Model Diagnostic Discussion NWS Weather Prediction Center College Park MD 1138 AM EST Fri Jan 10 2020 Valid Jan 10/1200 UTC thru Jan 14/0000 UTC ...See NOUS42 KWNO (ADMNFD) for the status of the upper air ingest... 12Z Model Evaluation with Preferences and Forecast Confidence ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ...Overall Pattern Across the CONUS... ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Preference: General model blend Exception: Non-CMC central Rockies to central Plains after 12.12z Confidence: Slightly above average The latest model guidance continues to converge on a similar solution with respect to the overall large scale pattern across the CONUS through the next 3 days. Anomalously shortwave trough currently digging across the southwest U.S. will eject out into the southern Plains today with its corresponding surface low deepening as it lifts northeast. This feature will lift along a wavy stationary boundary draped from portions of the Plains northeast toward the southern Great Lakes. Through the next 48 hours, model heights and mass fields are tightly clustered between all the major global deterministic guidance and differences lie mainly in the mesoscale, hi-res models regarding specific timing/evolution of the convective elements. Beyond 48 hours as the low lifts across the Northeast, some timing differences are noted with the GFS racing out ahead of the other, non-NCEP models but given the run to run trends, this may not be too out of tolerance. So overall for the central/eastern U.S. storm system, a general model blend should suffice. For the western U.S. shortwaves, a couple compact systems will affect the Pacific Northwest where the CMC remains the outlier. Its slow/lagging solution becomes more apparent after 12.12Z as the initial shortwave reaches the central Rockies toward the central Plains where it's noticeably slower than the rest of the deterministic guidance. In its wake, another shortwave drops through the northwest where the GFS/ECMWF appear fairly tightly clustered with just minor timing differences noted. With all this in mind, leaned toward a general model blend across the CONUS outside of a non-CMC blend after 12.12Z particularly across the central Rockies to central Plains. Model trends at www.wpc.ncep.noaa.gov/html/model2.shtml 500 mb forecasts at www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml Taylor