A look at Catalina’s empty water year container so far; but spiget may be about to be turned on

While waiting for measurable rain to begin piling up in November, let’s look at no rain so far for the current water year which began October 1st:

Updated to 2013 Catalina WY rainfall averages
The observed monthly rainfall is shown by an adjacent column in yellow on the right… (hahaha, trick or treat, there isn’t any yet)













In fact, speaking of piling up, here’s some rain in this forecast from the Canadian GEM model already for the night of November 4th-5th, and, of course, windy on the 4th before the cold front with this barges in.  And, I am happy to report that the USA WRF-GFS model is ALSO showing rain during this time, after being rather reluctant until the run from last night at 11 PM AST, seen here.  This is lookin’ good now for our first measurable rain in over a month.

Valid at 5 AM AST November 5th.  Colored regions in the lower RIGHT panel are those in which the model thinks it has rained during the prior 12 h (overnight, Nov-4-5).
Valid at 5 AM AST November 5th. Colored regions in the lower RIGHT panel are those in which the model thinks it has rained during the prior 12 h (overnight, Nov-4-5). You might have to use binoculars to see it.

But wait, there’s more!

Amajor precip episode has shown up in the 11 PM AST WRF-GRS run from last evening! Check out these renderings from that model run from a site I like, IPS MeteoStar:


Valid for Thursday, November 14th at 11 PM AST. Colored regions indicate where rain should have fallen in the prior 12 h. Note heavier blob over us, indicated by darker green!

Valid for 11 AM November 15th. Precip for the prior 12 h ending at this time shown by colored regions. Note bull’s eye in this area (likely associated with mountains around here). So, the mod thinks it could be raining over a 12-24 h period.




























In the past we have seen numerous examples of “fantasy rain” produced for us here, often involving decaying tropical storms, that turned out to be completely bogus in this time range, that beyond 8-9 days.  Its pretty normal for goofy things to show up in these models beyond that time.  Just too much chaos going on and using measurements with their inevitable errors, even if fairly slight ones, not to mention that we don’t really have all the answers to how the atmosphere works.

So, what do we do?  We deliberately input errors into a few model runs at the very beginning and see what happens, how crazy the key contours and isobars get.  “Pretty cool, huh?”, as Bill Nye the science guy might say if he were writing this.  Where they remain pretty steady, that’s where a prediction, even one ten or more days out, is going to be very reliable.   Here’s is a sample of one of those crazy results from NOAA:

Valid at 5 PM November 10th
Valid at 5 PM November 10th
























The plot above indicates that there is a very strong signal for a big trough and storms along the West Coast 10 days out.  The red lines show that there is a strong signal for the jet stream from the subtropics to be a bit south of us.

The main point here is to point out that while the DAY OF THE RAIN on those forecast maps might change in the models, there are still going to be a number of days where troughs and fronts threaten to bring rain yo Catalina over the next two weeks, and one’s likely to make it as a rainy one.

Thinking now, having a rain bias (“truth-in-packaging” note here), that November’s rain will be near or above normal.

Today’s clouds

Look for a few Cirrus and maybe Altocumulus to appear late in the day with the likelihood of a nice sunset shot.