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Use WRF Output as WRF input using UPP


New member
I'm trying to use WRF output as WRF input for a higher resolution grid using UPP. The reason for doing this is that it should mean that I don't need to keep the even higher resolution data as well, but just my lowest grid WRF output.

I have tried a number of tables for UPP and WRF that are both within the params folder for UPP and the Variable_Tables for WPS. All seems to go ok until I get to metgrid where it tells me that I have no pressure readings on the lower levels. It seems that there is a magic combination of tables for UPP and WPS to ensure that the ungribed data has all the information required, but I can't work out what the combination is.

Is anyone able to let me know please?
I was trying to use version 4, but none of the tables available with UPP / WPS or those from the forums would produce an input that WPS was happy with.

I found a workaround, although not a elegant, you can use the first 2 hours of the data that you used to generate your outer grid. Then run real for this 2 hour period, then ndown for the full period and then WRF following the instructions in the userguide. This then uses the outer grid the source for the inner grid and doesn't require the storage of too much additional data.
We did have some contributions (12th FAQ in that list) of parameter files/tables that you can look at, with a procedure to follow to do this. I believe they were contributed with an earlier version of UPP than v4, but you might still find them to be helpful.