NUCAPS first guess was not that representative of the atmosphere when sampling a clear air sounding. After altering, we went from 0 to 3500 J/kg of CAPE. Which we thought was a bit high.
We did the same thing for an area farther north where we are expecting more instability. First NUCAPS sounding before altering did show a little CAPE (a few hundred), and altering took it back to ~3000 J/kg, a few J/kg lower than the southern, more stable environment. -BT