Trough Bowl to occur in West

Being the time of football bowl games, and with 35 just ahead, it seemed an appropriate thing to say.  And, let’s face it, there are never enough bowl games1.

You can see this “trough bowl” phenomenon in a 5-day average of the contour heights at 500 millibars (around 18,000 feet), courtesy of the Washington Huskies Weather Department, whose company team is actually in one.

Below is where we started at the beginning of December.  Remember how floody it was in northern Cal and Oregon?  That’s what can happen if a trough bowl stagnates just to your west (but not too far), since most of the rising air is to the east of the “bottom” of the bowl (where the arrows point roughly).

And, being away from the core of the jet stream at this level, us Catalina-ites experienced day after day of zephyrs moving 75-80 F air around in the afternoons.  Not bad really.  But change is good.

Arrows denote bowl troughs, where the “average” position is. There might be one there in central Asia, too.

 

Well, them days of stagnation, a “Snow Bird” paradise, and really wasn’t that bad if we coulda only had some rain, is gone.  Here’s what ahead:

Arrows denote roughly the bottom of trough bowls where storms collect.

 

Weather will change, as you already know from our TEEVEE people who make a LOT of money, from stagnant to vibrant, winds and storms from time to time as the trough bowl develops in the West.

Trough bowls are like repositories for storms, and around the globe there are typically 4-5 of them, waves in the westerly jet stream whose apexes mark the “bowl”.  Storms dip down into them from the northwest and then shoot out to the northeast, usually with lots of precip, after reaching the “bottom”, the most southerly extension of the bowl.

As you can see, we are a bit toward the west side of this bowl and that means the storms will be cold ones coming from the Pacific Northwest, at least to begin with.  Also, coming from that direction, they’ll be a bit rain challenged for us.

Mods still have a trace of rain on the 13th associated with the first storm to “fall” into the Bowl from the northwest, preceded by a dry cold front passage tomorrow.  Bundle up, it’ll be a very noticeable dry front passage with good northerly winds here in Catalina.

In the longer term, the “bowl” shifts farther to the West and there are actually some rain days showing up in the 10-15 day period.  But, as we know, unless they are supported by some spaghetti, those predictions are dicey, and they’re not well supported =s not too reliable.  Still, hope springs eternal, or at least until the next model run.

The End.

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1Maybe more teams should get to go to bowl games,not just the elite teams….as was posited long ago for the NCAA basketball tournament by Jesse Jackson in a presidential candidate debate of 1988 on NPR’s,  “At Loggerheads.”  Here, Jesse and George Herbert Walker Bush, debate how many teams should be invited to the NCAA basketball tournament.  Harry Shearer moderates: At Loggerheads

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.