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Found this burried deep in the forum. Did WRF-ARW ever get the gust calculation ?

I found some very old code on the WRF User's Forum: https://forum.wrfforum.com/viewtopic.php?f=8&t=948
from Robert Rosumalski.

SUBROUTINE CALGUST(LPBL,ZPBL,GUST)
C$$$ SUBPROGRAM DOCUMENTATION BLOCK
C . . .
C SUBPROGRAM: CALGUST COMPUTE MAX WIND LEVEL
C PRGRMMR: MANIKIN ORG: W/NP2 DATE: 97-03-04
C
C ABSTRACT:
C THIS ROUTINE COMPUTES SURFACE WIND GUST BY MIXING
C DOWN MOMENTUM FROM THE LEVEL AT THE HEIGHT OF THE PBL
C
C
C PROGRAM HISTORY LOG:
C 03-10-15 GEOFF MANIKIN
C 05-03-09 H CHUANG - WRF VERSION
C 05-06-30 R ROZUMALSKI - DYNAMIC MEMORY ALLOCATION AND SMP
C THREAD-SAFE VERSION
C
C USAGE: CALL CALGUST(GUST)
C INPUT ARGUMENT LIST:
C NONE
C
C OUTPUT ARGUMENT LIST:
C GUST - SPEED OF THE MAXIMUM SFC WIND GUST
C
C OUTPUT FILES:
C NONE
C
C SUBPROGRAMS CALLED:
C UTILITIES:
C H2V
C
C LIBRARY:
C COMMON -
C LOOPS
C OPTIONS
C MASKS
C INDX
C
C ATTRIBUTES:
C LANGUAGE: FORTRAN 90
C MACHINE : CRAY C-90
C$$$
C
C
use vrbls3d
use vrbls2d
C
C INCLUDE ETA GRID DIMENSIONS. SET/DERIVE PARAMETERS.
C
!
INCLUDE "params"
C
INCLUDE "CTLBLK.comm"
C
C DECLARE VARIABLES.
C
INTEGER :: LPBL(IM,JM)
REAL :: GUST(IM,JM)
REAL ZPBL(IM,jsta_2l:jend_2u)
C
C
C*****************************************************************************
C START CALMXW HERE.
C
C LOOP OVER THE GRID.
C
DO J=JSTA,JEND
DO I=1,IM
! GUST(I,J) = SPVAL
GUST(I,J) = 0.
ENDDO
ENDDO
C
C ASSUME THAT U AND V HAVE UPDATED HALOS
C
!$omp parallel do
!$omp& private(ie,iw,mxww,u0,v0,wind)
DO 20 J=JSTA_M,JEND_M
DO 20 I=2,IM-1
L=LPBL(I,J)
IF(MODELNAME .EQ. 'NMM')THEN
IE=I+MOD(J+1,2)
IW=I+MOD(J+1,2)-1

USFC=D25*(U10(I,J-1)+U10(IW,J)+
X U10(IE,J)+U10(I,J+1))
VSFC=D25*(V10(I,J-1)+V10(IW,J)+
X V10(IE,J)+V10(I,J+1))
SFCWIND=SQRT(USFC**2 + VSFC**2)
U0 = D25*(U(I,J-1,L)+U(IW,J,L)+
X U(IE,J,L)+U(I,J+1,L))
V0 = D25*(V(I,J-1,L)+V(IW,J,L)+
X V(IE,J,L)+V(I,J+1,L))
WIND=SQRT(U0**2 + V0**2)

ELSE IF(MODELNAME .EQ. 'NCAR')THEN
USFC=U10(I,J)
VSFC=V10(I,J)
SFCWIND=SQRT(USFC**2 + VSFC**2)
U0=U(I,J,L)
V0=V(I,J,L)
WIND=SQRT(U0**2 + V0**2)
END IF
DELWIND=WIND - SFCWIND
ZSFC=FIS(I,J)*GI
DELWIND=DELWIND*(1.0-AMIN1(0.5,ZPBL(I,J)/2000.))
GUST(I,J)=SFCWIND+DELWIND
10 CONTINUE
20 CONTINUE

C END OF ROUTINE.
C
RETURN
END
 
 
@dudhia

Code:
wrfout = Dataset('path/to/wrfout.nc')

frame = wrf.ALL_TIMES

wspd_wdir10 = wrf.getvar(wrfout, 'wspd_wdir10', timeidx=frame)
wspd_wdir = wrf.getvar(wrfout, 'wspd_wdir', timeidx=frame)
pblh = wrf.getvar(wrfout, 'PBLH', timeidx=frame)
height = wrf.getvar(wrfout, 'height_agl', timeidx=frame)
u10 = wrf.getvar(wrfout, 'U10', timeidx=frame)
v10 = wrf.getvar(wrfout, 'V10', timeidx=frame)
wrfout.close()

wspd_pblh = wrf.interplevel(wspd_wdir, height, pblh)                                               # 1.
g_pblh = np.where(pblh <= 1000, pblh, 1000)                                                          # 2.
G = (wspd_wdir10[0] + (wspd_pblh[0] - wspd_wdir10[0])*(1-(g_pblh/2000)))*3.6    # 3. gust in km/h

I have attached the complete script to this email.

_________________________________________________

Download

Matías

1709036270986.png
From the WRF-Python Forum
Credit to Matias Suarez
 
I think different definitions of a windgust exist depending on it's use. I would say a sudden brief increase in windspeed at a certain pressure level. It would be nice to be able to determine the maximum windspeed over all time steps within a certain time period/interval. Have you seen any code for this?
 
I think different definitions of a windgust exist depending on it's use. I would say a sudden brief increase in windspeed at a certain pressure level. It would be nice to be able to determine the maximum windspeed over all time steps within a certain time period/interval. Have you seen any code for this?
@Michel

Personally no, but it doesn't mean it isn't there.
If we can get some people to test this python code and then show that it works, we can hopefully get it implemented into WRF as a registry file.

Then once it is in there doing what you want should be pretty easy I think
 
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