Model Diagnostic Discussion NWS Weather Prediction Center College Park MD 250 PM EST Sat Dec 21 2019 Valid Dec 21/1200 UTC thru Dec 25/0000 UTC ...See NOUS42 KWNO (ADMNFD) for the status of the upper air ingest... 12Z Model Evaluation with Preference and Forecast Confidence ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ...Overall Pattern Across the CONUS... ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Preference: 12Z GFS/ECMWF blend Confidence: Slightly Above Average 20Z update: No significant changes noticed with the rest of the 12Z guidance and the GFS/ECMWF blend is still preferred. ---previous discussion--- Forecast models are in fairly good agreement with the overall synoptic pattern and mass fields across the CONUS during the next 3 days. The closed low over Oklahoma will deepen and expand as it moves to the FL Panhandle by early next week. The global deterministic guidance has converged on a similar timing and strength at 500 mb. Even at the surface, the spread between the various low tracks/centers has lessened and the ensemble plots also show lessening spread through 84 hours. Out West, an active and unsettled flow pattern will remain in place through the forecast period, with various shortwave troughs moving through the longwave trough. But in general there is good agreement on the timing and strength, with some variations seen in the QPF. Overall, a blend of the GFS and ECMWF is preferred for the CONUS this cycle. Model trends at www.wpc.ncep.noaa.gov/html/model2.shtml 500 mb forecasts at www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml Taylor