Category Archives: Cirrostratus

Cirrostratus, Cirrus clouds, Contrails, Definitions, Spaghetti plots, The weather ahead, The weather WAY ahead (10 days or more)

Spaghetti is back!

December 15, 2014 Art Rangno

Due to some kind of server meltdown, the NOAA spaghetti plots, better, “Lorenz plots” in honor of “Dr. Chaos”, Edward N. Lorenz, the ones my fans¹ like so much, have not been available.

But they’re back today!

But what are they telling us? Gander this for Christmas Day:

Valid at 5 PM AST Christmas Day, December 25 th. I've annotated it especially for you. — Valid at 5 PM AST Christmas Day, December 25th. I’ve annotated it especially for you. The view is one where your looking down at where Santa lives from a big tower. Not all annotations are accurate.

Don’t need to tell you that the weather looks like there’s a good chance of cold and threatening weather for Christmas Day. Big trough implanting itself in the West around then. Maybe those easterners who hogged all the cold air last winter will share some of it this winter. The warmth we had last winter made it bad for horsey with all the fly larvae that survived.

Kind of bored now with the rain immeidately ahead, but only because everybody else is talking about it, too. Its no fun when you don’t have a scoop and you’re just saying things that other people are already saying. Even my brother in North Carolina, who knows nothing about weather, told ME that it was going to rain here on Thursday! How lame is that? Of course, it is true that you won’t here anywhere else that the chance of measurable rain is more than 100% this week in Catalina ; at least I still have that. Tell your friends.

When does it fall? Sometime, maybe multiple times, between Tuesday afternoon and Friday morning. Hahaha, sort of.

Looks like the first trough and weather system will go over on Tuesday through Wednesday, chances of rain then, and yet another colder one on Wednesday night into Thursday. So, 100% chance of measurable rain falling sometime between Tuesday afternoon and Friday morning, probably in several periods of rain. Look for a frosty Lemmon Friday morning.

Predicted amounts from this keyboard? Think the bottom of this several day period of individual rain events will be only a quarter of an inch. Top, could be an inch, if everything falls into place. Canadian mod from 5 PM AST global data yesterday, for now has dried up one of the storms, that on Thursday, the day the USA! model thinks is our best chance for good rains based on the virtually same global data! Of note, the USA model based on 11 PM AST data, has begun to lessen our Thursday storm that bit.

This is the reason that the certainty of measurable rain here in Catalina is spread over such a several day period.

Your cloud day yesterday

Just various forms of Cirrus, most seemingly from old contrails that produced exceptional parhelias (sun dogs, mock suns).

Very contrail-ee sunset, too, as contrail lines advanced from the west. They were likely more than an hour old when they passed over Catalina yesterday.

10:56 AM. Glistening rocks after the rain. Very nice. Cu fractus at moutain tops.

2:36 PM. Nice example of the rare seen Cirrostratus fibratus (has lines in it). Hope you logged it.

3:42 PM. Looks like old contrails to this old eye, resembling CIrrus radiatus. The "radiating" aspect may be due to perspective. — 3:42 PM. Looks like old contrails to this old eye, resembling CIrrus radiatus. The “radiating” aspect may be due to perspective.

3:50 PM. Parhelia lights up in CIrrus. These, due to the high speed of Cirrus movement, only last seconds in thin streamers like these. To get really spectacular optics the crystals up there have to be especially simple, like plates and stubby columns, maybe prisms as well. When aircraft create contrails, there is an excess of ice crystals, far more than occur in natural Cirrus as a rule, and due to that high concentration, can’t grow much and usually stay as simple crystals, not develop complicated forms like bullet rosettes, crystals with stems sticking out every which way.

5:23 PM. Contrail-ee sunset. Pretty, but awful at the same time, since it shows how the natural sky can be impacted by us in our modern lives. You wonder how much of us the earth can take?

The End

—————–

¹Why just recently C-M had a comment from a fan in Lebanon³, that country near Israel, not the one in Ohio²! Said it was warm there now, but normally it rains for days at time in the winter, and gets real cold. You see, the eastern Mediterranean is, climatologically speaking, a trough bowl. Troughs just hang out there a lot, creating something called the “Cypress Low.” Though it only rains in the cool season, October through May, as in Israel, places in Lebanon get 25 -40 inches of rain during that time, and its exciting rain because it almost all falls from Cumulonimbus clouds, many with lightning! C-M is getting pretty excited, since he’s on record as wanting to go Lebanon to study the clouds there! See Lingua Franca article from 1997! He loves those Mediterranean wintertime Cu. Hell, you probably threw it out, so here it is: Lingua Franca _1997. See last sentence. last page. Thanks.

²Speaking of Ohio, who can forget that great 1980s rant against urban sprawl in Ohio by Chrissie Hinds and the Pretenders! Will it happen to Catalina after the road project? An insurance agent told me that Catalina was to be absorbed by Oro Valley after it was completed. Oro Valley says they know nothing about that.

³“Its great when you’re global!”

Altocumulus clouds, Cirrostratus, Definitions, Stratocumulus clouds

Cloudy with Stratocumulus; 0.11 inches in the bucket so far

December 4, 2014 Art Rangno

Here’s your cloud day for yesterday, a fairly complex day for your cloud diary entries:

7:27 AM. Altocu with Cirrostratus above. — 7:27 AM. Looking SW along Equestrian Trail Road; Altocu with Cirrostratus above.

7:45 AM. Altocumulus perlucidus over the Catalinas.

DSC_0003-1 — 12:38 PM. Stratocu begin to move in under the Altocumulus layer.

2:47 PM. Altocu OR, Stratocumulus lenticularis began appearing, suggesting strengthening winds aloft. — 2:47 PM. Altocumulus lenticularis began appearing, suggesting strengthening winds aloft. This was an odd location for such clouds, perhaps responding to uplift ahead of the Catalinas. Haven’t looked at Froude or Richardson numbers, though, to see if this is reasonable hand-waving.

DSC_0011-1 — 3:02 PM. Looking NNW at Stratocu (“the boring”; is State Cloud of Washington, and Oregon, for that matter) with a little Altocu on top.

4:33 PM. Stratocu. Kind of characterized the dull, dark, late afternoon and evening hours.

Intermittent R- to R– expected during the day today. Hoping for a quarter inch (forecast to friends early yesterday morning, 0.225 inches; will be ecstatic if more falls. Latest AZ mod has about that amount here, and over half an inch in the Catalinas. Usually, though, those amounts are on the high side. On the other hand, if the details about where the the rain band shown below are off a bit, we could do far better than the 0.10 to 0.25 inches predicted. Here’s the accumulated precip predicted for today from that model:

Accumulated rain until 10 PM AST tonight from the U of AZ model run at 11 PM AST, the latest. Much needed, nice heavy band of rain across AZ!

Next rain threat continues for the 12th, plus or minus a day.

The End

Altostratus clouds, Cirrocumulus clouds, Cirrostratus, Cirrus clouds, Definitions, Sunsets

Late morning cold slam

April 26, 2014 Art Rangno

Its not a breakfast at a restaurant chain, but a sharp cold front passage later this morning, say between 10 AM and Noon. Should be pretty interesting. Temperature will drop about 10 F in an hour. Expecting/hoping, too, for a little measurable rain with this “FROPA” (frontal passage in weatherspeak). The brisk winds, as they always do, have activated a lot of the nighttime wind detector lights in the neighborhood.

The usual post-frontal clearing in the afternoon and a pretty cool day, maybe 20 F cooler than yesterday afternoon which got to 88 F here in the Heights, the Sutherland ones, that is. Of course, our media weather stars are all over this weather situation, so nothing much to be added here.

Still have plenty of higher ice clouds overhead right now at daybreak, but look for an invasion of Cumulus and Stratocumulus within the couple of hours after daybreak. They should appear first on the Lemmon, topping it, then fill in after that as the cold slam gets closer.

Yesterday’s clouds

The full complement of expected clouds was not really observed yesterday. Missing in action for the most part locally were Altocumulus lenticulars downind of Ms. Lemmon. Cirrocumulus clouds were also pretty much a no show. You can see some of those high lenticular formations that did occur WAY downwind of Ms. Lemmon and the Catalinas if you view the U of AZ Weather Department time lapse movie for yesterday between 11 AM and 1 PM, then another pile of Ac len just at sunset (7:15 PM) in their movie.

Below, what we did see, various varieties of Cirrus, and eventually those thickening to Altostratus ice clouds. And a hole was out there that allowed a brief colorized sunset rather than a gray one.

9:20 AM. Main feature is Cirrus spissatus, with Cirrus fibratus (lines at upper right) and some uncinus (center left) also present.

1:13 PM. Looking at incoming Cirrus to the WSW… More Cirrus spissatus (patches) in the distance with some hooked Cirrus (uncinus) upper center.

1:14 PM. Looking N at the traces of Altocumulus lenticularis clouds (e.g., sliver cloud above road in distance), possible Cirrocumulus top center of photo.

6:21 PM. By this time, the leaden look of Altostratus pretty much dominated the sky; dosen’t look good for sunset color at this point.

7:03 PM. Sunset bloom began as bottom of Altostratus got lit up. Note how similar the cloud bottoms are in this photo compared to the one just above.

7:06 PM. Heavy line of Altostratus with a higher overcast of CIrrostratus adds interest to the fading sunset.

Altocumulus clouds, Altostratus clouds, Cirrostratus, Definitions, Ice optics, Jerome Namias, Sunrise, Sunsets, The weather ahead, The weather WAY ahead (10 days or more)

Pretty cloud day yesterday; storms dead ahead and ahead

December 11, 2013 Art Rangno

In case you missed the pretty sights of yesterday:

7:05 AM. Sunrise on the Altocumulus. Two layers are evident.

8:42 AM. Kind of blasé except for the rarely-seen-in-AZ (faint) halo. Altocumulus with Cirrostratus above.

3:30 PM. Pretty patterns; Altocumulus perlucidus.

4:45 PM. Cirrus uncinus and Altocumulus (clouds with shading). — 4:45 PM. Cirrus fibratus (not hooked or tufted at top) and Altocumulus (droplet clouds at right with darker shading). Lower gray portions beyond Pusch Ridge and extending to the horizon is probably best termed Altostratus.

4:56 PM. Nice lighting effects on Samaniego Ridge. — 4:56 PM. Nice lighting on Samaniego Ridge.

5:21 PM. Your sunset. Nice underlit virga from patchy ice clouds. Could be termed Cirrus spissatus or Altostratus, if you care. — 5:21 PM. Your sunset. Nice underlit virga (light snow fallout, likely single ice crystals, not flakes) from patchy ice clouds. Could be termed Cirrus spissatus or Altostratus, if you care. What kind of crystals, you ask or didn’t? Bullet rosettes.

The clouds and weather just ahead

Expect more Altocumulus, Cirrus, and Altostratus today, patchy and gorgeous. Would expect some nice Ac castellanus (one with spires) as an upper level low off Baja starts to move toward us. Some measurable rain likely tomorrow in the area, but probably barely measurable, maybe a tenth at most since it will fall from middle clouds with a lot of dry air underneath them. (Enviro Can mod still sees rain around here tomorrow.)

Middle clouds might get large enough to call the (small) Cumulonimbus clouds, with a slight chance of lightning tomorrow, Thursday, as this low moves up and over us.

So both today and tomorrow will have some great clouds!

WAY ahead; watch out!

After a quiescent period of gorgeous, misleading days, where the temperatures gradually recover to normal values and you’re gloating over the nice weather you’re experiencing by coming to Arizona from Michigan, blammo, the whole thing caves in with strong storms and very cold air heading this way. Yesterday’s 18 Z WRF-GOOFUS model run for 500 millibars (rendered by IPS MeteoStar), was, if you like HEAVY precipitation throughout Arizona, well, truly”orgasmic.” You just cannot have a better map at 500 mb for Arizona than this one from that run. That low center over California, should this verify, would be filled with extremely cold air from the ground on up, cold enough that snow in Catalina would be expected as it goes by. So, there’s even a prospect of a white Christmas holiday season. Imagine.

Valid 264 h from 11 AM AST yesterday morning, or for 11 AM AST, Saturday, beginning of football bowl season I think, which last until February I think. — Valid 264 h from 11 AM AST yesterday morning, or for 11 AM AST, Saturday, beginning of football bowl season, which last until February I think.

Now will this verify exactly like this? Nope, not a chance. But, spaghetti tells us we’re going to be in the Trough Bowl, filled with cold air and passing storms beginning in 8-10 days from now. How much precip and how cold exactly it gets is unknown because these progs will flop around in positioning the troughs that head our way. There will be major troughs passing through, so while the amount of precip is questionable, the cold air intrusion is not. It was just so neat, exciting, mind-blowing to see that such a gargantuan storm has been put on the table for us in that 18 Z run.

Most likely subsequent model runs will take this exact map away, but then put something like it back, until we get much closer to verification day, the 21st. May even shift around on which day is the doozy, too, by a couple of days either side. Still, a really exciting period of weather is ahead.

This may seem odd, but one of the keys to our storms way ahead is the eruption of a huge storm in the western Pacific (and that storm is shown developing in the last day (144 h panel) of the Enviro Can mod.

———–dense reading below————-

That erupting, giant low pressure center will shoot gigantic amounts of warm air from the tropical ocean far to the north ahead of it in the central Pacific. That warm air shooting north, in turn, causes a bugle to the north in the jet stream, a ridge, which deflects the jet toward the north toward the Arctic. As the jet stream does that, there is almost an immediate response downstream from the ridge; the jet stream begins to turn to the south, developing a bigger an bigger bulge, or trough to the south. So, a jet stream running on a straight west to east path across the Pacific can be totally discombobulated when a giant storm at the surface arises and shoots heat in the form of clouds and warm air northward¹. In this case, all of this takes place beginning in the Pacific in about 6 days, so that a sudden southward bulge, a buckling of the jet stream, due to that giant low in the western Pacific 8, 000 miles away, happens over the western US. And voila, our big cold and maybe our big storms, too. then.

————end of lead-filled text———

The End.

————————————-

¹First noted by much-honored meteorologist, Jerome Namias, who did not have the Ph. D. but was great anyway, in the early 1950s.

Altocumulus clouds, Cirrostratus, Cirrus clouds, Definitions

Water vapor molecules set to increase; mid-August chance of rain, too

August 14, 2013 Art Rangno

I wasn’t going to blog today, but rather than disappoint my reader, and seeing a ooupla photos that were kind of nice, I pushed through the laziness. I hope you’re happy now….

Also, humid air is pushing up from the S today, and while it hasn’t gotten here yet (dewpoint here in Sutherland Heights next to my gravel driveway being but 36 F now, its in the 60s at Yuma, Nogales and Douglas. With that invasion of water vapor molecules comes a slightly better chance of a shower, or at least SEEING one somewhere! You might hang out some wash today to further increase the moisture content of the air; it would be a more basic form of “cloud seeding”, maybe “cloud doping.”

Sunset to sunrise, because they imported that way:

SONY DSC — 7:19 PM. Cirrus spissatus, in the distance; foreground and center, Cirrus uncinus, if you care.

Factoid: The amount of rain that continues to fall in the formerly severe drought areas of Kansas and Oklahoma continues to astound. Here, from WSI Intellicast, their 7-days of radar-derived totals. Also note the substantial rains in eastern Colorado and New Mexico. Good news for all.

Radar-derived rainfall totals for the 7 days ending August 13th. Areas of dark green to yellow indicate totals of between four and TWELVE inches.

(colon deliberately left above at left to provide some tension, some anticipation in case you’re bored already)

5:55 AM. Flakes of a droplet cloud, Altocumulus, rather suddenly appeared or moved in.

Altocumulus clouds, Cirrostratus, Cirrus clouds, Definitions, Snow, The weather WAY ahead (10 days or more)

FROPA! (plus some corrections in red….)

January 11, 2013 Art Rangno

2:26 AM, Catalina: S- (light snow), 33.9 F, 0.01 inches so far. Precip not registering on Wunderground map site for some reason.

3:20 AM: S– (very light snow), 34.8 F. Temperature beginning to recover following precip, snow almost over, just a “skiff”, 0.3 inches.

6:20 AM: Total now a measly 0.02 inches, less than expected, but in keeping with jet “rule of thumb”; nil precip until 500 mb core goes by¹, and its just getting here now–120 mph wind now at just around 18,000 feet over TUS, an extremely exceptional event for winds that strong to be that low!

Correction on storm total: Mr. Cloud Maven person forgot that when it snows, the small orifice into which the rain water usually flows without hesitation is clogged by that SNOW and the tipping bucket does NOT tip until the snow melts. It began melting in mid-morning, and by the time it was done melting, there was a total of 0.10 inches, 0.14 inches at the Sutherland Heights gage. This is a lot better than 0.02 inches.

County ALERT gage totals disappointing, too, just a few hundredths to a tenth of an inch; most with zeroes. Mountains reports missing since it fell as snow. (As with my own gage, the snow is melting into the buckets in the ALERT gages and they are now showing precip! )

(Here, the snow has melted and dribbled into the gage–NO it hadn’t!!!!) ((Shoulda looked inside the funnel before writing that!))

Only expecting small Cumulus today, but its cold enough that they could have some ice in them. It would be something for you to watch for.

Here’s the temperature and pressure traces for this dramatic cold front passage (FROPA) here in Catalina last night around midnight with the chart below beginning around 7 PM, this from a pitiful jpeg of computer monitor since the software I use will not print two parameters on the same graph (please fix this, Lightsoft Weather Centre, UK!):

You can’t read it, but the temperature dropped from 50.x F to 33.x F in about an hour, with period of very light snow, no accumulation at the end of that hour. And you can see what we meteorologists call a “pressure check” when a cold front goes by; starts rising immediately.

Yesterday’s clouds

Lots of lenticular formations around, beginning with this rosy specimen just downstream of the Catalinas at dawn:

7:17 AM. Altocumulus lenticularis downstream of the Catalinas.

Lenticular clouds downwind of the Catalinas persisted for hours yesterday. Its sometimes hard to tell that they are not over the mountains, but you can see that in the U of AZ time lapse for yesterday.

BTW, if you want to know how the UFO thing got started, legend has it that it was due to a hovering Altocumulus lenticularis cloud downstream of Mt. Rainier in the 1940s.

Viewing this U of AZ time lapse movie will tell you why lenticulars have sometimes been reported as UFOs. It really does look like a hovering “vehicle” in the morning hours in the movie, and a “hovering”, which is what we know alien spacecraft do; hover. In the face of the strong winds up there yesterday, hovering is, for most folks, unexpected, suspicious behavior. Check it out.

Finally, after the heavy mid-level overcast in the mid-late afternoon, a brief sunset bloom due to a distant clear slot beyond the horizon (way down at the bottom).

12:28 PM. Here's comin' at you; Cirrostratus way up top, below, Altocumulus lenticulars, and Cirrus spissatus (thick ice clouds) — 12:28 PM. Here’s comin’ at you, looking to the west; Cirrostratus way up top, below, Altocumulus lenticulars, and Cirrus spissatus (thick ice clouds possibly evolved from glaciating lenticular patches. Very complex scene. Thought about omitting it because what I couldn’t name and explain things?)

1:02 PM. Altocumulus opacus invaded sky rapidly from the west. Bottom looks pretty much like a lenticular, but it was scooting along, something true lenticular clouds don't do. Hmmmm. Maybe I should omit this one, too. — 1:02 PM. Altocumulus opacus invaded sky rapidly from the west. Bottom part looks pretty much like a lenticular, but it was scooting along, something true lenticular clouds don’t do. Hmmmm. Maybe I should omit this one, too.

1:27 PM. ACSL is back again downwind of the Catalinas! (Altocumulus Standing Lenticular)

5:46 PM. A heavy layering of Altocumulus (opacus) is under lit by the sun for just a few moments. Like me, you may have initially given up on a "bloom", by, by golly, it happened! BTW, as often happens, these heavy looking clouds were a lot higher than you might think, about 17,000 feet above Catalina (from the TUS sounding.) — 5:46 PM. A heavy layering of Altocumulus (opacus) is under lit by the sun for just a few moments. Like me, you may have initially given up on a “bloom”, but, by golly, it happened! BTW, as often happens, these heavy looking clouds were a lot higher than you might think, about 17,000 feet above Catalina (from the TUS sounding.)

What’s out there beyond the present cold spell and the warming after that?

This is kind of intriguing to me even though its kind of a waste of time, too. We’ll be reel cold for awhile, then it will suddenly warm up to seasonal temperatures for a few days. We know that. But then what?

Our models have been churning out wildly different forecasts toward the end of the month, and with those, wildly differing weather occurs here, naturally. These model forecasts are like a 5-foot wide puddle of water on a pot-holed street like the ones we have here in Catalina that they only repair in the most rudimentary way, throw some asphalt crumble in the hole, that its pretty much what they call a “repair.” Maybe its because we’re considered “po’ folk.” Let’s see, where was I? Oh, yeah, that puddle could be an inch deep or three feet deep. You just don’t know for sure.

One way to “dip stick” that “puddle” is in our NOAA spaghetti plots. At the end of this is the latest one from last night’s global data. You can see how wild (humorous) the forecasts are in the yellow and gray lines, indicating exactly opposite conditions in the West at the end of the month for those model runs at 00 Z (5 PM AST) and 12 Z (5 AM AST yesterday). Pretty bad.

The spag plot below from last night’s data suggest the warm ridge has the edge at this point (note clustering of blues lines to the northern US; red lines still confused). With a ridge holding forth, it would be a comfy time in AZ late in the month, not cold and blustery.

Still, its not the final word, remembering that the atmosphere remembers. It will be interesting if it remembers enough to bust our venerable spag plots. That’s what makes it so darn interesting!

The End.

——————

¹Its interesting that such an old style methodology, of the type used by forecasters before the rise of weather computing models, would seem to have equaled our best models in 2012.

Altostratus clouds, Cirrocumulus clouds, Cirrostratus, Definitions, Science stories, Sunsets

Miriam’s sunset

September 28, 2012 Art Rangno

At least former hurricane Miriam gave us a nice sunset of mostly layer ice clouds (Cirrostratus; Altostratus (where thicker). Note portion of halo, upper center, above pointy-top cedar tree on the horizon. Looks a broken streak of droplet clouds (Cirrocumulus) just below that bit of halo.

Today’s overcast of Altocumulus and Stratocumulus, also associated with Miriam, develops some light rain to the south of us now. Wasn’t supposed to get here (from U of AZ model yesterday), but, there it is, SLOWLY heading this way. Will it make it? Don’t think so. If it does, it won’t be much, a trace? Dang.

Next rain here, sometime in October…. None now shown for the next 15 days. Maybe summer stats later today or tomorrow. (Correction, updated at 1:05 PM local based on the US WRF-GFS model run at 5 AM:

the almost “usual” rain has shown up, 324 h from now, that is, Thursday afternoon, October 11th. Below is the precip for the 12 h ending at 5 PM that day. Also, as “usual”, don’t count on it, but its not impossible either. There a tiny heavier rain blob over Catalina or so.

Didn’t get to a rain stat presentation yet due to being absorbed by former company team’s activities in SEA last evening where, at the conclusion of the match, there was a display of sport’s anarchy. The attendees of this event, in some kind of euphoric riot, lost control of themselves, climbed out of their seats and advanced onto the floor of the stadium where only the athletes and their entourages are supposed to be.

Two curious friends were at that game, my friend Nate, who got a big check (250 K$!) from Al Gore at the Whitehouse a few years ago due to being a science star, and my other friend Keith, who made a LOT of money photographing the explosion of Mt. St. Helen’s in 1980 because he was where he shouldn’t have been went it went off. Keith then quit the Ph. D. program in the geophysics grad school at the U of WA and started a company, Remote Measurements, due to all the money he made from that poster of the explosion.

Nate and Keith now share season tickets now to the Husky football games, as Nate and I once did, which I think proves something about fans of college fubball.

What does it prove?

Maybe its that you can like college fubball and still get a big check from Al Gore (who later went on from being Vice-president to a star in the movies).

Or, it just proves that you don’t have to be THAT bright to be a success in science (hahahahah-its just long, hard hours, not brillance, that counts).

And, it may prove that college fubball fans are sometimes not be who we think they are. Feeling defensive here about being so absorbed last evening, so let us not forget that the writer was thanked by the People of Earth with a small monetary prize, a “scroll”, AND…a trophy (!) for his and Peter Hobbs’ body of work in the domain of weather modification, all these goodies being presented in Capetown, SA, in 2006. So, there, IQ feels better now.

As a joke on that that latter thought, my friend and grad school officemate, Ricky, from Harvard U. no less, and I used to throw a football around at lunchtime on the lawn in front of the 7-story department of Atmos. Sci. Building at the U of WA. Before we went out the door to play catch, I warned Ricky that his perceived IQ would drop by 30 points when people look down and see him tossing a football, and, forget dating any of the women in the Department… :} Just kidding!

The End.

Aerosols, Altocumulus clouds, Catalina climate data, Cirrocumulus clouds, Cirrostratus, Cirrus clouds, Wildflowers

Cirrus altocumulus castellano-floccogenitus

March 30, 2012 Art Rangno

We had a rare form of Cirrus yesterday, whose name I have made up in the title as a hint of where they came from, due to the very high altitude and low temperatures of some Altocumulus yesterday. Those Ac morphed to Cirrus, hence the strange, unpronounceable title.

Reminder, weatherscience mavens, its more proper to say “low” temperatures; not “COLD” temperatures, FYI, though you constantly hear it. (“Things”, like coffee, air, chairs in the sun, etc., are hot, warm, cool, tepid, and cold; temperature is not a physical thing, and is high. moderate, or low, etc.))

Still bristling over some unexpected clouds yesterday, so I wanted to complain about something minor, bring some discipline to the field.

Mr. Cloud-maven person was not paying attention, asleep at the wheel, etc., when some Altocumulus castellanus and Cirrus castellanus came a truckin’ over the horizon and floated over Catalina after dawn yesterday, but had not been mentioned in this blog in advance. I am sure, since they had not mentioned from this keyboard, you may have been in some distress yesterday when they showed up and you weren’t sure what was happening. My apologies. It will almost never happen again.

Here are some photos of the interesting clouds that passed overhead yesterday. I was quite excited to see them partly because I had not prepared myself mentally for them. Now, there is something strange in the first caption. But I wrote it that way on purpose because I REALLY want to know if YOU know WHERE the HELL you are, and where the mountains are around here. Next, after that outrage, some interesting banded Cirrus. Then a hint at where those Cirrus came from in the background of the 3rd shot.

DSCN1187 — This banded Cirrus gave some hint as to its origin. Might be termed, Cirrus uncinus, or floccus, or fibratus, its a pretty complicated set.

Caption function not working now for this third shot in WP, so here it is:

3) A nice example of Cirrus uncinus in the foreground, tufted or hooked ice clouds trailing tiny ice crystals. In the background, a clue to the origin of the patchy, banded Cirrus.

4) Another shot of the approaching Altocumulus castellanus (Ac cas) and (Ac floc) floccus clouds as they arrived overhead, some of which have morphed completely into ice (Cirrus) clouds, such as that larger element over the house in the foreground! In the upper left quadrant of this shot are Ac clouds that, to this eyeball, are still liquid.

Droplet clouds have more sharply defined edges because droplet clouds have MUCH higher concentrations of particles in them than ice crystal clouds (which tend to make them “fuzzy”, ghost-like, striated, fibrous, etc.

Why this visual difference, which I want you to learn, to see for yourself and impress your friends?

There are more cloud droplet condensation nuclei than there are ice crystal nuclei. For example, liquid Altocumulus clouds might have 100,000 to 500,ooo drops per liter in them, while ice crystal clouds may have only tens to a few thousand per liter (and then only in newly formed elements) of ice crystals. In general, there are more cloud condensation nuclei than ice nuclei, too.

Today

While “Joe” is spinning up into his little hurricane-like self in some kind of weather tantrum off the California coast today before heading to Oregon, our skies over Catalina will be marked by various forms of Cirrus clouds, ice clouds well above 25,000 feet above the ground, and not much else. BTW, you can follow Joe’s progress here from the U of WA, if interested.

If you’re interested, instead, of following our Cirrus clouds as they approach and go overhead today, go here, also from the U of WA. You see the Cirrus clouds pealing off the main frontal band in the Pac NW and then fading as they head this way. (I would increase the speed of the loop for maxium excitement.)

The End.

Cirrostratus, Cirrus clouds, Definitions, Lenticular clouds

Cloudy with snow above 15,000 feet

March 25, 2012 Art Rangno

On deck, this cloud stream for today, as presented by the University of Washington Huskies Weather Department. As you will see, the whole stream rotating around that low off southern California has been thickening up overnight, a process that will continue, and so it looks like it will be a frequently gray day with Altocumulus, Altostratus, and Cirrus of various types piled on top of each at times. Don’t look for much direct sunlight today. Virga (snow), too, but no rain beyond the slight chance of a sprinkle. Most of the clouds you see will be composed of ice crystals and snowflakes. Also, with the wind picking up aloft today, lenticular clouds are likely again. Look to the NE of Mt. Lem.

Don’t miss a nice sunrise shot this morning.

Yesterday’s clouds

Below, after you have read all the captions, yesterday afternoon’s sounding from our friends in cowboy-on-a-bucking-horse-license-plate-land which, BTW, I think is a pretty cool looking license plate since I’ve been bucked off horses myself a few times and when I see that license plate can say, quite haughtily, “been there; done that”, and tip my hat to the driver. In fact, the horse I was bucked off most recently kicked about as big as the one rendered on that WY license plate, and while I ended up in the hospital with a big bill, HELL it was worth it when you can say things like this and show that you are truly embedded in western culture, which I love after leaving the Temperate Rain Forest-Starbuck’s culture of Seattle:

What do you see in this sounding?

The pinching together of the two heavy lines (temperature to the right, dewpoint to the left) tells you the height of the moist layer in which these clouds formed.

How high was that, you ask, or not?

The “300” line (refers to millibars of pressure) is about 30,000 feet above sea level (27,000 feet above Catalina) and the top of the moist layer, about at the “200” line, is 40,000 feet above sea level, 37,000 feet above Catalina.
So, they were damn high yesterday, running between 27,000 and 37,000 feet above the ground. The bottom temperatures were about -35 C (-31 F), and the top about -63 C. What’s interesting is that lenticular cloud was almost certainly comprised of liquid water drops on its upwind edge before glaciating (turning completely to ice a short distance downstream from that upwind edge.) One of the mysteries of ice formation in clouds is that Cirrus clouds don’t generally form until the conditions for a droplet cloud have been met. This means that when ice is present, it is in a highly supersaturated environment with respect to ice and in spite of the very low temperatures, the crystals can grow and fall out producing trails or fallstreaks as you could see in the Cirrus uncinus clouds.