[Wswss] Rare visual inversion, San Joaquin Valley

kr7o at vhfdx.com kr7o at vhfdx.com
Thu Oct 23 11:53:40 EDT 2008


This morning at 1505Z I saw my first ever (over land) visual inversion 
while driving to work.  I noticed something strange on the western 
horizon.  There was a strong horizontal line about 1 degree above the 
horizon.  I could not see the coast range about 60 miles away (which I 
usually can from my QTH), but could see the top of the normal valley 
inversion layer (with blue sky above).  Looking at the line I realized I 
was seeing the inverted images of trees etc., just above the 
horizon.  Today should provide some unusual conditions for 10Ghz and up 
propagation on the valley floor and possibly in the inversion.  I wonder if 
what I saw was actually the upper and lower boundry of a duct.  Needless to 
say, this is a very rare event.  I have never heard reports of a visual 
inversion in the SJV.

I have only ever experienced one other visual tropo event off the SoCal 
coast where I saw Catalina floating a degree or two above the horizon, but 
not inverted.

Unfortunately, I didn't have a camera with me, but did call my wife.  Will 
see when I get home if she was able to get any pictures.  I will check 
again after sunrise tomorrow for a rare repeat.


73, Robert KR7O/YB2ARO, DM07ba/OI52ee  (ex.  N7STU)
kr7o at vhfdx.com

www.vhfdx.com (KR7O/YB2ARO homepages)





More information about the Wswss mailing list