Model Diagnostic Discussion NWS Weather Prediction Center College Park MD 1211 AM EDT Thu Mar 28 2019 Valid Mar 28/0000 UTC thru Mar 31/1200 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: Non-NAM blend...Central/Eastern U.S. 00Z NAM/GFS and 12Z ECMWF blend...Western U.S. Confidence: Slightly above average The models are in good agreement in gradually weakening a deep layer closed low offshore the West Coast over the next couple of days. A portion of this closed low will separate off to the east and inland across the northern Great Basin and northern Rockies by Friday. This energy will then eject southeast across the central Plains Friday night and get caught up into the base of an amplifying northern stream trough over the Midwest through Saturday. Although some trailing energy/troughing related to the closed low is expected get left behind back toward the central Rockies underneath a deep layer closed high center that drops southeast from southwest Canada. Overall, the 00Z NAM gets to be a bit deeper than the global models with the northern stream trough evolution which ends up supporting a bit stronger wave development along an attendant frontal zone moving through the OH Valley by late Saturday and toward the East Coast on Sunday. Will prefer a consensus of the slightly less amplified global models which will include the details of the surface wave and frontal timing. By early Sunday, all of the guidance generally agrees with a weak trough or closed low feature setting up over the Four Corners region. The 00Z NAM/GFS and 12Z ECMWF are a bit better defined with the closed low, versus a somewhat weaker 12Z CMC/UKMET camp. The latest GEFS and ECENS suites tend to favor a modestly stronger closed low feature over the region by the end of the period, so will prefer a blend of the 00Z NAM/GFS and 12Z ECMWF with the evolution of this feature. Model trends at www.wpc.noaa.gov/html/model2.html 500 mb forecasts at www.wpc.noaa.gov/h5pref/h5pref.shtml Orrison