Next 3 days forecast
- Thread starter Deepu2006
- Start date
haiqingsong
Member
Using GFS forecasting data to drive your WRF.
You should make sure to download the forecast data for the entire time period you plan to run. Then you set your namelist dates and times to the full time, as well. Other than that, there is nothing different you need to do to run a future forecast, vs. a past time.
Thanks for your reply @kwerner
Like I have downloaded gfs.0p25.2024060900.f072.grib2 this data which is 72 hours forecast and I want to run next 3 days forecast using that.....what change i have to do in namelist
Like I have downloaded gfs.0p25.2024060900.f072.grib2 this data which is 72 hours forecast and I want to run next 3 days forecast using that.....what change i have to do in namelist
William.Hatheway
Active member
@Deepu2006
So WRF, as a regional weather model does not create forecasts in the way that global forecast models do. WRF uses the global forecast models as boundary conditions and then applies its own physics and dynamics to the boundary conditions to make the forecast. So if you want WRF to do a forecast for for 6 days, you need to download 6 days worth of forecast boundary files from GFS to run it. Otherwise the WRF model will stop at the end of the data.
So WRF, as a regional weather model does not create forecasts in the way that global forecast models do. WRF uses the global forecast models as boundary conditions and then applies its own physics and dynamics to the boundary conditions to make the forecast. So if you want WRF to do a forecast for for 6 days, you need to download 6 days worth of forecast boundary files from GFS to run it. Otherwise the WRF model will stop at the end of the data.
@Deepu2006
You shouldn't download just a single-time data. For the 3-day forecast you intend to do, you will download data at 3-hr or 6-hr intervals over that 72-hr period, i.e., you should obtain gfs.0p25.2024060900.f000.grib2, gfs.0p25.2024060900.f006.grib2, gfs.0p25.2024060900.f012.grib2, etc. Then ungrib these data, run methrid.exe and real.exe to produce initial and lateral boundary forcing data, and move on to run wrf.exe.
You shouldn't download just a single-time data. For the 3-day forecast you intend to do, you will download data at 3-hr or 6-hr intervals over that 72-hr period, i.e., you should obtain gfs.0p25.2024060900.f000.grib2, gfs.0p25.2024060900.f006.grib2, gfs.0p25.2024060900.f012.grib2, etc. Then ungrib these data, run methrid.exe and real.exe to produce initial and lateral boundary forcing data, and move on to run wrf.exe.
So if i want to run a forecast, should i always start from the gfs.0p25.2024060900.f000.grib2 file? If i am using files from gfs.0p25.2024060900.f072.grib2 to gfs.0p25.2024060900.f144.grib2, it should work right? but in the namelist i would be using 12 june 2024 as the inital date and 15 june 2024 as the end date. that is how i should set the namelist as well. is that right?