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Gust speed lower than mean wind speed in NMM output


New member
Hi all,
I found that in the output of the NAM models by NCEP the gust speed is often significantly lower than the mean wind speed.
NAM uses the WRF-NMM dynamical core.
In terms of the grib output, I found

GUSTS < sqrt(UGRD**2 + VGRD**2)

I did not yet check if this is also the case for HRRR output, which uses the WRF-ARW dynamical core.
I wonder how NCEP diagnoses maximum wind speeds based on the output of NAM.
Can anyone help?