“Deja vu all over again” coming on Nov 13…

Maybe….  (Keep in mind those models like to tease us that far out, but, plenty of reason to be excited some more again 🙂

But what a great, potent storm that was last night!  Producing O.48 inches here in Catalina at Golder Ranch road above the bridge, it was “all it could be” I’d say.  Another hundredth or two are possible at the very tail of this rainband as very light rain continues to fall.  Estimated wind gusts around here, in those less than one second “puffs” last night  that blasted up against the house and took the power out, 60 mph. The rain should end by 7 AM in Catalina, though.  The Catalina Mountains, though some reports are missing, seem to have gotten an inch or so.  Check here.

But hang on, the models have some very un-Arizona weather ahead.  Sorry snowbirds.  The National Center for Environmental Models (NCEP) continue to show some powerful storms for AZ and Catalina in the days ahead.  So what’s happening?

Persistence.   The jet stream its river-like steering of highs and lows like logs in the water likes to get stuck at times so that the same kinds of storms recur for a period of weeks in a region, something meteorologists have known for decades and we call that tendency “persistence.”   Droughty periods in winter occur  when the jet stream is away from us, or the flow in out of the NW or N even when its close.   Rainy spells here occur when the core of the jet at mid-levels circumscribes Arizona (that is, is located to the S of us),  and the flow is from the southwest, plus or minus some, as it was last night and now.

Last night’s model runs for about mid-way (mid-levels we might also say) in the “troposphere”, the domain where clouds occur, really shows this tendency since almost the EXACT same configuration of the jet stream over us this very minute is shown AGAIN EIGHT days from now, a configuration that would also be associated with a powerful storm then.    How great is that unless you are a snowbird?

These bends in the winds such as we have going by over us now are called “troughs”, air rises, producing clouds and precip occurs mostly on the east side of the bend, and clearing conditions on the west side.

Check these two “twin” maps out from IPS Meteostar:  The first is for right now, 5 AM this morning, and the second map is for 5 pM this November 13th!  And there are gobs of precip from other “troughs” that go by even before this, the next one as you know from the local forecasts, goes over us this Monday.  That trough, too,  also caught in the same overall pattern where the flow comes down the West Coast from the northwest, reaches the “bottom” over Arizona (that is, the jets most southerly latitude in a trough) and then heads off toward the northeast into the Plains States and Upper Midwest.

Weather with this pattern, one that is more typical of spring?

Colder and wetter than normal in the West, warmer than normal back in the East overall for the period that this “persistence” pattern holds up.

Well, lots of reasons for excitement here.  We should really be building snowpacks over the next two weeks or so, maybe put a little dent in our drought.

 

Hope this is partly intelligible.

The End.