<div dir="ltr">I am trying to plot a cross section of potential temperature (pressure x longitude). I followed a simple example here (<a href="https://www.ncl.ucar.edu/Applications/Scripts/mask_14.ncl">https://www.ncl.ucar.edu/Applications/Scripts/mask_14.ncl</a>) and modified it for my use. For some reason, when I create the mask, all values are reverted to the _FillValue, and I can't figure out why. My program is attached. Thanks.<br><br><br clear="all"><div><br>-- <br><div class="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div>Andrew Kren, PhD<br>
Research Scientist I, Global Observing Systems Analysis (GOSA) Group<br>
NOAA ESRL Global Systems Division (Rm 3C515)<br>
325 Broadway, Boulder, CO 80305<br>
<a href="tel:%28303%29%20497-5418" value="+13034975847" target="_blank">(303) 497-5418</a><span><font color="#888888"><br>
</font></span></div></div></div></div></div></div></div></div></div></div></div></div></div></div>
</div></div>