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(RESOLVED) What is the minimum value for the num_metgrid_levels

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Dear Colleges,

What is the minimum value for the num_metgrid_levels parameter lower that value the WRF model will fail to work?

Best regards,
Hi Artur,

I assume this question is related to your question here?

If so, is it okay if we delete this question?
If not, can you clarify exactly what you're asking?

Dear Kelly,

Indeed, this was another issue I faced. I had a forcing data with upper-air data available at 15 pressure-levels.
I thought that the stop of real.exe was because of insufficient number of vertical levels in my data.

Thank you for the clarification. We don't actually have a minimum of levels required to run WRF. The input data come with a set number of vertical levels and then, depending on what you set the number to when running real/wrf (e_vert), the model will just interpolate to however many levels you requested, using the data from the available levels from input. This is actually not always great practice, as sometimes the number of levels doesn't provide enough information between levels for a good interpolation. Unfortunately, it's just something each person will need to test - to make sure things look reasonable. I'd recommend running a short test with the set-up you're interested in and see whether it looks okay. 15 levels may be okay, but we typically see closer to 30 levels for basic input data.