"Alastair McDonald"
.................................................. ......................
I am actually providing two solutions to the problem here. They
can't both be wrong!

Cheers, Alastair.


Unfortunately I think they are in this case-as splitting starts over the
open ocean.
When fronts interact with topography damming of the cold air can occur at
low levels and decouple from the flow aloft-but that is a different
phenomenon.
We're talking about an effect to due to the dynamics of the lower
stratosphere and upper to mid troposphere.
Unfortunately the analogy with breaking ocean waves only goes so far.
Overrunning of the dry air is particularly apparent in WV imagery,but is
also apparent in IR and VIS.
I'll try to find some references when I have the time later,

--
regards,
David

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