Model Diagnostic Discussion NWS Weather Prediction Center College Park MD 118 AM EST Sat Feb 29 2020 Valid Feb 29/0000 UTC thru Mar 03/1200 UTC ...See NOUS42 KWNO (ADMNFD) for the status of the upper air ingest... 00z Model Evaluation with Preferences & Forecast Confidence ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ NAM/GFS initialization errors do not seem to degrade their short range forecasts. System slowly pulling away from the Northeast through Sunday System moving through southern Canada & trailing front Sat/Sun System dropping down toward US/Canadian border Mon/Tue ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The guidance shows good agreement with these features. A compromise of the 00z UKMET, 00z Canadian, 00z NAM, 00z GFS, and 00z ECMWF is preferred with above average confidence. System dropping down the West Coast Sunday & Monday ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Preference: Non-GFS compromise Confidence: Slightly above average Starting on late Sunday, the 00z GFS is more eastward aloft than the other guidance, which appears to be due to a slightly weaker northern stream ridge moving over the top of the system. The non-GFS guidance has been fairly stable showing a system moving near and offshore the CA coast over their past day of runs, which fits conceptual models considering the building ridging to its north forcing the mid- to upper-low southward and a lack of an upstream kicker shortwave. A compromise of the 00z NAM, 00z UKMET, 00z Canadian, and 00z ECMWF is advised with slightly above average confidence. Model trends at www.wpc.ncep.noaa.gov/html/model2.shtml 500 mb forecasts at www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml Roth