Model Diagnostic Discussion NWS Weather Prediction Center College Park MD 342 AM EDT Mon Sep 02 2019 Valid Sep 02/0000 UTC thru Sep 05/1200 UTC ...See NOUS42 KWNO (ADMNFD) for the status of the upper air ingest... 00Z Final Model Evaluation, Confidence, and Preferences ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ...Overall Pattern Across the CONUS... ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Preference: Non-NAM blend Confidence: Average 07Z Update: The Non-NCEP 00z Suite showed little change from the 12Z, so the preferences remain unchanged. The UKMET may be a bit amplified compared to the consensus in the depth of the shortwave moving across the northern tier, but remains well within the ensemble envelope so can continue within the preferred blend. Previous Discussion: The models are in good agreement that the longwave synoptic pattern will maintain a ridge in the west and a trough in the east. There is little variation in the guidance, and the features determining the preferred blend are generally smaller scale. The NAM deepens the eastern trough a little too much when compared to the global consensus. and is also much flatter with heights across the NW. Otherwise, the 00Z GFS and 12Z Non-NCEP suite are well clustered despite small temporal differences in a shortwave moving eastward from the PacNW into the northern tier. Despite these differences, QPF fields are well aligned so a blend which includes all of the global suite except the NAM is reasonable. ...Hurricane Dorian... ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Please refer to the official National Hurricane Center forecast track A blend of the 00Z ECMWF/00Z UKMET/00Z GEFS mean provides the best proxy to the 03Z NHC advisory track. The 00Z GFS deterministic is very closely tied to the track through 48-60 hours, but then becomes a bit fast and left of the track, while the GEFS mean remains nearly on top of the forecast points, so is preferred more than the operational run. Model trends at www.wpc.noaa.gov/html/model2.html 500 mb forecasts at www.wpc.noaa.gov/h5pref/h5pref.shtml Weiss