OK to talk about a chance of rain again

With the New Year getting underway and all the excitement about the a possible economic rebound, I felt I couldn’t inform you that the model runs had gutted any chance of that rain here in Catalina in the next two weeks since the last post entitiled, “Return of the cutoffs followed by a Pac blast.”  I know you’re happy, too,  when you hear about a chance of rain in Arizona, and I would have made you feel bad after raising your hopes like that.

At that time, model outputs,  as far as the “Pac blast” went, were fluctuating wildly, but were at least consistent at that time showing a chance of a decent rain this Friday from a cutoff low dribbling down the West Coast.  That low was then supposed to “orbit” off Baja for a day or so, and then drift across southern Arizona and over my house, with rain with it.

Well, it ALL went away in subsequent model runs!

It was awful; I couldn’t bring myself to tell you about these dry forecasts, thus reversing myself and appearing to be wrong at the same time.

Perhaps I was being irresponsible as a weather discusser and I apologize.  No TEEVEE weather presenter would go silent for several days after telling you rainy things were on the horizon and then, with those days getting closer and the prediction changing to dry days ahead, not update you.

So, why didn’t I give you the bad news?

First of all, I didn’t want to hurt your feelings by saying something that wasn’t going to happen anymore, something you read here and counted on.  Perhaps I was being overly considerate.

And, also I remained silent because when the models have a great deal of “eracticity”, (i.e., huge fluctuations) such as they do with cutoffs, and certainly as they were having about where that Pac jet would bash the West Coast (would it be Juneau, AK or San Francisco?),  sometimes its best to “stay the course”  (hmmm, sounds like a political slogan).  Sometimes, when models fluctuate as they were, things resolve themselves in the direction that you are biased in (occurrences of rain), and YOUR OWN PRIOR FORECAST!  So its best to hang on (in silence).   ((That’s really what I was hoping for, to pull out an erroneous writeup at the last minute.))

And today is the day!  I can smile again, self esteem climbing that bit, because I can now present you with some chances of rain again.  I don’t even have to mention those awful dry, contrary model solutions (“solutions”, hah!) that would have made you sad.

Check these out from IPS Meteostar’s rendition of the WRF-GFS model run from just last night for this coming Sunday night, about 11 PM LST.  Note green blob in SE AZ!  (OK, the rain comes on Sunday not Friday as mentioned earlier, a mere forecasting peccadillo):

The “Pac blast ” (where the incoming jet stream impacts the West Coast has shifted southward again in this latest model run as seen below for Sunday afternoon, Jan 23rd,  in those reddish areas that denote the heart of the jet stream, shown over northern California.

As lows and waves accompanying that flow cruise into the Coast, some precip is shown in the northern third of AZ.  I think we can do “better” in the days ahead than just a tiny bit of precip north of Flagstaff a couple of times.  Hope so anyway.

The End.

By Art Rangno

Retiree from a group specializing in airborne measurements of clouds and aerosols at the University of Washington (Cloud and Aerosol Research Group). The projects in which I participated were in many countries; from the Arctic to Brazil, from the Marshall Islands to South Africa.