All QPF products were interpolated to the RFC 4km (HRAP) grid (except that HR-PW and HR-CONT QPFs are not
interpolated since the HRAP grid is native for these products). QC'd RFC 4km QPE data (~462,000 gridpoints over CONUS)
were used for validation. A rigorous machine-human interactive process was used to perform QC at MDL
wherein about 6% of QPE data was discarded during warm season and 12% during cool season. Subjective
and objective comparisons of the QC'd QPE data and QC'd gage precipitation data shows very good
consistency between the two precipitation data types.
RFC QPFs are not
included in the scoring because of their limited issuance times and forecast projections.