On this station plot map for the Tucson area, generated by the University of Arizona’s Hydro and Atmospheric Sciences Department, now has a point for little Catalina/Sutherland Heights! Check it out. Sample map below. Now you can see how our predicted weather varies with those points around us over the next few days. How great is that?Some rain from our incoming cold front is just about here as a line of showers approaches from the west. Hoping now for a tenth of an inch is all.
Had some nice scenes late of little Altocumulus castellanus shedding light snow showers or “virga.”
The weather ahead and way ahead
March. a lamb upon entry, will roar on the way out. While only a little rain will likely fall today, several more troughs are in the works, during the next ten days and they are looking much more potent than today’s trough and front passage, probably bringing cold enough air that some people will start complaining about how cold it is; probably me. Looks, too, like abnormally cool weather will cruise right in to the first week or two of April. Bye-bye heat!
I thought you’d like to read this (Peru’s Niño), forwarded to me by Niño expert, Nate M. Pretty incredible to read about what is happening down there in the wake of the Big Niño of 2015-16, which really turned out to be more of a couch potato in terms of weather production in the Great SW.
But, all this winter, along the Equator near the coast of South America, there has been something we used to call an “El Niño”, but is downplayed or ignored these days because of a new definition that seemed to explain more weather when it occurred, “Region 3.4” a large zone along the Equator WAY out in the Pacific rather than something near the South American coast (that zone now called, “Regions 1 and 2”), as nicely illustrated by NOAA here.
But what has been the effect of what we might call the “Classic Niño”, a warm strip of water along the South American coast, one that doesn’t extend too far into the Pacific? “Read all about it”, as they used to say. Its pretty remarkable.
And here’s what the SST field looks like. Its boiling down there off South America! (Speaking figuratively, of course):
Peru’s Niño can be thought of as a “classic Niño”, the ones written about in the decades before about 1990 or so when the definition of what constituted a NIño (or Niña) was expanded and delineated more sharply among several definitions that were floating around. We ended up focusing on a region WAY out in the Pacific Ocean called, “Region 3.4” that SEEMED to explain more over the prior years.
What’s so interesting about this is that the “Classic Niño” has been underway pretty much all this winter, and we’ve had, especially in California, a classic Niño response; that is, abnormally heavy precip farther down the West Coast that no one anticipated.
Well, the correlations with Cal precip and “classic Niño” occurrences will take a huge jump upward after THIS winter!
End of Statement (hand-waving) on Niñoes.
Local weather statement: for immediate release
Cooler, fluctuating weather foretold here for that latter part of March, I don’t know how many weeks ago, is on the doorstep after the long, anomalously hot dry spell. Poor wildflowers have been suffering, too, fading, looking a little stunted after a great beginning, one rivaling the great displays of 2010.
All of the local weatherfolk are on top of this now, and so no point recasting that stuff. HECK, you can go to Weather Underground1 and get as “good as can be” forecast for Catalina (Sutherland Heights) out to ten days! And, there’s nothing worse for a weather forecaster with forecasting in his blood, than to be excited about an “incoming” and when you mention it to a neighbor he replies, “Yeah, I heard about that already. Supposed to get a quarter of an inch.” There is no air whatsoever in the “balloon” after that. So, if you have a weather-centric friend who says something about the upcoming weather, pretend that you haven’t heard about it yet, “DON’T say something as hurtful, as “Yeah, I heard about that already.”
So, here, we go the long route because most weatherfolk are afraid to go too far into the future because its often WRONG. Our models tend to lie a lot after about even a week, so only the brave go out even ten days!
However, here, we go out as much as two weeks and more because its not a truly professional site but rather want to get something out there earlier than other people, sometimes called a “scoop” in the news and weather business. That’s why our motto here is, “Right or wrong, you heard it here first!” Furthermore, if a longer range forecast posted here is WRONG, you won’t hear about it anymore!
Cloud maven person will say this about the first incoming of several fronts: comes in early Thursday morning, its strong! Rainfall potential: 10% chance of less than 0.12 inches, 10% chance of more than 0.75 inches. Best of those is the average, or about 0.4350 inches in this one. It has great POTENTIAL to be a soaker, but mods have been all over the place; hence, the large range of potential amounts. At least some measurable rain seems to be in the bag, a paper one please, because plastic is insidious. Note, CMP’s forecast is more generous than that found in WU’s latest forecast for Catalinaland.
The weather WAY ahead, unprofessionally so
Let us look beyond the professional forecasting limits to April:
We know we got several storms/fronts zipping across AZ as March goes out like a lion, but what about April?
Looks like that pattern will continue into April with temperatures below normal for the first part. The end of the unprofessional forecasting portion of this blog, though we do have our NOAA spaghetti to hang our umbrella on…. Check it out for about two weeks ahead.
Some clouds recent clouds, including a couple from yesterday
———————– 1Although “Weather Underground” might sound like an org has a radical origin, maybe something left over from the late 1960s, this particular one was NOT formed by 60s “weatherman” terrorists like Bill Ayers and Bernadine Dohrn (the link is for those of you who may have set trash cans on fire, as happened at San Jose State to protest the Vietnam War, to look back at those days in horror or nostalgia; take your pick) , but rather by genuine weather geeks (haha, I count myself among them, those that can’t get enough of weather, there can never be too much, like the guys mentioned in this “Cloud City” article.)
The title represents one of the great forecasting lores of our time, developed over centuries, really, that will once again verify. BTW, this particular lore has a “skill score” up around 0.9011. Its unbelievable, really. If March “roars in like a lion” count on the opposite at the end of the month. Many of you will harken back to March ’83….as an opposite example if what’s a ahead for us this time around.
So, since March 2017 started out tranquil (docile, like a lamb) and a little too warm, “out like a lion” means not just cooler, but even cold, windy, turbulent, unsettled days, rain here and there in Catalina, snow in Catalina Mountains; in other words, a lot of weather fun! And, all this happening a time or three during the last ten days of the March as the month rolls to an end.
Count on it2.
Next report: when rain threatens here in March. Well, maybe sooner.
1Perfect predictability would be 1.00
2The exact days of rain, wind and cold are still pretty uncertain, but they will roar in. You can’t expect “lore” to nail down the days!
Doesn’t look promising for much rain here in Catalina in March, however. No rain in sight through the next 10 days at least.
Let’s check our 7 inches with what’s happening upwind, say, in CALIFORNIA, and see if there’s been any drought relief there, through February, via the CNRFC:
As you are likely to know from many media stories last year, Cal was in a drought siege of five straight years, with but got a little relief last year in the northern part thanks to help from the giant Niño, one of the strongest ever.
Alas, it was one that failed to deliver as the big rain producer for the south half of Cal and the SW in general as was expected.
In case you’ve forgotten how bad things were in Cal, let us look back at what was being said, those horrific appearing drought maps, and also how hopeful were were at the time that the Big Niño would take a bit bite out of drought. This is a really good article:
Then, when the Big Niño faded away like maple syrup on a stack of buckwheat pancakes last spring and summer, we were surely doomed for more dry years. And, for a time, the dreaded cold tongue of water in the eastern equatorial region, the so-called, La Niña, started to develop, which would be no help at all for a good rain season like a Big Niño is, usually.
The Niña faded away, too, to nothing as the winter went on, so we really didn’t have much going on in the tropical Pacific to help us figure out what kind of winter rainfall regime we were going to have om 2016-17. Not having anything going on meant winter rainfall could go either way, a difficult to figure out situation for season forecasters.
In retrospect it is pretty astounding how big a signal must have been out there SOMEWHERE that this winter was going to be one for the history books on the West Coast in general, and in particular, for Californians. Californians saw their drought chewed up and spit out in a single winter, including snow packs so high the height of some mountain peaks have been revised. (I’m kidding.)
No one saw such an astounding winter coming.
This winter sure makes one think of the QBO (Quasi-biennenial Oscillation, one up there in the Stratosphere where there’s almost no air (haha, well, practically none)… Did the QBO have a role in this astounding winter; was there a delay in the effects of the Big Niño even without a bunch of convection in the eastern Pac tropics? Doesn’t seem that could be right…
But, William “Bill” Lau, U of Maryland scientist, reported some statistical evidence of such a lag way back in ’88 due to a QBO connection of some kind and ENSO, no physical cause could be discerned, however, not yet, anyway. Lau, 1988, is reprised below for readers who want to go deep:
Light rain showers overnight, just before midnight, and again just after 1 AM AST, raised our Sutherland Heights storm total to 0.33 inches, decent but disappointing in view of model and personal expectations (0.60 inches).
What was especially interesting is that those nighttime light showers didn’t show up on the TUS radar, suggesting very shallow tops, perhaps a “warm rain” event, one not having ice, or an “ice multiplication” event with tops warmer than -10° C, about where the tops were on the 5 PM AST TUS sounding.
By this morning, the tops were barely below freezing (about -3° C). Don’t expect to see ice today, except at Cirrus levels!
Last of the Cal rain blasters is making its way across the State today, with another 5-10 inches expected in favored Sierra and coastal ranges in the next 24-36 h. Numerous sites north of SFO have now logged over 100 inches since October 1st! Imagine. Great to see that Cal drought vanquished in a single year, so unexpected. Let’s hope the Oroville Dam, N of Sacto, holds.
PS: Using point and shoot cam now with “real” camera in the shop for awhile.
That’s why you come here, to answer important questions like that. After all, those precipitating clouds could have been Nimbostratus, Stratocumulus opacus praecipitatio, Cumulonimbus capillatus incus flammagenitus, or even just “plain” Cumulonimbus capillatus (no anvil), and possibly, Stratus opacus nebulosos praecipitatio.
Of course, with no large fires around, we can at once rule out Cumulonimbus capillatus incus flammagenitus….(the new name for clouds on top of fires, formerly referred to by the more accessible terms, “pyrocumulus” or “pyrocumulonimbus.”
For the curious, and since I broke my camera and don’t have the dozens upon dozens of photos to regale or bore you with, I will reach into the archives for a shot of “flammagenitus” and show you one from the pyromaniacs’ paradise, Brazil!:
Now, on to more recently viewed clouds, like yesterday’s:
Later these scenes were overtaken by a slab of Nimbostratus and steady light rain for a few hours.
A note on the recent southern Cal rain blast
As you know, up ten inches fell in some mountain locations in southern California as a monster low pressure system smashed into the coast near San Francisco1. You might recall, too, that the shift of the jet stream (and thus storm track) into the southern portions of California was well predicted two weeks in advance in those crazy spaghetti plots. You can’t always get much out of those plots except maybe the degree of uncertainty in weather patterns a couple of weeks out, but that was a rare case in which the signal far upstream for something strong barging into southern Cal also strong. And, of course, we are experiencing the residual of that storm, also as was indicated in those plots (“…the weather change around the 18th.”
Presently, a another sequence of extremely heavy rain is in the pipeline for central and northern California starting today, which will take a few days for it to come to an end.
Following a break, what was intriguing in the model outputs, and a little scary was that it appeared that yet another scoop of tropical air was going to jet across the Pacific under another blocking high in the Arctic and Gulf of Alaska into California. Take a look at this prog:
Here’s where spaghetti can shed some real light:
So while it is still possible that some model runs will indicate a blast from the sub-tropics affecting Cal, they can be pretty much waived off as outliers (not impossible “solutions” but rather unlikely ones. Breath easier Califs! At least after the current onslaught ends.
BTW, can you see what kind of weather is indicated in this plot for the SW and old Arizony?
Cold; temperatures below normal, precip likely at times.
——————————– 1The low pressure center that passed over San Francisco yesterday was not as deep (988 millibars) as the notorious “Frankenstormmaggedon” of 2010 which barged into Frisco with a 979 millibar center. You may recall, too, that spaghetti had strongly suggested a “Frankenstormaggedon”, as it was later called, also more than ten days in advance. Recall, too, if you can recall, that 2009-10 was an El Niño winter with this kind of thing pretty much anticipated.
For history buffs, I reprise that January 2010 storm as seen on our national weather map. You may recall that, if there’s anything left in that noggin up there, that Catalina experience no less than THREE inches of rain as this system went by, taking a couple of days:
Well, it will be pretty obvious, ludicrously so to spaghetti lovers, the sequence shown below. It goes from “warm in the West (again); cold in the East pattern to another undercutting flow from the Pacific, the kind we’re having right now under the “soft underbelly” of a big blocking high, except that the tropical flow from the Pac this time is a little too far to the north to give us anything.
But, it will be another floody situation for northern Cal in the coming days. Some places, mainly north of “Frisco”, have already picked up 4-6 inches in the first blast which hit yesterday. Ten to 20 inches more is likely over the next week at favored locations. Having quite the water year there, really a lot of water year.
You may recall that the current situation, alluded to in the “break on through to the other side” refrain used here about ten times, was well predicted about two weeks in advance! That’s what spaghetti can do for you!
OK, enough jabbering, let us move on to the current exciting examples that popped out from last night’s global data ( there are outputs after adding little errors at the start of the model run, to see how the flow is changed with them in it. Sounds crazy, I suppose, but is considered a huge advance in forecasting, a stupendous tool, that is, to make errors in models at the beginning of the run). Heck, they even do that in climate models that simulate 30-50 years from now, and you’d be amazed at how the tiniest fraction of a degree change the beginning makes (see Deser et al 2012).
Well, the first one’s not so exciting since we’re dry and hot for this time of the year, and its a common one that can get stuck for weeks at a time, so you REALLY hate to see models project a bulging ridge poking north along the West Coast. It could mean a rainless February here, if it persisted.
Here’s the exciting follow up, though, pretty unexpected given the above, showing a sudden collapse of the West Coast ridge regime, and strongly suggesting that wet spell has begun in Arizona, including regions of Catalina and Saddlebrooke:
So, you’ll want to get outdoor work done before this.
Historical note of interest, added value content, etc.
Some of you may remember that the 564 decameter contour (those red lines) at this level (500 millibars or around 18,000 feet above sea level on average) was used in the early years of forecasting before computer models (50s and early 60s) by southern California forecasters to demarcate where rain would fall in California–at and north of where that 564 decameter contour intersected the coast when upper troughs came in. The Old Forecaster remembers, though not much else…
So those red lines barging into southern Cal after a LONG fetch from the subtropical Pacific in the plot above mean central and southern Califs better watch out for some major rains a little before we ourselves get a dousing around the 18th of Feb.
Isn’t it great what spaghetti can do, that is, constrain our future weather to fairly certain outcomes two weeks in advance!
There was a sunset yesterday, btw:
Upper level snow flurry passes south of Tucson! Trying to generate some excitement here….
Since we have nothing better to do for quite a dry while here in AZ, and CMP is from southern Cal, where he kept a weather and a cloud diary1 and played baseball2, here’s the latest on the Cal drought we’ve heard so much about, below, from the Drought Monitor folks at the University of Lincoln Cornhuskies University as of January 24th.
Added to this map is a couple of rainfall totals in the drought affected regions from January 1st through the 23rd, 2017 (i.e., only partial monthly totals) from the CNRFC, a superb site, btw:
Well, as you can see, it takes India monsoon caliber rains3 to end drought completely in California. Or, maybe the DM folks are just a little behind; could be. Avalanche hazards have been moderate to “extreme” during this period due to the tens of feet of snow that have fallen in the Sierras. Yay for California water supplies THIS water year!
Here is a table of the top 20 rain totals through January 23rd from the CNRFC:
————————————– 1Perhaps you don’t believe me that I kept a weather and cloud diary growing up. Here a report from the San Fernando Valley:
3Rainfall totals can be over 100 inches a month at the monsoon’s peak in India. The record is 366 inches in ONE MONTH at Cherrapunji in the NE corner of India in the Assam region. Of course, CMP must go there; its on the “bucket list.”