Model Diagnostic Discussion NWS Weather Prediction Center College Park MD 1249 PM EDT Fri Jun 07 2019 Valid Jun 07/1200 UTC thru Jun 11/0000 UTC ...See NOUS42 KWNO (ADMNFD) for the status of the upper air ingest... 00Z Model Evaluation...with Confidence and Preference ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ...Overall Pattern Across the CONUS... ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Preference: 12Z NAM, 12Z GFS, 00Z ECMWF blend Confidence: Average There will be two main upper level systems to affect the lower 48 through Monday. The first is a slowly weakening closed low moving east from the lower Mississippi Valley into the Tennessee Valley while becoming more elongated from north to south. The other system will come in the form of a progressive shortwave at the leading edge at the base of a longwave trough over central Canada into the northern U.S. There is general model agreement with the system affecting the Southeast. Regarding the system moving through the north-central U.S. on Sunday and the Great Lakes on Monday, there are two camps in the latest deterministic guidance. The 00Z ECMWF/UKMET are a bit more amplified and wind up with a strong negative tilt at 500 mb over the Great Lakes on Monday. The 12Z NAM/GFS and 00Z CMC are weaker and slower to acquire a negative tilt. The surface evolution also differs correspondingly with a more westward track seen in the 00Z ECMWF/UKMET. The 12Z GFS is toward the weaker side of the models with the surface low. Given no significant ensemble clustering or trends, the preference is to lean toward the middle with a 12Z NAM, 12Z GFS and 00Z ECMWF blend recommended. Model trends at www.wpc.noaa.gov/html/model2.html 500 mb forecasts at www.wpc.noaa.gov/h5pref/h5pref.shtml Otto