National Precipitation Verification Unit

1. National Precipitation Verification Unit NDFD 32km and 4km verification implementation By: Letitia Soulliard March 8, 2005

2. A Brief History of the NPVU • Started Operating October 1, 2000 • Initially just had scores for the Eastern RFCs • Added the Western RFCs in Nov, 2000 and Jan, 2001 • Added Conus verification in Jan, 2001 • Added HPC mountain mapper verification in July, 2003 retroactive to Jan, 2003

3. Current NPVU Products • RFC 32km verification • 6-panel comparison plots of 6-hr QPE and QPF for each RFC domain • Daily updated RFC QPF, QPE and FFG graphics • Archive of RFC QPE and a months worth of HPC QPF

4. The NDFD Verification Plan • Continue with current RFC verification at 32km • Add WFO verification at 32km for historical consistency • Add WFO verification at 4km to assess skill at a comparable level to the NDFD 5km resolution • Add RFC verification at 4km for unity

5. Brief Description of Implementation Process • Started retrieving and archiving NDFD 00z, 06z, 12z, and 18z forecast on Sept. 22, 2004 • Verifying for 12Z forecast only • Remapped all of the Models, HPC, RFC, and NDFD data to the 4km hrap grid. • Cut the data down to each WFO area for verification.

6. Brief Description of Implementation Process • Found that the 12z NDFD QPF only went out to 60 not 72 so only verify for day1 and day2 • Expanded verification Intervals up to 4” for WFOs (RFCs are remaining the same) • Expanded web site to include new verification scores

7. Final Implementation and Future Plans • Correct Scaling issues for already run months • Catch verification up to current month • Announce that verification is up and ready and operational • Add Puerto Rico to the verification

8. Thank you • NPVU website: • http://www.hpc.ncep.noaa.gov/npvu • My e-mail: • letitia.soulliard@noaa.gov