a little sprinkle just beyond Romero Canyon, so we got a little ice this morning in them clouds.
What was interesting is that I never saw no ice yesterday, to continue the slang of rock and roll, in another cheap attempt to reach out to another demographic. The clouds were just a bit too warm for ice-formation, tops running in the -4°C to -5°C range according to yesterday afternoon’s Banner University of Arizona’s balloon sounding. Some may have bulged up to nearly -10°C, but still not quite there. I looked constantly for signs of ice and never saw none, and neither did you, of course.
Bases were cool, at about 4°C, at 11, 000 feet above sea level, or 8,000 feet above Catalina. Tops, about 15,000 feet above sea level. So, they were running around 3,000-4,000 feet thick with no ice. This was a situation where dropping dry ice into those clouds would have created snowfall, then sprinkles, that would not have fallen naturally. Doubtful anything would have reached the ground anywhere near our elevation, however, but up at Ms. Mt. Lemmon, something would have likely even measured from doing that far enough upwind.
In summary, yes, there are some fairly rare times you can get some precip out of clouds by seeding them and yesterday was one of them1.
Today the clouds are thicker, drop sizes therefore larger in those tops of a cloud band similar to the one we had yesterday evening. As drop sizes increase, the temperature at which they freeze also increases. Well, at least that’s what we found over and over again at the U of Washington.
The result, some ice has formed even though they’re hardly colder than just -9°C or -10°C (14°F). Check the radar:
Here are some cloud shots from the past couple of days. Should be some more great scenes today:
Due to time constraints, we now move ahead in the action. Well, its not really “action” is it?
Well, not that much, just a day ahead….
Moving ahead to yesterday and the day long cloud band….
What about the haze? Where’s it coming from and its awful! And its here again today. Reminds one who lived in southern California of summer skies in southern California, hazy, whitish, the orange- colored sunsets that people sometimes thought were “so pretty” but they were ugly because they were orange because of smoke and smog and s like that.
Where’s it coming from, to repeat? Not sure. But see back trajectories below.
These suggest its coming from the east in the last day or so of the trajectories. The trajectories start high up because we’re in the descending air branch of an upper air anti-cyclone that’s dessicating the air, preventing even little baby Cumulus from forming.
Lidia’s moisture will help some, but it appears no rain will reach us today, Dang.
But things get more promising for at least a short return of the summer rain season (remember, the real monsoon is in India) in the immediate days ahead, phrasingly vague enough to insure a great forecast verfication! haha
Looks across Catalina and Oro Valley toward the Twin Peaks area yesterday afternoon. “Egad”, to repeat a mild expletive.
The orangy colors denote the strongest winds in “Jetty Jetstream”, and as you know, the colder, low clouds, ones capable of reaching the temperatures where ice forms, are contained within that ring of strongest winds at this level (500 mb). So, while the models I have looked at so far have no rain here, I think there’s a pretty good chance of a rogue shower tomorrow morning anyway. At least there should be some nice Stratocumulus/Cumulus tomorrow and some will have ice in them. As you know, it’ll be awful windy today, too, maybe 40 mph or so in brief gusts here in The Heights of Sutherland.
Also will be looking for some nice lenticulars since “Jetty” will be right over us, but a little toward the warm side where lenticulars mostly occur.
In the meantime, spaghetti suggests a big trough in our area again about nine days from now. The later ACTUAL model outputs don’t show much of anything. What’s up with that? I’m hanging with spaghetti that later model runs will indicate a strong trough, and at LEAST another pulse of cooler air, and another minor chance of rain as we are going to see today and especially tomorrow as when become within the “ring of winds” aloft. Didn’t Johnny Cash sing something about that? Maybe it was Wall of Voodoo…
Below, some spaghetti for you showing a big trough over Arizona and the Great Basin which is not much reflected in the actual models, as noted. But, just watch my friend, how those model outputs will change to reflect a bigger trough about this time!
I thought you’d like to read this (Peru’s Niño), forwarded to me by Niño expert, Nate M. Pretty incredible to read about what is happening down there in the wake of the Big Niño of 2015-16, which really turned out to be more of a couch potato in terms of weather production in the Great SW.
But, all this winter, along the Equator near the coast of South America, there has been something we used to call an “El Niño”, but is downplayed or ignored these days because of a new definition that seemed to explain more weather when it occurred, “Region 3.4” a large zone along the Equator WAY out in the Pacific rather than something near the South American coast (that zone now called, “Regions 1 and 2”), as nicely illustrated by NOAA here.
But what has been the effect of what we might call the “Classic Niño”, a warm strip of water along the South American coast, one that doesn’t extend too far into the Pacific? “Read all about it”, as they used to say. Its pretty remarkable.
And here’s what the SST field looks like. Its boiling down there off South America! (Speaking figuratively, of course):
Peru’s Niño can be thought of as a “classic Niño”, the ones written about in the decades before about 1990 or so when the definition of what constituted a NIño (or Niña) was expanded and delineated more sharply among several definitions that were floating around. We ended up focusing on a region WAY out in the Pacific Ocean called, “Region 3.4” that SEEMED to explain more over the prior years.
What’s so interesting about this is that the “Classic Niño” has been underway pretty much all this winter, and we’ve had, especially in California, a classic Niño response; that is, abnormally heavy precip farther down the West Coast that no one anticipated.
Well, the correlations with Cal precip and “classic Niño” occurrences will take a huge jump upward after THIS winter!
End of Statement (hand-waving) on Niñoes.
Local weather statement: for immediate release
Cooler, fluctuating weather foretold here for that latter part of March, I don’t know how many weeks ago, is on the doorstep after the long, anomalously hot dry spell. Poor wildflowers have been suffering, too, fading, looking a little stunted after a great beginning, one rivaling the great displays of 2010.
All of the local weatherfolk are on top of this now, and so no point recasting that stuff. HECK, you can go to Weather Underground1 and get as “good as can be” forecast for Catalina (Sutherland Heights) out to ten days! And, there’s nothing worse for a weather forecaster with forecasting in his blood, than to be excited about an “incoming” and when you mention it to a neighbor he replies, “Yeah, I heard about that already. Supposed to get a quarter of an inch.” There is no air whatsoever in the “balloon” after that. So, if you have a weather-centric friend who says something about the upcoming weather, pretend that you haven’t heard about it yet, “DON’T say something as hurtful, as “Yeah, I heard about that already.”
So, here, we go the long route because most weatherfolk are afraid to go too far into the future because its often WRONG. Our models tend to lie a lot after about even a week, so only the brave go out even ten days!
However, here, we go out as much as two weeks and more because its not a truly professional site but rather want to get something out there earlier than other people, sometimes called a “scoop” in the news and weather business. That’s why our motto here is, “Right or wrong, you heard it here first!” Furthermore, if a longer range forecast posted here is WRONG, you won’t hear about it anymore!
Cloud maven person will say this about the first incoming of several fronts: comes in early Thursday morning, its strong! Rainfall potential: 10% chance of less than 0.12 inches, 10% chance of more than 0.75 inches. Best of those is the average, or about 0.4350 inches in this one. It has great POTENTIAL to be a soaker, but mods have been all over the place; hence, the large range of potential amounts. At least some measurable rain seems to be in the bag, a paper one please, because plastic is insidious. Note, CMP’s forecast is more generous than that found in WU’s latest forecast for Catalinaland.
The weather WAY ahead, unprofessionally so
Let us look beyond the professional forecasting limits to April:
We know we got several storms/fronts zipping across AZ as March goes out like a lion, but what about April?
Looks like that pattern will continue into April with temperatures below normal for the first part. The end of the unprofessional forecasting portion of this blog, though we do have our NOAA spaghetti to hang our umbrella on…. Check it out for about two weeks ahead.
Some clouds recent clouds, including a couple from yesterday
———————– 1Although “Weather Underground” might sound like an org has a radical origin, maybe something left over from the late 1960s, this particular one was NOT formed by 60s “weatherman” terrorists like Bill Ayers and Bernadine Dohrn (the link is for those of you who may have set trash cans on fire, as happened at San Jose State to protest the Vietnam War, to look back at those days in horror or nostalgia; take your pick) , but rather by genuine weather geeks (haha, I count myself among them, those that can’t get enough of weather, there can never be too much, like the guys mentioned in this “Cloud City” article.)
Doesn’t look promising for much rain here in Catalina in March, however. No rain in sight through the next 10 days at least.
Let’s check our 7 inches with what’s happening upwind, say, in CALIFORNIA, and see if there’s been any drought relief there, through February, via the CNRFC:
As you are likely to know from many media stories last year, Cal was in a drought siege of five straight years, with but got a little relief last year in the northern part thanks to help from the giant Niño, one of the strongest ever.
Alas, it was one that failed to deliver as the big rain producer for the south half of Cal and the SW in general as was expected.
In case you’ve forgotten how bad things were in Cal, let us look back at what was being said, those horrific appearing drought maps, and also how hopeful were were at the time that the Big Niño would take a bit bite out of drought. This is a really good article:
Then, when the Big Niño faded away like maple syrup on a stack of buckwheat pancakes last spring and summer, we were surely doomed for more dry years. And, for a time, the dreaded cold tongue of water in the eastern equatorial region, the so-called, La Niña, started to develop, which would be no help at all for a good rain season like a Big Niño is, usually.
The Niña faded away, too, to nothing as the winter went on, so we really didn’t have much going on in the tropical Pacific to help us figure out what kind of winter rainfall regime we were going to have om 2016-17. Not having anything going on meant winter rainfall could go either way, a difficult to figure out situation for season forecasters.
In retrospect it is pretty astounding how big a signal must have been out there SOMEWHERE that this winter was going to be one for the history books on the West Coast in general, and in particular, for Californians. Californians saw their drought chewed up and spit out in a single winter, including snow packs so high the height of some mountain peaks have been revised. (I’m kidding.)
No one saw such an astounding winter coming.
This winter sure makes one think of the QBO (Quasi-biennenial Oscillation, one up there in the Stratosphere where there’s almost no air (haha, well, practically none)… Did the QBO have a role in this astounding winter; was there a delay in the effects of the Big Niño even without a bunch of convection in the eastern Pac tropics? Doesn’t seem that could be right…
But, William “Bill” Lau, U of Maryland scientist, reported some statistical evidence of such a lag way back in ’88 due to a QBO connection of some kind and ENSO, no physical cause could be discerned, however, not yet, anyway. Lau, 1988, is reprised below for readers who want to go deep: