Wind speed is required by SWAT+ when the Penman-Monteith equation is used to calculate potential evapotranspiration. Mean daily wind speed is generated in SWAT+ using a modified exponential equation:
μ10m​=μwndmon​∗(−ln(rnd1​))0.3 1.3.6.1
where μ10m​ is the mean wind speed for the day (m s−1), μwndmon​ is the average wind speed for the month (m s−1), and rnd1​ is a random number between 0.0 and 1.0.
Table 1:3-6: SWAT+ input variables that pertain to generation of wind speed.
WNDSIM
Wind speed input code: 1-measured, 2-generated
file.cio
WNDAV(mon)
μwndmon​: Average wind speed in month (m/s)
.wgn