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>From: Lodovica Illari <address@hidden> >Organization: UCAR/Unidata >Keywords: 200209101900.g8AJ0u111309 >Hi, > >I use the ldm to ingest RUC data. I have tried dcgrib to convert it to a >gempak file but it gives me the following error message: > >Sep 10 17:56:24 dcgrib[14772]: Starting Up >Sep 10 17:56:24 dcgrib[14772]: Invalid center id/grid id >combination: 7 236/disk20/data/ldm5/gempak/n >ps/02091015.ruc_gem >Sep 10 17:56:24 dcgrib[14772]: can't open file >/disk20/data/ldm5/gempak/nps/02091015.ruc_gem >Sep 10 17:56:24 dcgrib[14772]: Exiting >Sep 10 17:56:24 dcgrib[14772]: 1 WMO msgs, 1 GRIBs decoded, 0 written > > >What do I need to do? > >Please note that I use gempak 5.4. > >Thanks > >Lodovica Illari > > Lodovica, There are several different RUC grid projections in the data stream (grid 211 is the 80km, grid 236 is the 40km, and in the future at grid 252 is the 20km). All grids in a single grid file must have the same projection. The likely cause of the above message is that the file has been created when an 80km grid was received, and now a grid 236 40km grid is trying to be written to the same file. You need to have unique file names for the different projections. You can do this by making specific pqact.conf entries for each RUC projection for dcgrib, or I provided a newer program called dcgrib2 that can replace a template "@@@" with the grid number. For dcgrib2, you could simply send all ruc data to the decoder with an output file name of YYYYMMDDHH_ruc@@@.gem. For dcgrib, separating each grid projection by WMO would look like: ^[YZ].Q... KWBG --> YYYYMMDDHH_ruc211.gem ^[YZ].W... KWBG --> YYYYMMDDHH_ruc236.gem Steve Chiswell