Last coupla days of March 2016 to feature strong rain threat in Catalina!

Imagine,  rain!  Yep, that’s right.  You heard it first here, right or wrong, as we like to say, over and over again because we can’t think of anything else.

After a couple of minutes of intense scrutiny, cloud maven person has decided to wake up and go blogulent that the computer prog showing a huge upper trough over the SW in 13-15 days, March 29-32nd is accurate.    Will be cold, too.  Little crybaby snow birds might be heading back to Wisconsin or Michigan when this cold spell hits.  Just kidding, flat landers!  (Actually, they’ll be leaving us due to being little crybabies when the temperature hits the 90s-100s every day, temperatures we true Arizonans laugh at.)

Adding to the pile of “credibility” here is that this March came in like a “lamb” I think.  Has to go out as a “lion.”  Or so the saying goes. Science and folk lore, that’s what you get here.

Here’s the actual computer forecast of the trough from last evening’s global data as rendered by IPS MeteoStar:

Valid at 5 PM AST, March 29th. Potent trough takes over the whole of the western US. Note the critical wind jet at this height (500 millibars) is over and south of Tucson, a nearly mandatory requirement for cool season rain here. (Unpublished study, Rangno, 1974; covered the whole US, that study, too.
Valid at 5 PM AST, March 29th. Potent trough takes over the whole of the western US. Note the critical wind jet at this height (500 millibars) is over and south of Tucson, a nearly mandatory requirement for cool season rain here. (Unpublished study, Rangno, 1974; covered the whole US, that study, too.

 

Pretty exciting isn’t it, jet stream way to the south like that?

And this after our too-long-dry-spell pretty much since the first week in January,  the dry spell associated with the strong “El-None-yo”, to be sarcastic after ALL the high expectations for copious rains, the incredible wildflower bloom that would be our pleasure to experience this spring following the pounding rains due to the Big Niño meteorologists and media got so excited about.

DSC_2811
Poppy hills, down Bowman Road here in Catalina. Yes, we have some poppies, but they’re stunted looking, as are the other wildflowers around, struggling to survive in all the dry air since the fall and early winter rains.

But, no.  Moving ahead after draining some emotion…. Thanks for listening.

So’s why CMP going out of what seems to be a long, thin limb here, that other forecasters are afraid of doing, that is forecasting with confidence something so far in advance?

Well, of course its because we got us a pretty darn strong signal again in the NOAA “Lorenz” or spaghetti or “ensemble” plots, where errors1 are deliberately put in the data to see how wildly the outcomes vary.  If the outputs don’t vary a lot, then confidence can be high about a forecast.  “Varying” is seen in how wildly the lines (contours) on these plots are.  Below, an example where there’s not a lot of confidence….

Valid 5 PM, Saturday, March 26th. Really can't have too much confidence here. Arizona is in there somewhere. This came out a few days ago.
Valid 5 PM, Saturday, March 26th. Really can’t have too much confidence here. Arizona is in there somewhere. This came out a few days ago.  Quite a knee-slapper.

(Below we discuss, in contrast, the one from last evening and how we used one of these crazy plots before):

Rememeber, first,  how to spell “remember”,  and then that’s how we knew for sure a big trough would be over us even 10-two weeks ahead back whenever it was when we got a little rain and it was damn cold for a few days this March.

Valid at 5 PM AST March 29th. Relative bunching of red contours of the 500 millibar height contours indicates forecast confidence can be high for a trough in Arizona and the West in the last couple of days of March. So, I'm going for it.
Valid at 5 PM AST March 29th. Relative bunching of red contours of the 500 millibar height contours indicates forecast confidence can be high for a trough in Arizona and the West in the last couple of days of March. So, I’m going for it.

Since this forecast of a good chance of rain late in the month is likely to be quite accurate, there’ll be no need to update you after today.

 

The MAIN thing to remember, in a teaching moment, is to not be afraid when a model run comes out with something vastly different than what I just wrote about 5 minutes after I posted this, to wit, this VASTLY different model output based on data just 6 h after the model outputs above.  I laughed at it, since spaghetti rules, not a single model output.  That’s the teachable moment, I think.

Valid at 11 PM AST March 29th, almost the same time as the model output showing the giant trough in the West. Not here though. From a spaghetti frame of mind, a real laugher, this one. (I think.)
Valid at 11 PM AST March 29th, almost the same time as the model output showing the giant trough in the West. Not here though.
From a spaghetti frame of mind, a real laugher, this one. (I think.)

 

The End
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1 Hahah, as though we don’t make enough of them when we vote and stuff; remember that saying about why there’s an eraser on the top of a pencil?  Very profound.  And, “hey” look at the state of this planet?  We need an awfully big “eraser” these days.

 

 

8 thoughts on “Last coupla days of March 2016 to feature strong rain threat in Catalina!”

    1. That’s pretty funny.

      Notice I didn’t try to forecast how much rain might fall this time due to humbling experience by last forecast when I was bloated with false confidence. Must have been something I ate.
      a

  1. Hi. I stumbled on your website/blog when searching for pictures of contrails. I have become fascinated with contrails that persist and cloud up the sky. I am trying not to think they are “chemtrails” like I have been finding so much of online. So I am looking for real facts and pictures. I thoroughly enjoyed your pictures and comments and even chuckled at some of your writing it’s very entertaining and informative!- Thank you so much – it was a pleasure to read this and I learned a lot too!! great site 🙂

    1. Hi, Maria,
      Well, I might have THREE readers now! Thanks for your comments. I sometimes think I do these blogs only to make myself smile via sophomoric humor, so your comment is especially appreciated.

      Chemtrails. Well, contrails vary due to lots of reasons, size of jet and the amount of water vapor in its exhaust, and the ambient humidity. Because these factors vary so much, so do contrails. Some folks have gone way overboard on what they think is happening up there when contrails are unusual looking to them, and the whole idea of chemtrails is not credible to any real scientists.

      We had an unusual number of contrails overhead of Catalina today. We are not usually under an airway here. It was quite upsetting to see so many wrecking the natural sky.

      And, as you may know, they have some effect on the earth’s radiation budget. When there were no jets flying for a week after 9-11, a peer-reviewed journal study found that the daytime temperatures were a tad higher over the US, while nighttime temperatures were a tad lower. However, at this time contrails are not considered big players in the global climate. Well, went off the rails there a little, didn’t I?

      a

  2. Hi Art: Might as well join “the crowd”. In case you’re still waiting for the rain down there, we’re still getting more than we want. As of this morning. (7am) I have about as much as I had for all of February (7.21 inches) and there’s still a full week to go. That trough over the western US that you’ve been showing- does it mean up here we’ll still be stuck in this wet pattern for early April?

  3. Hi, again, Roland,

    An El Niño expert friend was just pointing out the obvious that I had missed, how this giant El Niño that made such a media impression, and has had us forecasters befuddled about the kind of winter we expected, really has resembled the dreaded “La Niña” mode, where the Pac NW and northern Cal are blasted with excessive rains, and the SW dries up after even good fall and early winter rains.

    A lot of the correlations with El Niños and precip are going to take some big hits thanks to this non-performer.

    Still looking for rain as the month closes out, and then a couple of more shots as April begins, too. We’ll get something, of that I am very sure (51% ). hahahaha

    (Seriously, we will get something here at last in this next series of troughs, ignoring my little joke….)

  4. Art: Starting tomorrow we are forecasted to get a week of straight sunshine! Does that change mean you are finally going to get the rain you’ve been waiting for? Often when we get such a radical shift, someone elsewhere sees an opposite pattern develop. Happy Easter, by the way!

  5. I used to take vacation time off from the U of WA during such periods, they were such a joy. I know everyone in the Pac NW will be joyful. Sometimes a weather break like this makes the front page of the Seattle Times!

    Thanks for the Easter wishes.

    Yep, we have a chance for a sprinkle, eventually out of this situation, and maybe 0.05 inches of dust accumulation today.

    a

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