Thickness approaching 600 dam (not here)
 

This is Ahwaz, Iran. See
http://weather.uwyo.edu/cgi-bin/soun...500&STNM=40811

I think this is the highest 1000-500 mb thickness I have seen on
one of these charts. The current surface temp is 47. Does anyone know
the highest thickness that has been reliably measured, allowing if
necessary a *little* extrapolation to sea-level. It must exceed 600
dam, I should think.

Tudor Hughes, Warlingham, Surrey.