Timing of rain–go here

Hi, again,

Go here for as good as the timing on the incoming rain gets, graciously provided by the University of Arizona Department of Atmospheric Meteorology.  This model run, now in progress says that rain begins to move into the Cat Mountains by 3 PM tomorrow.  Exciting.   Also you will notice in this “total accumulation of precip” presentation, that we’re expected to get a very nice rain, looks like half inch to an inch by Friday, 2 PM, and even then it ain’t over.   Also you’ll see that by that time, areas to the north of us get SEVERAL INCHES according to this model.   However, those indicated amounts have to be used with caution since they originate with imperfectly known cloud and precip processes that we try our best to represent in models, but still come up short most of the time.  In this case, there is a “tendency” in this model to over-predict the precip.   And the onset timing could be off some as well.

Also, if you like to see time lapse of the clouds you might have missed yesterday, they have this U of A campus site with the roof cam pointed at the appropriately named Cat Mountains.  Us in Catalinaland are just behind Table Mountain, Pusch Ridge in that time lapse.  This time lapse will REALLY be interesting in the next few days.

You will also see, if you look closely, why we think of Cirrus clouds as “precipitating” clouds.  In the time lapse you will see trails of ice crystals falling out.  They are virtually dust like in size (well, they run 100-300 microns in diameter, those ones falling out), but if in it, you would hardly notice that kind of precip.   You would only see glints of crystals going by, and a dust like coating on the ground (if you were on Mt. Everest or K2).  So, once out of the body of the cloud they start to evaporate, fall even less slowly, and the trail becomes almost horizontal.   Sometime horizontal (flat) layers have precipitating Cirrus above them constantly dropping new crystals into the flat, constantly thinning layer in kind of a quasi-equilibrium.

Oops, enough of that.  Here’s is yesterday’s Cirrus-induced sunset, definitely more interesting than the above.


The End and waiting for the RAIN!