[Met_help] question about the pcp_combine

[John Halley Gotway]

Ming,

Yes, that's correct.  In MET, when comparing a gridded forecast field to a gridded observation or analysis field, it is your responsibility to first place the data on the same domain.  Generally, it's
advised to regrid the forecast data onto the grid of the observation data, but you're welcome to do whichever you like.

Stage IV precipitation data is available through NCEP-EMC in GRIB format.  Please check here: http://www.emc.ncep.noaa.gov/mmb/ylin/pcpanl/stage4/
And look toward the bottom of the page for the section on "Where to get NCEP Stage IV".  I'm not sure if this is the same as CPC StageIV or not, but hopefully it'll meet your needs.

And we suggest using the "copygb" utility for regridding these GRIB files.  Copygb is one of the tools included in the WRF Post-Processor but may also be downloaded and built independently of WPP.

Hope that helps.

John Halley-Gotway
johnhg at ucar.edu

Ming Chen wrote:
> Dear Sir/Madam,
> 
> I am writing to ask about the observation precip you used in 
> pcp_combine. If I want to verify WRF precip simulation, I must have the 
> observation of precip at the same domain and grid as WRF does, is this 
> correct?
> 
> Now my question is, if I have CPC Stage IV precipitation data, but these 
> data are not GRIB format and not in WRF domain/grids, what tool can I 
> use to transfer these data before I can use them in pcp_combime/mode for 
> WRF precip verification?
> 
> I appreciate your suggestions and help!  Thanks in advance.
> 
> Ming
>