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Hey there, Last time I wrote I was trying to create the hourly surface LI from the observed 12Z and 00Z 500 mb temps. Well, I have got that figured out and running pretty good. I am now into the next phase of trying to update the hourly surface LI's. I would like to use the ETA and the RUC to give me 500 mb temp grids at different intervals and then use that in place of the observed 500 mb temp grids . This should give me a a better representation of the hourly surface LI. As I said at first, the script runs good in creating the hourly surface LI with the observed 500 mb temps. I doi have to create it as a vgf file because I am not sure how to go about incorporating the part of the script that does the time/data calculations into a restore file (.nts). So I am stuck with the vgf format for now. But I have gotten off course just a little bit. I used the program GDCFIL to create a file(s) which I called "eta or ruc.grd". This file is the one in which I will store my 500 mb temperatures for that particular model. and then run the calculation with that grid instead of the observed temp grid. Well, I have it mostly but I am having a problem with the GDATTIM part. for instance my eta grid is stored as YYMMDDHH_eta_211.gem. When I tried GDATTIM the first time I thought I could just put in the date and time (ie; 12/11). Then I realized it was looking for the forecast time of the grid. So with the ETA when it is asking me for a time I am putting in F06 for GDATTIM. That worked and the grid was created. However, the problem is in how the grid is stored. It says when I looked at the grid with GDINFO that the grid (which I named ETMPC) was dated as 030511/12F006. That is where my problem is because of how the grid is dated. Is there a way to get around this? I thought I could just create this grid and subsititute in ETMPC for the TMPC in the regular script. But that doesn't seem to be working. I am wondering if there is any "operator error" involved in this whole process. Also, is there a way to make this LI script a restore file? I have tried but it doesn't like the setting of the different variables(ie, day, hour, etc). Thanks. Kevin Polston Senior Instructor, NWSTC Kansas City MO 64152 816-880-9314 ext 273