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<span class="postbody"><span style="font-size: 10pt; font-family:
"Trebuchet MS"; color: rgb(0, 0, 192);">Meredith,<br>
<br>
I ran into a similar problem while attempting to compute
condensation pressure deficit (CPD). My solution was to derive
an equation for my value of interest and then implement it in
GrADS. Deriving the equation was the most difficult portion of
this task. Once I had that in hand, I used several steps to
bootstrap the solution in GrADS. For example, my CPD equation
requires virtual temperature and the change in height by way of
the hypsometric equation. For one step, I calculate the virtual
temperature grid. In the next step I use the calculated virtual
temperature grid in the hypsometric equation to find the change
in height. For my way of thinking, a step-wise process, taking
each piece in a small chunk, is easiest to comprehend during the
testing phase. After you verify your solution works, you can
refine the method to improve your processing efficiency.<br>
<br>
In my experience, you can "define [var]=[eqn]" to create the
appropriate gridded variable. If you have x and y varying (for a
single time), you'll calculate the variable for each gridpoint
in your domain or vary x, y, and t for multiple time steps in
your domain.<br>
<br>
Hope this helps.<br>
<br>
</span></span>-- <br>
<div class="moz-signature"><span class="postbody"><span
style="font-size: 10pt; font-family: "Trebuchet MS";
color: rgb(0, 0, 192);">Kevin L. Huyck<br>
Forecaster, Meridian Environmental Technology, Inc.<br>
<a href="mailto:klhuyck@meridian-enviro.com">
klhuyck@meridian-enviro.com</a><br>
<br>
Composed using Mozilla Thunderbird!</span></span><br>
<span class="postbody"><span style="font-size: 10pt; font-family:
"Trebuchet MS"; color: rgb(0, 0, 192);"><br>
<br>
+++Begin copied text+++</span></span><br>
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<span class="postbody"><span style="font-size: 10pt; font-family:
"Trebuchet MS"; color: rgb(0, 0, 192);"><br>
Hi Everyone,<br>
<br>
I'm looking to plot a contour plot of LFC height, similar to the
graphic<br>
on the SPC Mesoscale Analysis page, my control file does not
output LFC<br>
directly, is there anyway I can calculate this in grads?<br>
<br>
Thanks for your help.<br>
<br>
Meredith<br>
+++End copied text+++</span></span><br>
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