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Hi Kevin, If I understand you correctly, you are overlaying surface data on top of radar image files by calling multiple instances of GPMAP in a script. Unfortunately there's no easy way to accomplish what you want: to generate surface data overlays once once per hour while generating radar image layers more often. A more labor-intensive option may be: Create surface map files (gif) once per hour in the cron and in the same script file make a call to the ImageMagick program 'convert' to set a single color transparent: "convert surface.gif -transparent black surface-transparent.gif" and then overlay this transparent gif on top of the more frequently made radar images with another called to convert in the radar generation shell script: "convert radar.gif surface-transparent.gif -compose over plot.gif" where plot.gif is the final product. This method requires the image/data projections be identical or it simply won't look correct - it uses programs outside of GEMPAK and will take some experimentation to get right if you choose to play around with it. Michael James Unidata User Support > Hi, > > I have a question/problem I am trying to figure out and need some help. I > am running a script which creates a radar images of certain areas and > uploading that to a webpage. I am also creating overlay graphics for the > same areas (i.e., sfcplot, heights, wind contours, instability, etc). The > problem is I have my script creating the overlays every time the radar > script runs, which is several times an hour. I only need the overlays once > an hour. I am not sure how to create the overlays just once per hour > without the radar image. I want to keep it in the radar projection (proj = > rad). But how can I make an overlay using GPMAP with the radar image not > showing? I just want the background map and then I can overlay it onto the > radar images I have in my loop. Right now the way my script reads is I > create the radar image, then using the same projection and garea...I create > the overlays using the clear=no option. Obviously this is not the most > efficient way to do this....so if you can assist me I would really > appreciate it. Thanks. > > Kevin > Ticket Details =================== Ticket ID: WUQ-124584 Department: Support GEMPAK Priority: Normal Status: Open