Definitions – Page 51

Rain 2 for November 2013: 0.23 inches, lightning and a couple of grape-sized hail stones

We have a monthly rain total that’s not zero! But will there be more this month? Stay tuned until November 30th! (Nothing imminent.) In the meantime, a very pretty blue sky day today pocked with residual Cumulus clouds, maybe some virga. There’ll be nice cloud shadows and sun on the Catalinas again today.

In the meantime, here are the Pima Country reports for last evening’s rain. The heaviest amount seems to be at our end of the Catalinas at Pig Spring, with 0.39 inches. Nice.

Yesterday’s clouds and why

Not exactly the way they were supposed to go, the ice cloud shield WAS on the horizon to the NW at mid-day but didn’t advance over us, but rather fizzled out. That’s OK. What was left of it enhanced a spectacular sunset through the rain.

The Cumulus clouds were the stars of yesterday, doing something in the way that the old rock band, Jethro Tull used to do. The members of JT would come out on stage as roadies, fiddle around with equipment for awhile, then suddenly turn around and began playing! Oh, who can forget Jethro Tull and that Aqualung album that roiled the rock waters back in 1971 by interrupting heavy, driving rock with acoustic interludes and flute playing (!!! )? What were they thinking?

Well, our Cumulus clouds pulled a fast one, too, after hanging around, fiddling around not doing much, then blammo, here comes the ice around 4:30 PM, followed by an eruption into an honest-to-goodness Cumulonimbus cloud with a strong rain shaft, sending forks of lightning to the ground, and pea to grape-sized hail bouncing off the roof with winds gusting to over 30 mph. This spectacular happenstance was triggered by a surge of much cooler air in conjunction with the lifting of air associated with our approaching trough just above those Cumulus tops yesterday afternoon. That steepened the lapse rate; spring-loading those Cumulus clouds as it were, allowing tops to rise and still be that bit warmer than the surrounding air and stay buoyant as they rose. Here are a couple of TUS balloon soundings rendered by the Cowboys of the U of WY:

While cloud fattening and ice was expected late in the day with sprinkles and light showers, the U of AZ mod run based on 5 AM AST data was spectacular yesterday morning in foretelling this larger eruption as that cold air moved over us. But were grape-sized hail stones and LIGHTNING expected? Not only “no”, but “HELL no”.

Here’s your day, reprised below, of which the MOST IMPORTANT part was the first detection of ice, very tough yesterday, but a precursor to the rain that began to fall a few minutes later. You can also reprise your day here thanks to the U of A time lapse films. Watch what happens around 5 PM, if you can read the tiny font in the lower left hand corner.

Here is the pictorial of your cloud day below:

3:49 PM. Clouds fattening, no ice visible anywhere yet. Nice cloud street generated upwind of Pusch Ridge, floating over Catalina. Shows wind direction at cloud level is from that direction.

4:01 PM. Nice cloud shadows and sun moving along the Cat Mountains, too. — 4:01 PM. Nice cloud shadows and sun highlights moving along the Cat Mountains, too.

4:34 PM. Something's definitely happening now. Note turret protruding on the left. Clouds evolving into larger masses to the south, the cloud street having broken up. And, these are clouds that — 4:34 PM. Something’s definitely happening now. Note turret protruding on the left. Clouds evolving into larger masses to the south, the cloud street having broken up. And, those massing clouds are upwind of us. Still, no ice evident.

4:35 PM. Ice! I can't believe it. Its going to rain! Can you find it? This is REALLY tough. — 4:35 PM. Ice! I can’t believe it. Its going to rain! Can you find it? This is REALLY tough.

4:37 PM. Close up of ice. A higher top was breaking off to the NE and was converting to ice.

5:07 PM. By this time, ice had formed in cloud clusters all around Catalina, and this beauty erupted upwind.

5:22 PM. About to strike with hail, lightning, wind and rain.

5:35 PM. While the rain and hail weren't done yet, it gave this sunset pictorial. — 5:35 PM. While the rain and hail weren’t done yet, it gave this colorful scene reminiscent of summer sunset color except that the sun would be setting WAY over there on the right out of view.

5:40 PM. Second thunderstorm with hail in formation upwind of Catalina.

The End.

An ordinary beautiful day in Catalina, Arizona

Yesterday was one of those ideal days for us here in Catalina, the kind that draws visitors from all over the country to be together with us. It was also kind of like that space-age, relaxo-elevator music; goes nowhere in particular with a hook or melody, or if there is one, its been eviscerated by sleepy, sedated violin players.

But, going back to yesterday’s weather, you could have taken a nice snooze in the sun yesterday afternoon, with only zephyrs to brush up against you, and with temperatures in the upper 70s, it was perfect for being unconscious for a bit, not having to worry about missing an ice crystal, a patch of virga, or an interesting pattern in middle-level or high clouds that you should write about in your weather diary, or document with a photo.

BTW, tops of the small Cumulus (humilis) were warmer than -10 C (14 F) yesterday, and so not one ice crystal or snowflake fell out of them.

SONY DSC — 6:52 AM. Residual Altocumulus castellanus from the little rainband that went through the night before last.

Today’s clouds (should be interesting)

Should see a band of Cirrus and thicker ice cloud, Altostratus, off to the NW horizon by about mid-day. Some Altocumulus likely around, too. That band (you can see it here, courtesy of the U of AZ Department of Weather). should arrive here here during the mid to late afternoon, producing a fair amount of gray. But also there should be thinner portions before the main icy mass gets here. In those thinner portions and leading CIrrus, there could be some some great patterns, like Cirrus uncinus, hooked Cirrus (“Angel’s hair”). Lower Cumulus clouds are likely to form over the mountains during the mid-late afternoon. Could be really pretty overall if you can get out of your windowless office for a moment to take a peak this afternoon.

Freezing level and the critical -10 Centigrade (14 F) level for ice formation in clouds here in AZ will be lowering especially during the evening and overnight hours, and should lead to ice formation/virga as the clouds fill in later in the day and overnight. This means a chance for measurable rain here. Noticed just now that yesterday morning’s U of AZ mod (available after about 10 AM) did have a few hundredths in Catalina overnight tonight. You can also see this progression of clouds, more or less, in the U of AZ model output from that yesterday morning’s run here¹.

Will write more about later happenings in November when the prior forecasted rain in the models returns; its gone for now!

The End.

———————————–

¹The 11 PM AST model run from the U of AZ is not yet completed, so to HELL with it! Hahaha, just kidding, but must move on to other chores, like digitizing old research flight videos from the University of Washington’s Cloud and Aerosol Research Group I was once a part of but now its over, plane gone, group gone. Life changes, not always for the better, I can see that now. I liked flying in clouds, hearing the graupel hit against the bubble where I had my head, standing on a little stool in the back. BTW, here is what the bubble looks like. I like to look at it even now and remember all the great cloud friends I got to know and write about.

The aircraft dome used by the Univserity of Washington on its research aircraft. RIP. — The aircraft dome that was atop the fuselage of the University of Washington’s research aircraft. RIP. For awhile after retirement, I felt lost as many do. So, I would put this on my head, maybe while doing yard work in Seattle before coming here. It seemed to help the withdrawal I was feeling in those days. Great as a rain hat, too! It really didn’t look that bad.

Rain 1 for November

Here are the surprising totals from the Pima County Alert gauges. Mt. Lemmon received 0.31 inches from last night’s little rain! And most gauges, except the ones in Catalina, got measurable rain. Very nice NWS radar-derived rain graphic here (and below), something that shows we probably got a sprinkle here in Catalina. (Trace detector was not parked outside last night, a huge oversight caused by too much football on TEEVEE.)

Rain totals from 6 PM to just after 4 AM AST last night. Note how rain streamer just missed us to the east.

Some residual clouds are around and likely will provide some nice sunrise shots, but the rain possibility is over for now.

3:49 PM. Altocumulus, getting fatter here, tending toward castellanus and floccus (tiny Cumulus clouds)

5:41. — 5:41 PM. Altocumulus castellanus clouds getting bigger yet, pretending not to be doing anything. No virga showing here, but some was beginning to show up on the extreme SW horizon at dark, as clouds began to fill in toward the S through SW. The appearance of virga would mean that the cloud tops were higher and colder than are seen here.

Next chance for rain is late tomorrow afternoon through overnight tomorrow as clouds fill in late in the day. US mods have backed off rain here, while our Canadian friends with their mod still have some (shown here) as they have calculated a deeper trough; more strength and amplitude (more of an extension to the south of us). However, its a marginal situation and the most that can fall here in Catalina in “Rain 2” would be less than a tenth of an inch.

Way ahead….

Some mod runs still have decent storms affecting Arizona in the 9 to 13 day period, 12th and 17th of November, to be specific, from last evening’s 11 PM run. Not good to be too specific at that forecast range as you know.

The End.

Measurable rain to fall in November (!)

That’s it. Its a kind of news release, best released on the 1st. Its news, of course, you won’t find on other weather sites because maybe they’re chicken, or prudent. Check back on November 30th, and if its rainless again, there will be no mention of this forecast.

But, after the rainless October (we average about an inch here in Catalina), you probably won’t believe me. Check this out from the NOAA spaghetti factory. I got pretty excited when I saw it. I think, you will, too, maybe mention it to your neighbors over coffee this morning, having been pretty convinced yourself after seeing this that storms are a brewin’ for Catalina and vicinity (all of Arizona) in November:

Valid for November 10th at 5 PM AST. Originates with global data obs made at 5 PM AST last evening, and represents a few key 500 millibar height contours after DELIBERATE little errors have been put in and the computer model rerun with them in it.

Thank E. N. Lorenz, a meteorologist for Chaos Theory and maps like the above that show how little tweaks in the original data can change stuff a lot if things are fragile, but not so much if the signal is robust, and things not so fragile. Here a deep trough along and off off the West Coast on November 10th is virtually guaranteed by the blue and red lines that plunge so far to the south off the West Coast. A trough out there, as you know, gives us the best chance for rain as it progresses to the east. The bunching of lines indicates where the forecast, with baby errors, is strongest, like off Asia, and hereabouts, off Baja. Those red lines are pretty much where the south edge of the jet stream will be at this time of year. As you know, we have to be on the north side of the jet during the winter here in old Arizony to get precip, so it looks good for that to happen as we move forward in the month.

BTW, here’s your official forecast for the whole month of November from the Climate Prediction Center (CPC). As you can see, this November is a tough month for them, no real signals showing up for the month as a whole as indicated by the HUGE areas of “EC”, i.e., “equal chances” of above or below normal precip. We’re kind of on the edge of “we don’t know what’s going to happen” (in the popular lexicon, “clueless”) which is good. The signal for continued drought here is not so strong, though it is there. Poor New Mexico, though.

November precip forecast for North America made on Halloween by the CPC.

Cloud photo op coming up

A weak trough ejects from the Pacific and over us beginning tomorrow, and it should bring some great photogenic Cirrus and Altocumulus clouds tomorrow afternoon and evening, likely some “castellanus” if you care. Likely to be some virga (snow falling from the Ac) too, so could be a great sunset shot coming up. With the virga, always a slight chance of a sprinkle-its-not drizzle.

The End.

Pretty cloud day

One of the best, really, never mind all that wind yesterday. No rain, of course, in our future, not even fantasy rain these days.

See usual rehash of yesterday’s clouds, the 60s, in case you forgot, below:

2:09 PM. One of the many examples of iridescence seen yesterday in those Cirrocumulus clouds, or on the very thin upwind edge of Altocumulus lenticularis clouds. Its due to the formation of extremely tiny droplets, a few microns in diameter, that cause the sun's light to go around them and in doing that the white light from the sun gets broken down into its colored components. Do you remember that white light has the wavelengths of all the colors in it? Here you can see some of them. — 2:09 PM. One of the many examples of iridescence seen yesterday in those Cirrocumulus clouds, or on the very thin upwind edge of Altocumulus lenticularis clouds. Its due to the formation of extremely tiny droplets, a few microns in diameter, that cause diffraction in the sun’s rays (see link for a more complete explanation and nice examples). Do you remember that white light has the wavelengths of all the colors in it? Here you can see some of them, and photograph them by performing a replication of the Black Power salute of Tommy Smith and John Carlos from my alma mater, San Jose State, one that beat the Wyoming Cowboys recently in fubball. I added a link in case you forgot and wanted to get worked up again. Yes I was at SJS when that happened down Mexico way, minding my own business doing weather forecasts with a political slant (left, of course, because that’s what made you popular during the rad lib days) for the college paper. Suddenly, I feel like going to San Francisco, putting some flowers in my hair.…

2:19 PM. Cirrocumulus and Ac lenticularis in the same layer. Recall Cc can’t have shading, not that it matters that much.

The End.

Having an effect after all; sunsets, clouds, and the weather ahead

I was driving down in Tucson yesterday, kind of moping around about all the blogs I had done with little or no interest. You may recall from a blog I did a few months ago I reported to my reader that a business site had evaluated the worth of my blog, and due to the amount of traffic it brought, it was found to be worth $25.

But then as I rounded Campbell and headed northbound from Fort Lowell, I saw this sign exhorting fellow Tucsonians to watch clouds! My mood brightened. Maybe there were a few out there that I had affected after all; a whole cloud watching movement had started! I did see, however, that since the sign maker was wondering whether there were clouds in the sky or not, and there was a lot of Cirrus overhead, I saw that I had more work to do.

This sign seen near Campbell and just north of Fort Lowell yesterday afternoon.

Yesterday’s clouds

9:03 AM. Cirrus fibratus in rolls, undulations due to waves in the atmosphere associated with the strong jet stream above us. — 9:03 AM. Cirrus fibratus in rolls, undulations, due to waves in the atmosphere associated with the strong jet stream above us.

In case you were asleep, watching Monday night fubball, and NOT watching clouds, here is yesterday’s magnificent sunset as the sun underlit those dense Altostratus clouds that developed from thinner Cirrus ones during the afternoon and evening.

Today, more mid-level clouds and with strong winds aloft, we should see some lenticular clouds in the lee of the Catalinas. Videoing them would be a good thing for you to do because you would, in fast playback, be able to see how they keep forming on the upwind side and disappearing on the downwind side while holding their overall position. If the moisture increases, they expand, and if it decreases, they shrink and dry up, something likely to happen later in the day.

While that’s going on, there’ll likely be some Cumulus and Stratocumulus off to the north, and since the air is going to be much colder aloft to the north today, some ice is likely to form in them late in the day in those northern clouds, leading to some virga. Those lower clouds, according to our models, should begin appearing around here, too, in the late afternoon and evening. Alas, measurable rain is very unlikely, and with this, last little threat, October 2013 will go out rainless here in Catalinaland.

Farther ahead…..

More middle and high clouds and great sunrises and sunsets are likely on November 3rd and 4th as a little upper level trough creeps in from the lower latitudes of the Pacific off Mexico. It was once projected by the models to bring rain to here, but now it seems only a sprinkle is possible; most of the tropical moisture shunted to the south and over northern Mexico.

In the longer term, while all “fantasy rain” has disappeared for AZ based on last evening’s 11 PM AST model run, stronger than normal storms are showing up for California later in the first week of November, and with that, we’ll always have the hope that this time, the “fantasy” in that model calculations is no rain shown for here.

The End, but enjoy those pretty clouds today!

More fantasy rain eventuates from tropical influences for SE Arizona in latest model run

My fantasy rain team (I call, “WURF-GOOFUS“) already has FIVE inches of fantasy rain in Arizona for November, and here’s more from last night’s 00 Z model run! In case you went to school lately and have trouble finding where you are, I have added an arrow on the map so that you’ll know where SE AZ is (“hey”, we’ve read those stories about HS students not being able to name states….)

Valid for Wednesday, November 6th at 5 PM.

And its not only this map, but a few after this as well. Here’s 24 h later and its STILL raining in SE AZ, with a rain center right on my house!

Valid for Thursday, November 7th at 5 PM AST. How great is this fantasy rain?

I’m thinking now that my fantasy rain team from WURF-GOOFUS has six or seven inches predicted for just November! OF COURSE, its not real rain, its fantasy rain, but, there it is again.

Losing control, the rainless October, the mostly clear skies day after day getting to brain functions, hallucinating again over model outputs of clouds and rain…. Must seek treatment.

The End.

Not likely to verify, but a wonderful map (but, “trending up” in twitter-speak)

This is definitely not the same title as was a few days ago for a similar map, one also valid for Nov 3rd-4th. That title was quite different: “Not likely, but a wonderful map.” The rainy Arizona map back then from our best model showed a tropical storm and moist plume being drawn northward into AZ.

Almost the exact map as that one a few days ago has shown up again out of the blue, if you can say that when you’re talking about clouds and precipitation. There’s been nothing like that former map since that first time it showed up, and, in view of how odd it was, you tend to write it off as something you’ll not see again. But there it was again, now only 10 days out.

Below, the happy, rainy AZ map churned out by last night’s model run based on global data taken around 5 PM AST yesterday ( from IPS MeteoStar):

MOdel outpur valid for 5 PM November 4th. Shows tropical storm remnant being sucked up toward Arizona with lots of rain already here. — Model output valid for 5 PM AST, Monday, November 4th. Shows tropical storm remnant being sucked up toward Arizona with lots of rain already here. Green blobs denote where the model thinks rain has fallen in the prior 12 h, which here is the entire State of AZy!

Below is the pattern aloft that steers (hahaha) all that moisture into our water-challenged State, one that has a lot of steers.

HOWEVER, this rainy situation requires a lucky conjunction of a Pacific trough coming in out of the Pacific onto the southern California coastline, while a tropical storm/former hurricane is off Mazatlån at that same moment. If these two features of interest are just about anywhere else than is shown here in these model projections, forget it.

The flow pattern in the middle of the troposphere, around 15,000 to 20,000 feet above sea level. Yep, that's right, half the air is gone by the time you get to only about 17,500 feet! — The flow pattern in the middle of the troposphere, around 15,000 to 20,000 feet above sea level. Yep, that’s right, half the air is gone by the time you get to only about 17,500 feet!

The first time this rainy map was shown for Nov. 3-4th, back about five days ago, the chances of it actually happening were probably somewhere around 0.2 percent. Just too much had to fall into place. Coming up twice, however, jacks the lucky numbers up to, oh, maybe to an 8 percent chance of actually happening as a wild guess. Not a great chance, but one that’s trending upward. You know, after the rainless October that’s about to finish up, we really deserve this storm in early November. The NOAA spaghetti factory has good support for a trough along the California coast at this time, so its likely THAT ingredient will likely be in place on November 3rd-4th.

Yesterday’s clouds; yes, there were a couple, some patchy Cirrus and a little band of Altocumulus, some of the latter trending toward lenticularis-ee ones. later on. Here they are.

2:37 PM. Patches of Cirrus drift across the southeastern sky.

The End

Expect a cloud sighting today

Probably an Altocumulus or Cirrus.

The End.

In memoriam: Pepper

Not likely but a wonderful map

Last evening’s model¹ run based on global data from 5 PM AST yesterday, gave us this, the remnant of a tropical storm barging into Arizona on November 3rd, just after our rainless October closes out:

Ann 2013101900_CON_GFS_SFC_SLP_THK_PRECIP_WINDS_384 — Valid at 5 PM AST, November 3rd two weeks from today.

As an expert “spaghetti” decipherer, you can easily see from the map below that there’s not much chance of this happening though its not completely impossible. Too much “noise” in the pattern around here (lines aren’t bunched like they are off Japan and in the western Pacific). I just posted the map above because its the first one in SO LONG that had any Arizona rain on it, that green and blue stuff on the map above.

Valid at 5 PM November 2nd, the day before the map above, but close enough.

Who knows, maybe there’ll be a cloud over us one day again, too.

Of note… unusually cold air for October is poised to rush into the eastern and central US in several waves during the next two weeks; those events have a much higher probability of occurring according our venerable NOAA plots of spaghetti like the one above. Likely will see cold air refugees beginning to bail to Arizona in their droves from eastern units of the country as October low temperature records fall.

Its great to be where other people want to be.

The End.

————————

¹Namely, the Global Forecast System-Weather Research and Forecasting (GFS-WRF) model, pretty much our best.