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.6:17 PM.
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! 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. 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.” 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, 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 Bio25:16 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.
Welcome to one of the great cloud blogs of our time today, great as in volume, not in eloquence or anything like that.
6:16 AM. Pink castellanus, Altocumulus castellanus. Note the “micro-cumulonimbus” turret complete with a little anvil that’s shearing off to the left (center left). So now what? Should we have a cloud called an Altocumulonimbus? Maybe so, since on this morning, clusters of Altocumulus grew into major true Cumulonimbus clouds with rain and lightning in Arizona yesterday morning. Its a pretty common thing having thunderstorms and Altocumulus castellanus and floccus based at the same level at the same time.6:21 AM. Looking pretty much at the same scene but a little farther to the north where a dissipated Cumulonimbus can be seen (on the right) formed at the same level of the Ac cas, in case you didn’t believe me that that could happen.6:43 AM. Rainbow and corral, horse poop in foreground. Yours today for only $1800. Shows that aforementioned Cumulonimbus was producing rain to the ground. Was the first rainbow event of the day.12:08 PM. While Ac cas and small Cumulonimbus clouds dominated the sky all morning, heating finally started to launch boundary layer clouds fueled by that heating. With lower than normal temperatures aloft due to an upper level trough, watch out! Here we go!12:13 PM. Hardly had the thought to “watch out” crossed my mind, when I looked up toward Winkelman and Mammoth areas and saw that it was too late to “watch out” as this gargantuan Cumulonimbus had already exploded up thataway.1:23 PM. A large Cumulonimbus erupts upwind of Catalina. Will it make it? Because this is a fall circulation pattern with a tough in the westerlies affecting us, the clouds are moving more rapidly than usual and from the southwest, not from the eastern semicircle, our as during our normal “summer rain regime.” Remember, the “monsoon” is in India and all around there.2:21 PM. OK, its an hour later, that distant Cb didn’t make it but this one upwind looks more promising. Why? Because its got a protruding Cumulus base on the left side suggesting it will keep developing. Same on the right side. Without those re-inforcements to the updraft of this complex, it would die, all or most of the rain fall out before it got here. Let’s see what happens.2:31 PM. Starts to look disappointing again, but hope arises in the distance. See caption-sized note on photo.2:43 PM. I could feel your excitement here as the farther out base developed, broadened, new shafts started to appear in the distance from that complex of firm-looking bases. I was excited too. Maybe we’d get half an inch out of this group!2:44 PM. In the meantime, nice lighting on the Catalinas and moderate Cumulus pass by in a hurry. Thought for today: “Mountains: the canvases on which clouds paint.”3:03 PM. Heart has sunk by this time, as did yours. New cloud bases (on the left side) driven by outflow winds is causing this thunderstorm to propagating to the right of the wind flow and so the part of this that appeared to be directly upwind of us, and looked so good, was now raining out because there was no new cloud forming to keep it going in a steady state way So, no half inch after all except maybe down there. Oh, me. Nice scene, though.4:21 PM. Break in the action. This Cumulus congestus cloud person seems happy, thumb is pointing up. Not so much here as upwind clouds have dwindled.5:13 PM. THen, just after it looked like it was over, and cloud maven person left his post, all HECK broke loose as a powerful thunderstorm roared out of the Tortolita Mountains and off toward Oracle and points north. The shaft that fell out has produced a small arcus cloud, that lower scruff ahead of it. That was to be our hope. A blast out of the north from this monster that could trigger overhead new cloud developments!
\
5:15 PM. Unnecessary close up of this monster.5:20 PM. Another look at the dramatic sideswiping storm. Looks more like a shot from Kansas or OK.5:20 PM. In the meantime a blast of north wind from the giant cell north of us has hit Sutherland Heights and is pushing up a great looking base that is creeping TOWARD us!5:21 PM. Its only a minute later, but its such a great, dramatic scene its worth checking again.5:23 PM. That great cloud base just north of Sutherland Heights is starting to unload, but it hasn’t progressed farther south. Hmmmm.5:29 PM. The north wind was accompanied by a scruff of clouds that topped Samananiego Peak. But what’s wrong here? Look at the poor “quality” of the cloud base over and just east of us now, full of light and dark areas, not a solid blob of darkness as we saw just to the north of us. So, this is going to do nothing here.5:31 PM. That low cloud continues to race south, and with the sun breaking through, produced a pretty scene if a depressing one due to the lack of a “good” big, dark base.5:32 PM. That large, dark cloud base has receded to the north while scud clouds still stream south. Dang.5:39 PM. That great Kansas-looking storm is disappearing now behind Pusch Ridge with only the middle portion of the cloud left to precipitate (once have a great bottom, one that disappeared as the shove upward went to the east. So, its still thick and low enough on the right side to produce a burst of moderate rain, but will it get here?5:45 PM. Remarkably heavy rain still falls out of clouds that now appear to be only residual Altocumulus/Altostratus (cumulonimbogenitus, of course). And, if you saw this scene, you could anticipate being in somebody’s rainbow when the sunlight got to you, and that you were going to see something special in that regard VERY soon.5:47 PM. Yes, but two minutes later, the sunlight reached Sutherland Heights causing this rainbow spectacle.5:48 PM. Another look at this spectacle. There appears to be a pinkish red drop, maybe a part of the rainbow I have to be in for others to the west of me! Real evidence maybe of being in a rainbow when your in the rain and the sun is shining! Never have seen a pink drop before.5:49 PM. Let’s look and see if there is another end to this rainbow… Yes! There it is toward Charouleau Gap.5:50 PM. Close up of a rainbow to see what it looks like a little better.6:44 PM.6:43 PM. Stratocumulus of the evening.
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.
This was amazing. I approach one of the puddles on Equestrian Trail. I see that its raining HARD in the puddle. I am only 20 feet from it, but its not raining on my car! Here’s what that scene looked like:
3:26 PM. Equestrian Trail road puddle outbound from Sutherland Heights.
How could this be? Of course, we’ve all seen heavy rain on the road and drove into it. But the illusion here that was so striking is that it only SEEMED to be raining in the puddle, not around it since the drop splashes were not obvious as I drove up to it.
The rest of yesterday was pretty great, too, lots of rainbows, brilliant clouds and skies, too photogenic for a neurotic-compulsive photographer. However, one of 221 photos was of a human, a neighbor, not of clouds and rain shafts.
Here are a few too many cloud photos; excess is kind of a specialty of mine:
6:25 AM.6:25 AM.
6:25 AM. Unloading.6:26 AM.
7:40 AM.11:58 AM. Cumulonimbus cloud boils upward upwind of Catalina.12:25 PM. Getting closer….12:51 PM. Lightning strikes not that close…Hail up to pea size, though.1:10 PM. Backside of storm looked pretty good, too, quite firm and protuberant, indicating updraft still intact. Note whitish fallstreak, likely graupel and or hail.1:10 PM. Horse exults over extra rain.1:43 PM. Crepuscular rays due to rain, not haze. A pretty scene sez me.2:18 PM. Another dramatic scene.2:36 PM. Biosphere 2 hit by light rainbow.2:42 PM. For the sharp-eyed, bit of arcus cloud below Cumulus bases shows the northwest wind and cold front about to hit Catalina. Hit over there by Marana first. Was minutes away here.2:46 PM. Something akin to an arcus cloud is just about on Catalina. Remember, the shift of the wind precedes the cloud, and lifts the air above it. Did you notice how the whole sky began to fill in with clouds as the windshift hit and for the hours after that? Pretty cool, huh?3:56 PM. Awful dark out for this time of day. And yet another rainbow! Is this Hawaii, or WHAT? Rainbow colors end where snow is falling, not rain.
4:05 PM. Day closes with more storms drifting toward Catalina.
Lightly looking ahead
Still a lot of “troughy” weather ahead, and chance for decent November rains in the first half of the month after cold one goes by, followed by a short dry spell.
6:25 AM. Altocumulus perlucidus. According to my cloud chart, informally known as “America’s Cloud Chart”, it could rain within 6 to 196 hours. Its quite useful.10:24 AM. Altocumulus opacus. Note the rumpled look of the sky. Indicates that the clouds are rather shallow and composed of droplets rather than a mix of ice crystals and droplets. However, if you strain your eyeballs and look to the horizon, you can see a smoothing and a little virga showing that the cloud tops are rising and they’ve gotten cold enough to produce ice. According to my cloud chart, when you see “Ac opacus” it could rain within 6 to 196 hours.1:44 PM. While the clouds are pretty much the same gray color as in the prior photo, they’re much thicker here and are “Altostratus opacus”. “opacus” because the sun’s position is not visible, though it wouldn’t be in this direction anyway, but to the right. The bottom of this is smooth due to widespread, light falling snow, though it not in a localized area enough to be called virga in this shot. The lack of bunched or heavy virga somewhere tells you that the cloud tops are pretty smooth, too, not a lot of variation in height. The base is really determined by the point that you descend out of this precip, in this case up around 10 kft above the ground over Catalina.4:12 PM. Altostratus opacus praecipitatio or Nimbostratus, either name will do. Recall the quirk in our cloud naming system that makes, “Nimbostratus” a middle-level cloud. The base of these clouds is the general level where the snow falling out has evaporated. Due to bulging tops, and stronger updrafts, a little of the precip was able to fall out because the snowflakes coming out the bottom had grown larger and were able to survive the dry air below cloud base.
Some rain fell about this time in Catalina. Not enough to darken the pavement completely at any time. The main thing to take away from that hour of very light rain is that it was not “drizzle” as even some errant meteorologists call such sprinkles.
You will be permanently banned from attending any future meetings of the cloud maven club if you refer to such rain as we had yesterday afternoon as “drizzle.” Drizzle is fine (200-500 micron in diameter drops that are very close together and practically float in the air. Because they fall so slowly, and are so small to begin with, you can’t have drizzle at the ground from clouds that are much more than a 1000 feet or so above the ground because as soon as they pop out the bottom, those drops start evaporating and fall slower and slower by the second, and in no time they can be gone even in moist conditions. That’ s why its somewhat hilarious and sad at the same time, when, in particular, military sites for some unknown reason, report ersatz “drizzle: (coded as L, or L-) in our hourly aviation reports from clouds that are based at 5000 feet or something CRAZY like that.
This band of Nimbostratus/Altostratus had a backside that approached as the sun went down, and as you know, that clearing let some sunlight enrich and dramatize the views of our beloved Catalina Mountains:
5:39 PM.5:41 PM.
Finally, dessert:
5:47 PM. Rainbow lands on the University of Arizona Wildcat’s Skycenter atop Ms. Mt. Sara Lemmon.5:48 PM.
The amazing rains ahead
Nothing that you don’t already know about, so no use me blabbing about it too much. But in case you haven’t seen it, The Return of Joe Low (after over-hydrating over the warm waters of the eastern Pacific), is expected over the next couple of days, with a little help from another disturbance, to bring colossal rains to eastern Arizona and especially New Mexico.
Below, from our friendly U of A Wildcat Weather Department a model run from yesterday’s 5 PM global data (the Wildcat’s downsize the US WRF-GFS model in this awesome depiction).
Check out the totals expected by the evening of October 23 rd. Stupendous. Usually these totals are a bit overdone, but even so…… Will take a nice bite out of drought.
Precipitation totals expected by 5 PM AST October 23rd. Looks something like a tie-dyed Tee.
in Sutherland Heights, that is. but 1.58 inches (!) over there by Tangerine and Oracle Road:
Personal weather station rainfall totals as of 7 AM AST this morning. All of these totals are for the period after midnight last night! The green and yellow regions are rain areas from the TUS radar.
Yesterday’s clouds; pretty spectacular stuff
2:42 PM. Out of focus hailstone. Thought you’d like to see that first.
The remainder of the photos were taken at various times during the day, except as noted:
2:49 PM. Dwarf rainbow due to the high altitude of the sun.2:49 PM. Dwarf rainbow with a larger view of backyard letting go to HELL, not doing anything with it, or, as we would say, is a “restoration of habitat combined with erosion control project in progress (Letting nettle grass takeover, too.) Its great being environmental and lazy at the same time! Hahahaha, sort of. Originally this recovering area was scrapped off for a new septic system. Is in recovery now. Yay!
At 0.77 inches, and only 0.01 inches yesterday, Sutherland Heights is running a little behind our July rainfall average amount for the 13th of about an inch. But, we had an “above average”, really quite spectacular, long-lasting rainbow yesterday. Hope you caught it.
6:40 PM. Rain on mountains, sun breaking through. Get camera ready.6:43 PM.6:46 PM. Cam lens not wide enough to capture full glory of scene. Would never be as good as in real life, anyway.
6:47 PM. Lingered for about 15 min, too.
U of AZ mod run from 06Z (11 PM AST) calculates that today and tomorrow will be active late afternoon and evening thunderstorm days.
Hurricane Diary: Just formed Dolores just reaching hurricane stage today, winds of 65 mph or more. But, up, up, up, they will go!
This first one grumbled a bit, sent a bolt or two earthward last evening. Dropped a quarter inch on Ms. Lemmon. Hope you caught these brief scenes from two modest Cumulonimbus clouds:
7:05 PM.7:05 PM.7:31 PM. A different, very modest Cumulonimbus cloud that’s almost totally composed of ice (from this view). Note how the orange of the cloud is seen in some solar panels in the foreground. Pretty neat. Eyeball top, upper 20s, temp -20s.
Spurred from hibernation by these scenes somewhat like the flying ants we have around here by a good rain , AND by the amount of rain indicated in SE Arizona in the latest model run, the one based on the 5 PM AST global data. Here’s what happens in that run:
A tropical storm (what is likely to have been a Category 4 or 5 hurricane earlier in its lifetime) whizzes offshore of Baja in in 11 days or so, rather unusual for July, and lassos a humongous amount of clouds and rain, dragging them Arizonaward.
Here are the ark-like outputs from our best model, the “WRF-GFS”, as brought to you by IPS MeteoStar.
Rains move in on the night of the 19th-20th. This output showing the 12 h rain areas ending at 5 AM on the 19th.
The panels below are for every 12 h after the one above.
These heavy rains just go on and on, about three days worth in that run. Have NEVER seen so much rain predicted for this area, and while its too far away to have much confidence in it, its still worth considering as a possible event. You might want to perform some leak checks around the house just in case.
While the rainfall predicted above is somewhat moot, the likelihood of a strong hurricane in the Mexican Pacific is almost assured by our ensemble model runs (spaghetti plots). The signal is strong for one to form down there. Really, this kind of forecast is a remarkable thing that our models can do now days!
Such a hurricane will be fueled by the continuing extraordinary and vast areas of sea surface temperature anomalies; the entire eastern Pacific is aflame in unusually warm water. Check it out:
Sea surface temperature anomalies as of yesterday, July 9th.
As far as today’s weather goes, well, you can see those thin low clouds topping Ms. Lemmon this morning. Dewpoints continue high, around 60 F. And with a trough moving in, should be another breezy, pretty day with scattered Cumulonimbus clouds.
But, for a man’s forecast, not a little wispy one like the one above, see Bob’s site for an outstanding analysis! CMP (Cloud Maven Person) does not have the time to do a good, thorough one, if he could.
In fact, the chance of MEASURABLE rain in Catalina is at least 100%, maybe as high as 300%, between 5 AM AST, Sunday, March 1st and 5 AM, AST, March 4th. Namely, its gonna happen.
Now, its not gonna rain that whole time, likely starting later in the day on the 1st. Pretty darn exciting to have a sure thing in the future! Check out this 4-panel presentation of maps from Enviro Can, I really like them:
Valid for Monday, March 2nd. Heavy rains foretold in western AZ by this time. Likely will be here by this time, too, though THIS model thinks the rain is still to the west.
Perhaps going farther than one reasonably should, the likely minimum amount will be 0.33 inches (10% chance of less) and top amount, gee, this situation has a big top, 1.50 inches, due to this trough’s deep reach into the sub-tropics, meaning it could pulling extra wet air toward us if everything works out in the “best” possible scenario. The best guess, between these two extremes is the average, or about 0.9 inches during our rainy spell. Should keep the washes flowing, though this one being colder than January’s tropical rains, should pile up lots of snow on top of Ms. Lemmon, so
Moving ahead to yesterday……
A pretty nice 0.09 inches fell yesterday morning in The Heights. “Nice”, because some model runs a few days in advance of this had no rain as a dry cold front went by.
When did the cold front pass?
9 AM yesterday, marked by a freshet from the NW with gusts to maybe 20 mph, with a falling temperature. Fell from 51 F to 42.x F by mid-morning, snow down to about 5,000 feet on Samaniego Ridge, too, though it melted almost immediately.
A push of wind like that virtually always builds a cloud above it, and yesterday was no exception. Here’ the cloud associated with that “freshet”:
8:31 AM. Wind shift line cloud shows up NW-NE of Catalina. Get ready!8:32 AM. Mini-rainbow appeared for just a moment.8:34 AM. Tiny holes in clouds produce pretty highlights on Eagle Crest as the windshift line cloud approaches.8:34 AM. Ditto above.9:03 AM. Windshift and line cloud pass over Sutherland Heights. Starting to rain here, though very little.9:03 AM. Close up of the bottom of the windshift line cloud.12:39 PM Post frontal passage quiet time with flattened clouds.1:28 PM/ Clouds swell up, first ice seen. Can you find it? More to north at this time.2:24 PM. Lots of pretty cloud “streets”, Cumulus clouds aligned in a line. Here’s a common one coming at you, one that comes off the Tortolita Mountains on Cumulus formation days with a westerly wind in the boundary layer (the layer between the ground and the tops of these clouds).3:19 PM. Walkin’ dogs now, but spotted trace of ice overhead in that SAME cloud street coming at me from the Tortolitas. Uh-oh. Do you see the trace of ice up there?3:21 PM. Few raindrops beginning to fall. Can you detect that bit of a rain haze on the left of center in this photo, out toward the Torts? Very hard to see, but there was an nearly invisible “shaft.”3:33 PM. Tiny snow shaft hangs from this same cloud line as it began to shift to the south and east. Can you find it?
Of course, the best part of days like yesterday is the play of the light and shadows on our mountains:
5:19 PM.5:58 PM. Stratocumulus clouds above the Charouleau Gap.
When one first encounters this title with its unexpected play on words, we wonder what the author had in mind. Of course, most of us know that at Christmastime, we are often regaled by a Christmas tune called, “Frosty the Snowman1“. But here, we are surprised as we continue reading the title that instead of encountering the word, “snowman,” we encounter the word “Lemmon!” Hah!
What is meant here? What is author trying to tell us? Perhaps the word, “lemon”, has been misspelled. But if so, why would a “lemon” be frosty? Perhaps there was a cold spell in Florida and the author is harkening the reader to a long ago memory. Or, perhaps misspelling “lemon” was a literary device to emphasize that word in an eccentric way.
Yet, upon further investigation, we find that the issue is more complexed than first imagined. We find that there was an art teacher, nurse, and eventually, a self-educated botanist from New England, Sara Plummer Lemmon, who, with her husband and another worker, hiked to the top of the Catalina Mountains right here next to us, and while doing so, they logged the vegetation that was unique to the area. In their excitement when reaching the top, they named that highest peak after Mrs. Lemmon.
So, what does this piece of history add to our literary dilemma encapsulated in the title?
Perhaps Mrs. Lemmon did some work in the field of glaciology as well, hence, the word “frosty” as a possible hint of that work. Yet, upon investigation, we find no mention of work on ice crystals, hoar frost, nor glaciology not only in the work of Mrs. Lemmon, but neither in the work of any the team that mounted what is now known as Mt. Ms. Lemmon. We add that the note that the Lemmons, J. G. and Sara, were on their honeymoon at this time, historians tell us. Perhaps there is another avenue we can explore due to that latter element.
Could it be, too, that we are missing a characterization of Ms. Lemmon by our author? Perhaps she was shy, seen inadvertentlhy as “cold” by some, or was not particularly interested in the physical advances of her husband, J. G. The word “frosty” alert may be alerting us those possibilities.
Ultimately, we remain perplexed by this title; it forms an enigma that may never be confidently resolved.
But then good titles, and good books, are supposed to make us think, try to imagine what the author is telling us through his/her use of metaphor and other literary devices, and this title has done that.
We, of course, reject the most plausible, superficial explanation, that the author’s play on words was merely describing a local, snow and rimed-tree mountain named after Ms. Mt. Lemmon, as in the photo below. No, Occam’s Razor, the idea that the simplest explanation is usually the best one, will not do.
4:43 PM. Those trees are rimed, like the airframe of an aircraft that collects drops that freeze and cause icing. Here the wind blowing across the mountain top, and cloud droplets that were below freezing, hit the trees and froze over a period of many hours, creating this scene. Its not snow resting on the branches. That would’ve blowed off in the strong winds up there.
———End of Literary Criticism Parody Module———-
There was a rousing 0.24 inches of rain yesterday! Our storm total has topped out at 0.89 inches!
In other photos from yesterday:
9:42 AM. Altostratus translucidus again, with a few scattered Altocumulus cloud flakes, but this time with bulging Stratocumulus topping Samaniego Ridge, giving portent of a good Cumulus day if the As clouds will only depart and allow a LITTLE warmth. They did.
10:24 AM. Before long, cloud bases darkened here and there, indicating mounding tops above a general layer, and with the low freezing level of about 7,000 feet, the formation of ice and precip was not far behind.10:51 AM. Mountain obscuring showers were soon in progress due to both a little warming, but also because of a cloud energizing swirl in the upper atmosphere that passed over us at 1 PM AST. Did you notice that windshift aloft as that bend in the winds went by up there? You probably noticed that it was no dice, er, no ice, after 1 PM as the mash down of air that follows “troughs” did that very effectively after 1 PM.
10:52 AM. As the clouds (weak Cumulonimbus ones) broke, there was a fantastic rainbow for just a seconds to the north, landing on my neighbor’s house. It was even better before this, but was slow getting to the camera! Dang.
10:54 AM. “Pictures a poppin’ ” now as breaks in clouds allows those fabulous highlights of glinting rocks and scruffy Stratus fractus or Cumulus fractus clouds lining Sam Ridge, those highlight scenes that we love so much when the storm breaks. And these scenes change by the second, too!
11:00 AM.Also 11 AM. Out of control with camera now…..
11:12 AM. Meanwhile, back upwind… This line of modest Cumulonimbus clouds fronted by a weak shelf cloud roared in across Oro Valley to Catalina. What a great sight this was since now there was a chance of some more decent rains! Before long, the rains pounded down, puddles formed, and another 0.18 inches had been added to our already substantial total of 0.65 inches.
12:01 PM. But that wasn’t the end, was it? Before long, a heavy line of Cumulus and weak Cumulonimbus clouds formed again to the southwest and drenched Catalina with another round of rain, this time, only 0.06 inches. And with it came the End. This line of showers was spurred by that upper level wind shift that was going to occur over the next hour.
1:01 PM. Sometimes those clearing skies, the deep blue accentuating the smaller Cumulus clouds provide our most postcard scenes of the great life we have here in the desert.2:13 PM. While it was sad looking for ice in the afternoon clouds and finding none, the scenes themselves buoyed one. The instability was great enough that even brief pileus cap clouds were seen on top of our Cu.2:21 PM. Pileus cap cloud (right turret) tops honest-to-goodness December Cumulus congestus cloud. No ice nowhere.
2:28 PM. And if the sky and mountains splendor isn’t enough for you, then consider our blazing fall-winter vegetation as evidenced by a cottonwood tree in the Sutherland Wash,’ that yellow dot, lower center. We have it ALL now!2:48 PM. And, as the cloud tops are kept low, we get those fantastic, quilted, richly colored scenes on our Catalina Mountains we love so much. Here, looking toward Charouleau Gap and Samaniego Peak. I could show you so many more like this from just yesterday!
5:08 PM. Even our lowly regarded teddy bear chollas have luster on days like this, the weak winter sunlight being reflected off its razor-hook-like spines, ones that many of us know too well.
5:12 PM. And like so many of our days here in old Arizony, closed out with a great sunset.
Possibility raised in mods for giant southern Cal floods, maybe some flooding in AZ floods, too
Something in the spaghetti plots has been tantalizing as far as West Coast weather goes. They have been consistently showing a stream of flow from the tropics and sub-tropics, blasting into the West Coast. Recall that yesterday, that tropical flow was so strong and so far south, that at least one major gully washed was shown to pass across central and southern California on New Year’s Day, but weaken and shift to the north of southern AZ after that.
Well, my jaw dropped when this model run from yesterday at 11 AM AST came out, re-enforcing, even raising the bar on flooding, in central and southern California, and with those stronger storms, the possibility of flooding and major winter rains here in Arizona was raised. The severity of the pattern shown aloft is not one I have seen before, and for that reason alone, might be considered somewhat of an outlier prediction, one really not likely to occur.
Now, while there is some support in this model flooding “solution” in the spaghetti plots, the main reason I am going to present a series of what a disastrous Cal flood looks like is just FYI and how it develops. The closest analog to this situation was in January 1969 when a blocking high in the Gulf of Alaska (GOA), forced the major jet stream far south across the central and eastern Pacific on several occasions producing disastrous floods in southern California in particular, where one mountain station received more than 25 inches of rain in ONE DAY!
Also that blocking high in the GOA in Jan 1969 also forced unusually cold air into the Pac NW, where Seattle (SEA-TAC AP) accumulated 21 inches of snow over the month, still a record.
Here we go, in prog maps of our WRF-GFS rendered by IPS MeteoStar:
In the Beginning, the blocking high, shunting the jet stream to the south and to the north takes shape in the GOA. Note low far to the south between Hawaii and southern California. Get sand bags out now! This is for 11 PM AST, 28th of December.
24 h later:
Valid at 11 PM AST 29 December. Southern Cal flooding underway. Cold air pocket in Oregon has slipped southwestward helping to energize the lower band of jet stream winds by bringing cold air out over the ocean. The greater the temperature contrast between the north and the south, the greater the speed of the jet stream between the deep warm air to the south, and the deep cold air to the north. Note, too, high is getting farther out of the way in the Gulf of Alaska.
The situation continues to strengthen, and leads to this Coup de Gras, 11 PM AST January 1st. A system this strong barging into southern Cal is mind-boggling, and this panel is what brought this part of the blog, to show you what a devastating flood in that area would look like:
Valid at 11 PM, January 1st. In my opinion, I doubt the Rose Bowl game between the Oregon Ducks and Florida State would take place in Pasadena, CA, if this were to transpire.
Now for AZ. Here’s the prog for 12 h later, 11 AM AST January 2nd, Cactus Bowl Day in Tempe, AZ between the Washington Huskies and the Oklahoma A&M Aggies, to continue with sport’s notes here. Rain would be expected for that game should this pattern persist:
Valid at 11 AM AST, January 2nd. This is an unbelievably strong wave that has roared in from the lower latitudes of the Pacific. While it rushes through Arizona in a hurry, heavy rains, and some flooding are likely should things transpire like this.
Now for a gee-whiz, scary analog….one from WAY back in the winter of 1861-62 when the situation decribed above was likely very similar to what it was in that terrible flood; severe cold in progress in the Pac NW, as it would be in the upcoming situation; a tropical torrent raging in from the Pacific. This 1861-62 flood episode is still remembered. However, it went on for 30-40 days (!) with recurring episodes turning much of California’s central valley into a lake, Los Angeles area, too, where there was a report of 35 inches of rain in 30 days.
What’s ahead, really?
Well the models are going to fluctuate on the strength of this breakthrough flow “underneath” the blocking high in the Gulf of Alaska. But almost certainly one major rain event will break through as that this happens. Its kind of a fragile flow regime, so it usually doesn’t last long.
Whether it will be stupefyingly historic, or just another ordinary southern Cal gully washer, can’t be pinned down. But, if you lived down there, you’d want to be looking around and seeing what you could do to divert water, fix a roof, etc.
There would be strong, damaging winds with one of these “coming-in-underneath”, too, and, for surfers, giant waves!
Interesting times ahead! “Floodmagedon”, as we like to say these days?
No real weather here for awhile, except around Christmas when a mild cold snap, and a little chance of precip occurs as a cold front goes by.
The End, for awhile.
—————————–
1The most intellectually satisfying version of “Frosty the Snowman” was, of course, has been rendered by Bob Dylan.
Had another rainbow from those cloud “warriors” we call Cumulonimbus on the Catalinas. But, “If traces are your thing, Catalina is king!” as we recorded but a trace of rain again while soaking rains poured down just a couple of miles away on the Catalinas, to form a sentence with too much punctuation and a sentence within a sentence1.
More interesting perhaps to some, this modest rainbow formed just after 5 PM yesterday toward the Charouleau Gap, as seen from Catalina, and was still in almost the same spot after 30 minutes. Have never seen that before since both the sun and the showers are drifting along and so the rainbow should change position.
First, in today’s cloud story, the strangely believe it rainbow part:
5:12 PM. Rainbow first spotted toward the Gap. Cumulonimbus cloud not sporting ice at top; ice is below flat top due to weak updrafts that allow the ice crystals to subside while the top remains mostly liquid appearing. The smoothness on the side of the cloud above the rainbow is due to ice particles5:42 PM. While the observer has moved some few hundred yards, the rainbow has stayed pretty much where it was after 30 min. A course in optics would be required to explain this and that’s not gonna happen (accounting for the sun’s movement, the rain, and the observer’s movement).
The whole day represented several phases, the early, spectacular eruption of clouds on the Catalinas as it started to warm up under clear skies, those low bases topping the mountains again indicating stupendous amounts of water are going to be in them when they grow up, the rapid appearance of “first ice” just after 10 AM, the heavy showers and cooling on the mountains and here (little thunder heard), the clearing due to the cooling, the warming, the rebuilding of the Cu on the mountains, and new showers–the rainbow was part of the second growth phase, and then the gradual die out of the Cu as sunset occurred.
Huh. I just realized that what happened to our temperatures yesterday was like a mini-sequence of the earth’s climate over the past 200,000 years or so, the prior Ice Age in the morning temps, the warm Eemian Interglacial as it warmed up, the last ice age when the cooling wind from the mountain showers hit, then the warm Holocene when the clearing and warming started up again in the afternoon! Cool, warm, cool, warm. Below, the Catalina temperature record that emulates earth’s climate over the past 200,000 years, beginning with next to last “ice age.” I can’t believe how much information I am passing along today! What a day you had yesterday!
Mock climate change for the earth’s past, oh, 200, 000 years or so as indicated in yesterday’s Catalina/Sutherland Heights temperature scale. But, we have a LOT of days like yesterday’s in the summertime, but only now after 7 summers has it hit me how it mimics our earth’s “recent” past climate.
Cloud Alert: Yesterday might have been the last day for summer rain here. U of AZ mod from last night has plenty of storms, but we’re on the edge of the moist plume, and those storms take place just a hair east of us it says. So, while they may be on the Catalinas today, unless we get lucky, they’ll stay over there. Drier air creeps in tomorrow, too.
Here is the rest of our day in clouds, from the beginning, even if its not that interesting. In the interest of efficiency, you’d do a lot better by going to the U of AZ time lapse site to see all the wonderful things that happened yesterday, instead of plunking along one by one as you have to do here. (PS: Some functions in WordPress not working, would not allow some captions to be entered as usual.)
9:21 AM. This tall, thin Cumulus cloud was a reliable portent for yesterday’s early storms on the mountains. It just shot up!
11:57 AM. Thunder and downpours are widespread on the Catalinas.
2:46 PM. After the long clearing, Cumulus begin to arise on the Catalinas again.5:46 PM. A pretty, and isolated Cumulus congestus with a long mostly water plume ejecting toward the NW. Some ice can be seen falling out of that ejecting shelf. Now here’s a situation where an aircraft measuring the ice output from such a cloud can miss it because its formed as the turret subsides downstream, and most of the ice is substantially below its top, and under the shelf. If you cruised along the top of the shelf, you would miss most of the ice and measure ice particle concentrations that are much lower than what the cloud put out.6:17 PM. This same quasi-stationary cloud with its long shelf, still shedding ice just downwind of the cloud stem, is about to disappear. Note, too, that the ice fall quits after awhile going downstream even though cloud top temperature is the same for quite a distance. The ice was actually formed at lower temperatures in the protruding turret, not at the temperature of the shelf, which apparently were too high for ice to form. Also, cloud droplet sizes shrink from those in the protruding turret as evaporation takes a stronger hold. Larger droplet sizes are associated with greater ice formation at a given temperature.6:12 PM. Like aspen leaves in the fall, but every day, our clouds change color as the sunsets. Here’s another memorable site, not only due to the color, but how tall and thin these Cumulus clouds are, showing that the atmosphere was still extremely unstable over the depth of these clouds, probable 2-3 km deep.
The End.
——————————-
1Hahah-these are just a couple of the grammatical gaffes I actually know I’ve done!