James Robinson wrote:
Brian Whatcott wrote:
Sounds plausible to me. A direct path from unexpected rain at high
altitude (warm massive updraft in cu-nim?) to ice to frozen pitots to
loss of rudder limiting.

This meteorologist suggests that it would be highly unlikely for the Air
France flight to have encountered rain or even supercooled water. He also
suggests that the cause, if any, would be from descending air warming
rather than an updraft:

http://www.weathergraphics.com/tim/af447/

I read this over carefully, a few days ago. It seems like a respectable
evaluation. And yes, it is highly unlikely situations which we are
addressing. Both the eye-witness testimony of a person observing
considerable precipitation at altitude, and the obvious meteorological
observation that the higher the air, the colder, and the dryer (in
absolute terms). If you accept this, then you have to accept that the
water can only have come from below, via meso scale uplift (as the
report puts it). That's not to say the uplift was not pulling water up
higher than the fatal flight, then dropping it. These buildups are
invariably turbulent.

Brian W