This site is an archive of model forecast precipitation vs. 24-h (12Z-12Z) observed precipitation analysis. Near the top of each day's page is an index of available comparisons (models and forecast lengths) for that day. Forecast lengths vary, but the accumulation period is always 12Z-12Z. For example, on 1 Dec 2001, the 06-30h forecast of the 10km Eta Western Nested run (which has a starting time of 06Z) was verified against the 12Z-12Z precipitation analysis.
Models being verified:
Log of changes
Log of problems