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Message: Re: CAPE change in RUC2

Posted by John B. on 4 May 98, 15:08 MT, in response to Re: CAPE change in RUC2, posted by Michael Dross on 3 May 98, 21:52 MT

As a result of having to back out the latest change to the calculation of
CAPE and CIN (see Kevin Brundage's message of a couple weeks ago), and
subsequent conversations with Phillip Bothwell that helped to pinpoint some
additional problems with the present calculation, I am in the process of
substantially revising the present CAPE-CIN calculation. When its done (in a
day or two) the new version will need to be tested at FSL and compared with the
old one before it is put in at NCEP. Implementation of the new CAPE-CIN
code at NCEP will thus not happen for a few days at least; we will send out another message when this is scheduled, and also will send out a description
of the new procedure and how it differs from the old one.

Presently, the CIN values are too large, particularly when the mixed layer
is deep, as is typical during the afternoon on the High Plains. Other
deficiencies in the present calculation, including the problem in
locating the LFC, leading to "holes" in regions of large CAPE, are also being
addressed in the new version. We regret that these problems weren't recognized
earlier, before the heart of the convection season.

... John M. Brown

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