Its been this way for quite a while, actually since the big rains of late January, but I only found out about it yesterday: “Thousands Gather Under Cloudy Skies for Beach Fun at Catalina State River and Beach Park !” (if one were writing a newspaper headline). See below.
2:40 PM. Here, dozens of kiddies are seen frolicking in the water of the Sutherland River at Catalina State Park.2:44 PM. Soft Cumulonimbus capillatus and calvus turrets line the distant SW horizon while hundreds frolic in sand and water at Cat State Park.2:46 PM. “Ricky” (real name, “Parikit”), who also happened to work in the SAME lab office as the writer for a few years, prepares his daughter for the popular beach activity of sand castle construction.
Before reaching the beach at the State Park, saw some luxuriant spring undergrowth among the trees, and a nice Cumulus turret, one that went on to grow up and be a weak Cumulonimbus:
1:51 PM. Typical of the lush grasses along the Birding Trail at Cat State Park, also due to the generous January rains.2:21 PM. Nice. Altocumulus clouds (upper left) lurk around a Cumulus congestus turret over the Catalinas.3:36 PM. A remarkably summer-like sky, Cumulus congestus in the foreground, Cumulonimbus capillatus cloud lining the SW horizon. Temperature, 70 F.
The weather ahead, as you and I both hope it will be
Been a lot of phony storms in the 10-15 day range indicated by the WRF-GOOFUS model, ones presented here with regularity, then ended up jilting us. So, today when the Canadian model came up with an appreciable rain pattern for AZ in only SIX days, Feb. 21, it was time to exult, switch models, and climb back up on the blog saddle:
Valid at 5 PM AST, Saturday, February 21st. Based on the global observations taken at 5 PM last evening. AZ covered in rain!
What’s even better in this map is that the rain has only begun on the 21st. As you can see, the bunching of the contours off the Cal and Oregon coasts and west of the center of the low, upper left panel, tells you immediately that more rain would be ahead for us if this configuration is correct. That’s because the low will propagate southward, and closer to us, not move off in some untoward direction with a stronger wind field on the back side than on the front (east) side. Also, in a pattern resembling the Greek letter, “Omega1“ as we have in the eastern Pacific and West, lows like to nest in the SE corner of the “Omega”, getting cutoff, stagnant, out of the main jet stream flow, all of which prolongs bad weather in that sector of an “Omega” (here in the SW US). So, lots to be optimistic about today. Strong support in spaghetti for this Omega pattern, too.
Now I haven’t looked at the US WRF-GFS model based on the same obs because it might have something different, a storm that’s not as good as the Canadian one, and I don’t want to know about it. Still feel pretty hurt by the big storm presentations for AZ that weren’t very sincere in that model. And, as we know, sincerity is mandatory in a relationship, even one with weather maps.
And, will there be a tornado today, too? Arcus cloud almost a certainty. Get cameras ready! Read on…farther down.
4 (FOUR!) inches at Park Tank, Reddington Pass area by 6 AM ! Incredible for so early in the storm! Check more totals out from your friendly Pima County ALERT regional gauges. Mods on track to verify those huge amounts that were predicted the day before yesterday! Washes will be running! Flowers happy! I’m happy! Lot of excitement here! ! !
Only 0.15 inches here in Sutherland Heights/Catalina…. so far (6 AM). :{
Yesterday’s study in gray
Today!
Some excitement just now, after seeing that a major rain band had passed by, and we’re now in a break in the rain.
Will it rain more? Tune in at 11 to find out….. (hahahaha; we don’t do that here! More excitement.)
Went to U of AZ mod run from 11 PM AST last night, the very latest, then saw that a narrow, heavy band or precip, maybe a squall line, something out of the Midwest, was foretold for us Catalinans this afternoon!
Then went to examine upper air and positioning of vorticity maximums ejecting out of our incoming trough (vorticity maximums represented by redness in the plot below from the University of Washington’s Weather Department– color scheme by Mark Albright, the color man up there:
Positioning of “red curly air” (vorticity or rotational areas) in the atmosphere at 1 PM AST today, looking for the cause of the afternoon rainband. The approach of red curly air is accompanied by upward motion in the atmosphere. When I looked at this, I exploded with a “yikes!”. more excitement, today’s theme.
This was exciting due to incoming “red curly air” this afternoon above us, AND, due to those spreading out of the contours over us (see arrowhead). Diffluent contours are indicative of air spreading out aloft, something that leads to enhanced upward motion.
And, to blab on, the air aloft will be cooling off on top of our high-for-winter dewpoint air (50s), which should lead to large Cumulonimbus clouds, likely organized in a line of thunderstorms, as all this happens this afternoon or evening.
And, going over the edge here some, as is my wont, we might well see a funnel cloud somewhere today. This is the kind of situation that you can get them. So, to sum up today:
Possible funnels! Will they reach the ground somewhere in AZ? Maybe. Lightning! Hail likely, too! Rain rates likely to reach an inch an hour, though that rate may not last an hour unless you’re real lucky and get shafted real good.
Will be watching intensely for all these manner of things today! Haven’t been this excited since Oct 2nd, 2010, I think it was when they had that tornado in PHX!
Remember, too, our motto:
Right or wrong, you might have heard it here first!
The weather way ahead
While a long spell of dry weather comes after this 2 day event, the mods have popped up with a heavy dose of rain in two weeks. Of course, normally this would be considered Fantasy 101. HOWEVER, a slight amount of credibility is added when such a pattern that brings rain strongly resembles the one you have now. Check out these upper level flow maps out, as rendered by IPS MeteoStar, that has just moved their pay wall to March from February (yay!). The first one below is for today’s situation, and the second one for Valentine’s Day in two weeks. Look pretty similar don’t they.
You see, weather has a memory like your horse. You ride to Deer Camp way up in the Catalinas; you’ve never been there before, nor has horsey, and then you head back, but you’re not sure of the way.
Well, horsey will remember for you!
(To continue with the extra excitement theme of today’s blog!)
Well, the weather has a memory that we call “persistence”, likes to do the same thing over and over for awhile, and so when a similar pattern turns up in the models that you have now, we give it a little more credibility than none when its two weeks out, maybe 30% chance of actually happening (i. e., still a bit of a long shot).
Here’s what we have today; low off Baja spinning moist air from the far southern latitudes into AZ.Valid at 5 AM AST, February 14th, Valentine’s DayThe big rain accompanying the Valentine’s Day Storm.
Actually, there are no thoughts about the Super Bowl here. The title was just another cheap attempt to attract a reader that might be both cloud-centric AND a football fan, creating a moneyful increase in web traffic for this blog.
First you had your Cirrus, the highest of all clouds except for stratospheric nacreous clouds which kind of mess things up up there by eating ozone. We will not display n-clouds.
Cirrus, as you know, ALMOST always precedes lower clouds since they’re moving so much faster than the lower ones. So we get a sequence of clouds before it starts to rain that generally is the same, over and over again as in that movie about weather, Ground Hog Day. But let us ramble on…
First, patchy Cirrus, then maybe a sheet of Cirrostratus, then the lower stuff as Cirrostratus thickens downward to become that gray sheet called Altostratus. Throw in a few Altocumulus clouds that become a sheet underneath, and voila, your in Seattle, with rain on the doorstep. Yep, that’s the Seattle, and well, the Middle Latitude Pre-Storm Cloud Sequence (MLPSCS)2.
7:41 AM. Birds on the wire, waiting for the storm, notice the invading Cirrostratus fibratus. Low smog plume moves NW out of TUS and into Marana again (at very bottom of image).
10:49 AM. What a fine example of Cirrus spissatus (Cis spis) trailing larger ice crystals, certainly these would be “bullet rosettes”, looking something like a cholla bud, except the spines that stick out all over in this type of ice crystal look like hexagonal columns radiating out of a tiny center crystal. The ones NOT falling out are likely stubby solid columns, plates, prisms, and “germs”, the latter not really germs, but tiny, amorphous ice crystals not having grown a particular shape yet, all too small to have appreciable fallspeeds like the bullet rosettes. A whole sheet of this cloud having so much ice falling out would constitute what we would call, “Altostratus”, gray and deep.
11:46 AM. Another interesting scene. Are these Cirrus clouds spreading out, or is it perspective? Note bank of thick Cirrus on the horizon, too. (I think they were actually spreading out some.)12:49 PM. Here comes the next lower layer, Altocumulus clouds. However, note that ice formed in or just above this layer of Altocumulus, indicating that although it is one comprised of droplets (liquid) it is VERY cold. What is your next thought? HTCs (High Temperature Contrails) or “APIPs”, where aircraft that fly through them seed them by producing huge numbers of ice crystals due to extra cooling provided by over the wing flow, jet exhaust water producing extreme supersaturations, or prop tip cooling. Cause hasn’t been quite nailed down, but cooling is the leading suspect where the air is cooled to -40 C or so, and ice has to form in moist conditions.2:26 PM. With the Altocumulus and Cirrocumulus displays came periods of iridescence in the clouds, indicating tiny droplets less than 10 microns in diameter. There were more grandiose displays, but they were so gaudy my photos looked fake.
4:04 PM. Out ahead of the invading sheet of Altocumulus were these CIrrocumulus clouds with a cool herring bone pattern (“undulatus”). While called, “Cirrocumulus”, these clouds were actually at the same level as the invading Altocumulus clouds shown in the next photo. Its the fineness of the granulation that makes us refer to them as “Cc” clouds, even when they are in the middle levels, and not truly high clouds as the prefix “Cirro” would suggest.
4:09 PM. The invading sheet of Altocumulus perlucidus translucidus (no shading, honey-comb, flocculent pattern). On the horizon, Seattle-like solid veil of Cirrostratus, something that’s pretty rare here. This was an exciting scene because of the advancing layers, the darkening on the horizon, in the context of the major rain ahead.4:17 PM. You have to have ice in your veins if this shot doesn’t give you goose bumps. So pretty, all that uniform flocculation3 up there in Altocumulus perlucidus translucidus.4:24 PM. I can feel that you want more flocculation…
4:31 PM. Maybe just one more… Feeling pretty great now now that I’ve flocculated you so many times today. Three or four is about my limit.5:08 PM. APIP line, or HTC (“High Temperature Contrail”)–ones not supposed to occur at the temperature of this Altocumulus perlucidus translucidus, but they do anyway. Last evening’s TUS sounding pinned this layer at -24 C (-11 F!). Note that no other ice can be seen falling from these very cold clouds. The “castellanus” appearance of a contrail is extremely unusual, and may indicate a sharp decline in temperature at the level the aircraft flew. However, then it begs the question about why the Ac clouds aren’t turreted, at least, SOME. You’ll probably have to take CM’s word that its an ice trail. Note indication of a hole in the droplet cloud at far left of trail. That’s a clue.5:08 PM. To the southwest and west, layers of Altocumulus, some having turrets, and with a beautiful veil of CIrrostratus above, advance on Catalina. I love shots like this, though sans color, due to their rainy portent, even though our rain is not supposed to being for another 24 h, or this evening.
The weather just ahead
Of course, everyone, including media weathercasters, are all over the incoming stupendous storm event. For a more technical discussion, here’s one by Mike L., U of AZ forecasting expert, who got excited enough about our storm to come to send out a global e-mail. I think you should read it, though I left out all the graphics. I’ve already been too graphic today.
———–Special Statement by Mike L———————————-
“A very unusual heavy precipitation event is forecast for the next few days across Arizona and New Mexico as extremely moist air interacts with multiple short waves. As seen in the below data from the NWS, the maximum monthly IPW for Jan is about 28-29mm. If the various WRF forecasts verify, the upcoming storm will set new a new January IPW record.
The 12z WRFGFS indicates very high moisture levels being advected towards Arizona due to a low latitude low located west of the Baja spur. While IPW has slowly decreased from the previous storm over much of the area, La Paz is seeing a upturn in observed IPW.
As seen below, at 5pm today, some convection is forecast near to the low. Lightning data has indicated there has been some strong convection during the day today. Model initializations are normally suspect so far from any upper air stations, but it seems that both the NAM and GFS seem to have the intensity and location initialized well. One item of note is that during the past few days, the models have had a trend of moving the heaviest precipitation back to the west. Initially, the heaviest band was well in to NM whereas you’ll see later, it is now over much of eastern/central Arizona.
By late tomorrow afternoon, the low has only moved eastward slightly, but IPW continues to increase over NW Mexico and into Arizona. Precipitation begins mainly over the higher terrain of eastern Arizona.
By Wednesday morning, the mid level low has intensified as a strong short wave dives down behind the mean trough along with CAA into the back side.
Significant synoptic scale lift is present over southern Arizona and into northern Mexico by this time.
Extreme IPW is forecast to be present during the morning hours on Friday and combined with the favorable dynamics, widespread moderate to heavy rain is predicted. As the low becomes cut off, there will be an extended period for precipitation.
Precipitation rates are forecast to be above .25″/hour in some locations during the morning hours.
Partial clearing is forecast by Friday afternoon which allows some heating. Combined with cooler air aloft and high IPW, moderate amounts of CAPE are present during the afternoon.
By later in the afternoon, as Bob Maddox pointed out, convection forms and results in some locally heavy precipitation.
Tucson’s vertical profile is quite impressive with 700 J/Kg of CAPE and some vertical shear to support organized convection. Hail is also a threat.
Convection continues into the evening over southern Arizona with a continued threat of hail and some lightning.
The 3 day QPF is very impressive with widespread 1 inch amounts with some areas receiving over 3 inches. Some of these areas are associated with the strong convection present on Friday afternoon/evening. Confidence is low to medium due to the lack of upper air data and lack of run to run consistency as discussed previously. Also, the output in this discussion was solely from the 12z WRFGFS. The WRFNAM from last night had the heaviest precipitation somewhat to the east. It will be informative to see the next suite of model runs overnight to see if this westward trend ceases. There is a chance that it could continue and the heaviest precipitation is actually farther west than depicted below.
Very little of this precipitation falls as snow except at the very highest elevations, above 9k feet due to the sub tropical air-mass and lack of cold air.
Note that this discussion will only be available for organizations who are (or have) supported the Arizona Regional Modeling Program. This change will take effect before next monsoon season. Private individuals not associated with commercial/governmental agencies will continue to receive the discussions. If your agency would like to support the Program, please email me for details. “
————–End of special statement by Mike L—————————
The End!
1Let us not forget Simon and Garfunkel’s telling descriptions of Patterns of life; they repeat in clouds, too. (Pretty funny lead in commercial where Bryant Gumbel is asking, “What is the internet?”)
2Back in the old days when cloud forms were used to tell weather, Cirrostratus sheets, those high thin sheets, often with a halo, foretold rain 70% of the time here in the US (see Compendium of Meteorology, 1951). Deserts don’t much see this sequence. Cirrus are mostly meaningless in them, just indicating some withering tail of a system with rain that’s far away most of the time.
1) The quarter inch predicted/hoped for here fell on Borrego Springs, CA, (0.27 inches) instead. So, it was pretty close. We received a measly trace in the past 24 until we got 0.05 inches just now! Barely made the 0.05 inches, thought to be the least that could fall. So, in humility, will be expanding limits of storms, maybe go with 0-5 inches possible amounts for every next storm. Should hit those.
2) Mods still think more rain is ahead over the next few days, beginning on Thursday. This period of rain has always been predicted to be more than yesterday anyway.
3) As an outstanding weather note for my reader, I thought I would post this photo from a friend in Seattle of the exceptionally warm weather for this time of year they had yesterday in Seattle (60s). A young1 woman at Green Lake in Seattle displays how warm it is by dawning a bikini, near where the present writer used to live. “Smells like global warming”, as Seattle’s own Kurt Cobain1 might have said about yesterday, if he wasn’t dead.
While there have been studies about cherry blossoms and that kind of thing coming out earlier in the spring back East of late, maybe there should be one about bikinis coming out earlier, too. How many weeks earlier in spring than during the Little Ice Age, do we see bikinis nowadays? How long has the bikini season been lengthened? Is it commensurate with lengthening of the growing season? That would be a VERY interesting scientific question to address, one that needs to be fully addressed via graphs and photo documentation. Applying for NSF global warming grant monies now…..
Yesterday afternoon at Green Lake in Seattle. A young woman dawns a bikini! Unheard of in January in Seattle! Thought I would display this full size so that you could see how warm it is. Thanks to Bob S, Ballard District, for supplying this datum.
Yesterday’s clouds
8:31 AM. Rainband encroaches from the south horizon. Flow was from the southeast, but movement of band was to the north. The clouds in the foreground are two layers of Altocumulus. The banded rain cloud moving toward us would be Nimbostratus.11:30 AM. Dammitall, its still not here, and now the rain coming out of the band is so slight you can see through to the other side! Nice birds of some kind on the wires, upper left. Makes me think of that Leonard Cohen song, Bird on the Wire, best interpreted by Judy Collins, of course.
11:31 AM. Lotta birds on the wire. I thought you should see this. Above, Altocumulus/Stratocumulus, with a higher layer of Altostratus.4:08 PM. After the trace and clearing, a new bank of Altocumulus/Stratocumulus and rain band approached from the south. Virga can be seen on the horizon, too. Hope building again for measurable rain.4:19 PM. From the corral, a display of Altocumulus/Stratocumulus lenticulars downstream from the Catalinas. Nice lighting on hills, too.4:30 PM. Cloud maven juniors should have noticed that the lower layer of clouds here (left of center), are LOWER than the clouds that passed over earlier. That means the incoming rainband had a better chance of producing measurable rain though it didn’t.4:40 PM. Another great sign that measurable rain was on the doorstep though it didn’t were these faint Cumulonimbus tops showing up beyond Pusch Ridge. Gettin’ excited here, as you were no doubt. Some pretty hard radar cells came up out of Mexico then.
That’s it. No more photos, no rain last night, either, but in some kind of rain miracle, it has just put 0.05 inches in the gauge! So, the forecast from this typewriter that 0.05 inches was the least that could occur in this “storm” has been verified!
Conditions not ripe for much more, though a few light showers are still upwind. Clouds oughta thin as the morning goes along, with huge breaks in the clouds this afternoon.
Mods suggest more rain beginning as early as Thursday night. This one has more potential for rain here, somewhere between 0 and 5 inches, i. e., only a 10% chance of less than zero; less than 10% chance of more than 5 inches. There, that should do it….
The End
———
Composer, lead singer for that Seattle band, Nirvana. You can see Kurt in a cloud of smoke singing, “Smells like air pressure here“, a Bill Nye parody of the true Nirvana hit where Cobain sings in a lot of smoke, “Smells like teen spirit.” Compare versions.
7:20 AM. Altostratus with pouches of virga7:23 AM. Ditto. Ac len is the fine line cloud upper center.7:27 AM. Ditto, pretty much.7:30 AM. Nice lighting (not lightning) for just a few seconds.8:19 AM. Altocumulus trailing snow/virga. Tops, though the coldest part of the cloud, are composed of mostly of droplets at temperatures far below freezing. A few ice crystals form and drop out leaving the supercooled droplet cloud mostly intact.
12:55 PM. Just about the first boundary layer cloud, this a Cumulus fractus fragment. Hope you recorded this event in your cloud diary. Its pretty mandatory to note developments like this if you want to move on to the next level of cloud-mavenhood.
3:03 PM. Those boundary layer clouds, Cumulus ones, were reaching their maximum depth about this time. This would be a Cumulus mediocris, estimated depth 2500 feet or so.5:14 PM. Whilst clouds locally never got beyond the “mediocre” stage, or produced ice under them, to the north where the air was colder aloft, Cumulus clouds were able to grow taller and become Cumulonimbus capillatus (hairy looking with ice) incus (the last term just meaning it has a flat anvil, a flat head.)
5:47 PM. This post sunset shot shows layers/lines of smog at the same level where some flat Cumulus remains are. The smog is so visible because the air is ALMOST saturated near those clouds at their level, and some of the smog particles (hygroscopic ones) have deliquesced, have gotten much larger by absorbing water vapor, or might even be haze droplets where water has condensed on them (“smoglets”). It therefore, by definition, cannot be a “pretty sunset.”
The model rain ahead; two episodes
The low that plunks down off the coast of Baja this weekend from southern California, circles around out there for a couple of days, before deciding to move back over southern California with clouds and rain. If it was a song, it would be The Wanderer. Yes, that fits. Its expected to scoop up a generous helping of middle and high clouds from the deep tropics as extra baggage. The “extra baggage” (model predicted rain) arrives here late on the 26th (Monday) and continues off and on through Tuesday night. The first clouds, of course, high ones like Cirrus, will begin arriving a day ahead of the actual rain, on Sunday.
It is virtually certain that there will be some high-based Cumulonimbus clouds and thunderstorms in these masses from the tropics, though maybe not here. Most of the rain is projected for eastern California and western Arizona where rain is really needed–and how great is that?
However, we should be in for a quarter inch or so, anyway. Last time I guessed limits on a storm, even the lower limit of 10% chance of less than 0.05 inches wasn’t even realized. Pretty pathetic forecast. But, moving forward and forgetting past errors, this one seems to have a similar range of possibilities, the least amount 0.05 inches, the most, 0.50 inches. The chance of measurable rain here in Catalina in this first 36 h storm period is probably, from this typewriter, about 80%.
“But wait! There’s more!” “Maybe!”
A second system floats in right after that and from Jan 29th through early in Feb, and more welcomed showers are possible.
You can check out these prognostications in a more professional way at IPS MeteoStar, this link to the latest model run from 11 PM AST last evening.
Wednesdays here in Catalinaland are, of course, trash and recycling days. And, along with T and R day, we found ourselves amidst some pretty pretty scenes, and in some cases, extraordinary ones,….and a little rain (a trace here in The Heights). I reprise those scenes in case you missed them; you probably did because you’re not some kind of photonut like the writer.
However, be advised that some of the mid-day photos will show smog, smog that was ingested into our poor clouds.
That smog bank, emitted from the Tucson area, almost reached Catalina yesterday during the day. It came up around Pusch Ridge and up along the west side of Samaniego Ridge and almost reached Catalina before its advance was halted by a north wind push and it retreated to the the south. My heart was beating so fast that it might overrun us! Marana and Oro Valley were heavily contaminated for awhile. And smog is like a cloud cancer1.
7:46 AM. A rare display of Stratus along the Tortolita Mountains. If you were hiking and were in this, it would be fog to you, still Stratus to me viewing it.7:46 AM. Rare shot of what appears to be ground fog or just fog rolling eastward out of Tucson. Some flakes of Altocumulus above, and a higher layer of Stratus on the Tucson Mountains.
8:49 AM. This was an amazing sight, to see a thin Stratus cloud fronting an early morning Cumulonimbus capillatus. The Stratus is hard to see, but its the thin dark line on the horizon above Priscilla’s house below the turrets and ice of the Cb. The only other time I have seen such a sight was in Seattle after a snow with Stratus clouds and fog all around the city, but with warm Puget Sound sending up plumes of big Cumulus clouds.
10:37 AM. The day was not without some cloud levity, as these “twin tower” Cumulus clouds show, drawing attention to themselves.
11:26 AM. First ice in clouds becomes visible. It was obvious a few minutes later, but if you saw at this time, or can find it here, you are a pretty CMJ, worthy of an accolade. Of course, if you looked at a radar map of the area, you would have known where to look in advance since there was a small echo in this complex by this time. The precip just was not enough to form a shaft. Note, as well, that Twin Peaks, Continental Ranch area is NOT visible due to the smog bank that was going to move up this way, as it turned out. And look how gorgeous it is toward the Tortolita Mountains!
11:38 AM. OK, here the ice from that turret in the prior photo is now obvious (center frizzy area). However, it was also obvious that the smog toward Marana/Continental Ranch was now closer, even while we had a north wind here in Catalina. Was that southwest wind going to win and mess up our fantastic skies?11:42 AM. Here you can see the smog as it was advancing around Push Ridge and had gotten farther north along the side of Samaniego Ridge. Those lower cloud fragments along Pusch Ridge at the top of the smog tell you that the air was more moist than the air our Cumulus clouds were forming in, and therefore, that this advancing smog bank likely associated with deliquesced aerosols from cars and other urban effluents (aka, “air sewage”) accumulated during the Tucson fog earlier that morning that was now being mixed into a deeper layer and heading this way! To think of breathing air like that. in a short while..it was a ghastly thought.
12:12 PM. To make a short story long, the advance of the smog, with its lower based clouds got as far as Golder Ranch Drive over there by Samaniego Ridge (whitish area below the lowest cloud base on the left), before receding under a freshet of north wind. However, some southern parts of Catalina were affected for a short time.
1:14 PM. By this time, larger complexes of Cumulonimbus clouds, pretty weak ones, were developing over and north of the Tortolita Mountains and upstream of us offering the hope of some measurable rain in Catalina, the smog pretty much pushed back to the southern parts or Oro Valley and Marana.
2:00 PM. Widespread light rain showers were in progress from these weak Cumulonimbus clouds, but sadly, bypassing Catalina. But huge visual payoffs were ahead as the clouds broke at times, and some stunning sights emerged.
2:35 PM. Stunning….to me, anyway. View this in full screen mode for best impact. Later, more accessible stunning.
3:01 PM. Breathtaking; in total awe of this scene! Note gliaciated tower at right.
4:28 PM. And those scenes just kept coming! It was hard to be indoors for even a minute.
5:28 PM. The fading sunlight and the fading Cu only got more breathtaking. And we realize how lucky we are to be here and see scenes like this so often.
5:38 PM. The smog belt, held at bay during the day, still lurked to the SW of us, compromising our sunset by providing a reddish-yellowish sickening hue to it, a sign of a smoky presence, that may compromise today if we’re unlucky.
The weather ahead and way ahead
Well, RIP El Niño, an EN expert has written me just yesterday. Not much left of it he says, having a attached a map of ocean temperature anomalies to kind of rub it in. So we can’t count on hot water in the eastern Pacific to help fuel Southwest storms as was expected by the CPC and others last spring. But, that doesn’t mean that there can’t be a juicy late winter and spring, but the odds are down.
And, we won’t see clouds like yesterday until the long-foretold-by- spaghetti trough arrives around the 22nd of January, and with it some chance of rain. Doesn’t look like it could possibly be very much. BTW, Only 0.02 inches total in three days of light showers in the current situation. :{
BUT…..in the longer term, spaghetti is once again HINTING at a break-on-through-to-the-other side situation, your writer’s favorite as a kid, 10-14 days from now. A high builds up along the West Coast and in the eastern Pacific, gets too big for its britches, can’t maintain its giant north-south range, drifts farther and farther north and begins to break up, kind of looking like a horseshoe with the open end down (toward the south) as the jet stream “breaks on through to the other side” and “underneath”, that being a jet stream comes through from the warm subtropical central Pacific to the southern areas of the West Coast.
The north part of the West Coast and Gulf of Alaska are dominated by higher pressure with lower pressure to the south, so its kind of an upside-down-from-normal looking weather map, pretty rare, and that’s why its cherished by yours truly.
The End, at last!
—————————————————-
1As you know, when clouds are heavily contaminated with air pollution, they can’t rain as easily because the droplets are smaller inhibiting rain in two ways: by preventing the formation of drizzle and rain drops, and making it more difficult for ice to form since the formation of ice happens at higher temperatures when cloud droplets are larger. So, clouds have to be taller when they are polluted to produce rain, either way.
It doesn’t get much better than this plot below for our Catalina weather 10-13 days ahead, which is always pretty fuzzy-looking as a rule. “Better” means for rain chances here, which is not everyone’s “better.”
Here’s the excitement:
Note blank area, that is, an area free of lines area centered on the gambling and other mischief-permitting State of Nevada1.
Note how the red lines dip down into Mexico, whilst the blue lines bulge northward into Canada along the West Coast.
This error-filled plot2 tells us that it is almost certain that a trough will be in the lower middle latitudes where we are on January 22nd or so. Just about guaranteed.
In the meantime, those blue lines indicated that a ridge of high pressure is going to divert northern storms into Canada and southeast Alaska. Sometimes we refer to situations like this as “split flow”; the southern portions of storms in the Pacific move ESE toward southern California and the Southwest, while the northern portions split off to the NE, as is happening now. Weak upper level disturbances pass overhead, the next one tomorrow, and with it, a little more rain, the models say.
U of AZ mod has rain moving in toward dawn tomorrow with totals here amounting to about like that last rain, 0.10 to 0. 25 inches. Given model vagaries, probably the lower and upper limits here are likely to be 0.05 (worst case scenario) and 0.50 inches (best case scenario), so a best guess would be the middle of those, 0.275 inches, not too much different from the AZ mod. This is the sports-like part of weather forecasting. What’s your estimate, fantasy or otherwise?
BTW, there were quite a few stations reporting over an inch of rain in Santa Barbara and Ventura Counties during the past 24 h, and so while weak, this system is pretty juicy, lots of liquid water as measured by dewpoints which should rise into the upper 40s to low 50s here during the next day. Also, there have been some embedded weak Cumulonimbus clouds and that’s a possibility here tomorrow, too, as the rainband goes by. You’ll be able to tell that by strong shafting below the clouds. As always, hoping we here in Catalina get shafted tomorrow.
But the ones these days are weak, while the split ahead in 10-13 days is likely to contain much stronger disturbances, well, at least ONE before it gives out.
Yesterday’s clouds
7:22 AM. Sunrise Altocumulus.
11:42 AM. Another very summer-like looking day with clouds beginning to pile ever higher over the Catalinas.
12:51 PM. Small Cumulus are developing over the Catalinas while far above them are, two crossing contrails, about the same age suggesting that aircraft crossed paths simultaneously. The FAA flight separation rules now allows for 1,000 feet of separation instead of the 2,000 feet in years past, and so if you’ve flown recently, you may have noticed planes that appeared to be a lot closer to you than ones a few years ago. This has been permitted due to improvements in aircraft GPS accuracy, and was deemed needed due to the vast increases in air traffic in the decades ahead. Still, there were times when opposite flying aircraft were so CLOSE, passing by like bullets, that you wanted to scream to the pilot, “Hey, wake up and smell the air space!!!!”
1:44 PM. Probably had a little ice in that smooth section, but overall really looked like a miniature summer Cumulonimbus cloud. Did not see if it had an echo, and never was it clear that there was ice.2:02 PM. As Altocumulus castellanus overspread the sky, lenticular clouds were still visible beyond the Catalinas. Some lenticulars began to sprout turrets, an odditity, but one driven by the condensation of water, something that releases a little heat (in this case) to the atmosphere causing the cloud to be more buoyant.
5:32 PM. A sunset of Cirrus and Altocumulus. Not bad.
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1What a great and honest state motto that would be! “Nevada: That US State where gambling and other social mischief is OK with us!”
2Don’t forget that due to growth in computer capabilities, we can now have many model runs from the same data and be done with them in a timely way. These “spaghetti”, “ensemble” or better yet, “Lorenz” plots are computer model runs with deliberate (!) slight errors introduced to see how the model forecasts of high and low pressure centers changes, given a few slight errors. This is because there are ALWAYS errors in the data anyway, there are always error bars on measurements, etc. By doing this, only the strongest signals in the forecasts remain, indicated by grouping of lines these two colors of lines, red and bluish. So, the forecast of the jet stream coming out of Asia is very, very reliable. Things go to HELL, downstream (toward the east), but some likely patterns can still be seen, such as the one over the Southwest US where a trough/low is almost certain in our area then. Will it bring us rain in Catalina? Hell, I don’t know because if the trough is a little too far to the east of us, we might only get cooler. However, since Cloud Maven person has a postive rain bias, he will say, “Absolutely. There will be rain in the Catalina area on January 22nd or so”–the actual timing might be off by a day or so.
It was a great day to hike to that wash, too. Began with a nice sunrise; missed the nice sunset, darn. Hope you didn’t.
But the highlight of the day was seeing that water was still running in the Sutherland Wash, some eight days after our great snow. Like so many things that happen to meteorologists, I didn’t expect it.
Your cloud day yesterday
Was an interesting day because at times it looked summer-like due to Cumulus formations over the high terrain, Kit Peak to the Catalinas. The scenes below are mainly from a hike1 out to some native rock etchings.
7:22 AM. Sunrise Altocumulus.10:38 AM. Petting zoo. I wanted to hop on this cow and ride it so bad! It seemed so docile. Wanted to just how riding a cow would feel like, have a new life experience. Didn’t seem to mind the several of us going by.10:42 AM. Glinting rocks through the Tucson smog layer. Yep, it rounded the corner and trucked on up along the Catalinas, kind of like our Stratus fractus does on some days. Mixed out later, of course, as Cumulus clouds ate some of it.
11:07 AM. Its always so special to see water in our washes. This scene just due east of the “brown house” and before the “Rusty Gate” heading up the east side of the hills. Pretty regular equestrian crossing point. The water was gone some few hundred yards farther downstream.12:09 PM. Nice display of Altocumulus perlucidus, while the summer-like scenes began to emerge. Note the Cumulus congestus forming over Kit Peak on the horizon, center. Pretty exciting to think of summer already!12:53 PM. This pretty summer-like scene out there on the trail just behind the Old Lloyd Golder Ranch. The small Cumulus clouds were even streaming off from the S and SSE just like they do so often in the summer! There are some Altocumulus perlucidus clouds above them.The grasses along the washes are already a few inches high! Nice to see that green coming along so well after 3.82 inches of rain in December (rainlog total that assigns the 7 AM measurement to the prior day since 0.96 inches was measured on Jan 1. Usually its put on the day of the measurement.)12:31 PM. Due to the wetness, Seattle-like mosses are beginning to appear. Got a little homesick there for a second. Expect mushroom hunting to be a big tourist industry later this winter in Arizona as more storms line up for us.2:23 PM. Cumulus pile up into the Altocumulus layer above, helping to enhance it. Didn’t see any ice or sign of precip coming out of these clouds, though was watching closely as I am sure you all were, too, for a “first ice of the day” report in your cloud diary.
Detecting ice module below. I hope most of you logged this as your first ice sighting of the day.
4:08 PM. Whilst scouring horizon to horizon, saw this gem at last: ice! What, you can’t see the ice? Too far away? See the following photo for zoomed version.4:08 PM. Zoomed shot of glaciating complex of Cumulus, some virga, light rainshower below it. Still can’t make it out? See next shot with annotation.Tops, from TUS sounding perhaps briefly as cold as -12 C before subsiding to lower, warmer levels. Almost certainly a case of “ice enhancement” or “ice multiplication”, a situation where there are many more ice crystals in a cloud than can be accounted for by ice nuclei, solid substances on which ice crystals form.
While waiting for still more rain, The End.
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1Two of the people I was hiking with are very important meteorologists; faculty members at big universities with big Ph Ds, Wikipedia pages, give lectures all around the world about what they know. While I myself am not important, if you can align yourself with important people, befriend them in some way, and then go on to tell your friends that you have befriended that kind of person and do things with them, YOUR own mediocre life seems greatly enhanced. Let us not forget the guiding words to a peaceful, successful life as told to us in “Deteriorata.”
From yesterday’s 18 Z, or 11 AM AST WRF-GFS model, this behemoth. Seems to be reaching up to grab something! Millions of square miles affected! This is the SAME giant storm you saw predicted in an earlier prog and displayed here yesterday from the prior evening’s run, just more ominous-looking here in the run some 18 h later. Will it happen? Comes and goes in the mod runs, but “spaghetti” hedges it to happen, at least some rain.
Valid on January 21st, at 11 PM AST. Regions of color denote those areas where the model has calculated that precipitation has fallen during the prior 12 h.
In the meantime, we received 0.09 inches here in Catalina/Sutherland Heights last evening, another shot of rain, with more little systems like that one predicted to affect us during the coming week. If you were watching, you saw that you could see blue sky on the NW horizon while it rained steadily, most of the day to our S. Go here to get the Pima County ALERT totals, the greatest about a quarter to a third of an inch.
Cloud bases were pretty high all day, around 11,000 feet above sea level (8,000 to 9,000 feet above ground level). Some boring photos:
1:31 PM. A rain band from mid-level clouds makes it way slowly northward toward Catalina. Altocumulus opacus to the north of the raining cloud; the precipitating cloud farther south is Nimbostratus (few know that the official cloud folk label “Nimbostratus” as a middle level cloud).Winds blasting out of a strong high pressure center in Texas pushed into Tucson, pushing the “usual” city effluent west and northwest into portions of southern Marana and the Continental Ranch development where snowbird and iconoclast climatologist, Mark Albright lives. Today’s word game is, say “iconoclast climatologist” three times as fast as you can.5:11 PM. Both sides of this cloud mass were visible near sunset, the clearing to the northwest beyond the virga can be seen here on the horizon while at the same time to the SSW, you could see the clearing on the south side. Really thought the chances of measurable rain here had ended at that time, but maybe, since 0.09 inches fell later in the evening its not good to say that, make you lose confidence in the things you read here.
The total was likely more, but at 3:30 AM it was 1.5 to 2 inches in the deepest spots, and likely had melted down to those levels overnight. One report, down Swan and Golder Ranch Dr way, was 3 inches on a deck after midnight! And its so pretty with all the Christmas lights around!
What a great rain and snow storm, too! It fell so gently, and at the same rate, R- to R– (“light rain”, and “very light rain”, as we used to code it) for a total of at least 0.59 inches–some snow in the gauge has to melt before the final total is known. While it seems a little high, the Bridge at Golder Ranch Drive and the CDO wash is reporting 0.98 inches!
Here’s the unusually steady way that our rain/snow fell. Normally a storm system is composed of “rainbands” with higher intensities, and lower intensities, or even no rain in between them (see Elliott and Hovind, 1964, Journal of Applied Meteorology) if you think I made that up for some reason.
All of the high gauges had snow, and the snow has clogged the gauge so that there are a lot of bogus zero or tiny amounts in our mountains. It would appear that the liquid water totals will be an inch or more when its all melted and gone into the gauges today.
Yesterday’s fast moving middle and high clouds; about 100-120 mph with delicate patterns
In case you don’t believe me, here is the text version of the TUS sounding at 5 AM AST, yesterday morning, December 31st, last year. I thought maybe seeing some numbers would do you some good. Remember what Lord Kelvin said: “He whose knowledge cannot be expressed in numbers has but a meager, insufficient kind.”
Also, Kelvin-Helmholtz waves1 are named after the famous physicist; the surfers at The Mavericks, and other big wave locations like to see giant K-H waves roll in and break.
72274 TUS Tucson Observations at 12Z 31 Dec 2014
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PRES HGHT TEMP DWPT RELH MIXR DRCT SKNT THTA THTE THTV
hPa m C C % g/kg deg knot K K K
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Begin 100 mph winds at these levels (444 mb, and 6525 meters) where the Altocumulus/Cirrocumulus were and over 120 mph where the Cirrus was (289 mb, and 9551 meters). The “82”in the first line is the wind speed in knots, which is 100 mph.
OK, images being corrupted again as they are imported into Word Press, something that started a few days ago. You can see the corruption by the linear shadings in these first two photos
Quitting here. This is pretty frustrating when you put in so much work trying to be silly, but at the same time also want to have great, and interesting photos!
May resume blog someday when this problem is fixed.
Just cold ahead for the next 24-48 h followed by a nice warming trend. No rain now in sight over the next two weeks, outside of a few mountain snow flurries tomorrow. “Trough Bowl” seems to be shifting eastward, which means repeated cold snaps east of the Rockies. It be replaced by a humping ridge over us, something that means the storm track is bumped up to the Pac NW and northern Cal.
The End
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1K-H waves:
Taken by the author a long time ago at Seattle’s Sandoval Park.
