Model Diagnostic Discussion NWS Weather Prediction Center College Park MD 340 AM EDT Sun Mar 08 2020 Valid Mar 08/0000 UTC thru Mar 11/1200 UTC ...See NOUS42 KWNO (ADMNFD) for the status of the upper air ingest... 00Z Model Evaluation with Preferences and Confidence ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ...Overall Pattern Across the CONUS... ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Preference: General model blend Exception: ECMWF/CMC/ECENS blend western US day 2/3 Confidence: Slightly above average 07Z update: With the rest of the 00Z guidance now available, there are not any major differences noted, particularly for the central/eastern U.S. where the previous WPC preference for a general model blend should still be sufficient. Across the western/southwestern U.S. associated with the upper level low, the spread in the mass fields has lessened. However given some of the QPF trends, the ECMWF is still favored and heavily weighted on day 3. Models exhibit fairly decent agreement with their mass fields across the central/eastern U.S. over the next few days. Aloft, troughing over the eastern/northeastern U.S. will be replaced with ridging/southwesterly flow into early next week. An impulse pushing into the central Plains Monday/Monday night quickly lifts into the Great Lakes region. While the 00Z GFS/NAM might be slightly more progressive in the eastward progression of the shortwave / surface low, the differences are relatively minor such that a general model blend should suffice. More substantial differences are apparent out west with the approach of a large closed upper low toward southern California on Tuesday. The bias from the past several model cycles is for the GFS/NAM to be on the faster side of the model spread and the 00Z guidance still shows that. Though the differences seem less apparent than previously noted. The most consistent run to run model has been the ECMWF, and for the WPC preference, it's favored heavily on day 2/3. Some inclusion of the UKMET/CMC as well as ECENS mean can be incorporated. Model trends at www.wpc.ncep.noaa.gov/html/model2.shtml 500 mb forecasts at www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml Taylor