<HTML><BODY style="word-wrap: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space; ">Assuming that areas of snow, rain, and freezing rain do not overlap, you could draw the first field (snow), then print the image to a file in the .png format. Next, you draw the second field (rain), but this time when you print the image to a file, you use the -b option to include your first plot in the background, and also use the -t option so that the areas of no rain would be transparent. Finally, you draw your third field (freezing rain), and print it using the -b option with the 2nd .png image file you created and the -t option with the transparent color belonging to the no-freezing-rain color. When you're done, you should have three layered images, with the middle and top images having a transparent color that allows the bottom and middle images to show through where there is no rain or freezing rain. I think the -t and -b options were added during the development of version 1.9, so this strategy won't work if you're using version 1.8.<DIV>Jennifer</DIV><DIV><BR class="khtml-block-placeholder"><DIV><BR class="khtml-block-placeholder"></DIV><DIV><BR><DIV><DIV>On Dec 6, 2006, at 6:23 AM, Alessandro Mandelli wrote:</DIV><BR class="Apple-interchange-newline"><BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Dan Leins ha scritto:</DIV> <BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">All,</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">I would like to create an image using GrADS of 3 separate model fields,</DIV> </BLOCKQUOTE><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">I have the same question and the same problem.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">The only solution I could come up with is</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">d snow + rain*100 + freezingrain*10000</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">and associate three colors to 1, 100 and 10000 but I'm not really happy</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">with that.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Cheers</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV> </BLOCKQUOTE></DIV><BR><DIV> <SPAN class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><DIV>Jennifer M. Adams</DIV><DIV>IGES/COLA</DIV><DIV>4041 Powder Mill Road, Suite 302</DIV><DIV>Beltsville, MD 20705</DIV><DIV><A href="mailto:jma@cola.iges.org">jma@cola.iges.org</A></DIV><DIV><BR class="khtml-block-placeholder"></DIV><BR class="Apple-interchange-newline"></SPAN> </DIV><BR></DIV></DIV></BODY></HTML>