Model Diagnostic Discussion NWS Weather Prediction Center College Park MD 102 AM EDT Sun Jun 07 2020 Valid Jun 07/0000 UTC thru Jun 10/1200 UTC ...See NOUS42 KWNO (ADMSDM) for the status of the upper air ingest... 00Z Model Evaluation Including Initial Preferences and Confidence ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ...Closed low over the Pacific Northwest swinging across the northern Rockies late today... ...Associated upper trough moving from the Great Basin to the Great Plains tonight through Tuesday... ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Preference: Non-GFS/NAM blend Confidence: Average While the general pattern of the upper low swinging east from the Pacific Northwest today lifting across northeast Montana into Saskatchewan on Monday there are strength issues. The 00Z NAM and GFS keep a closed low across the Rockies into MT and the GFS/18Z GEFS further strengthen the low over Saskatchewan on Monday while non-NCEP guidance opens the low over the ID/MT Rockies tonight and keeps a trough axis over the northern Plains through Monday night before absorbing Cristobal remnants. This stronger low/trough over the northern Plains in the NAM/GFS pushes the trough farther east which makes for convergence/predecessor rain from Cristobal farther east over the north-central Plains on Day 2 than non-NCEP guidance. Particularly with the GFS, the eastern favoring brings Cristobal remnants farther north quicker. Will have to see what the non-NCEP guidance does with 00Z runs to have a full-handle and the final preference may change. ...Cristobal... ~~~~~~~~~~~~~~~~~~ Preference: 03Z NHC advisory Confidence: Refer to NHC products The 03Z NHC track is on the faster side of the global sfc low center progs with only the 00Z GFS outpacing it through the Day 3 time frame. As noted above the GFS is the fastest solution with Cristobal, likely due to a stronger low over the Canadian Prairies Monday shunting the trough farther east with an earlier interaction with Cristobal than the rest of the guidance. The 12Z UKMET takes the slowest turn across the mid Mississippi valley toward the Great Lakes. The 12Z ECMWF has shifted east and shows good agreement with other non-NCEP guidance, just a little slower than the NHC track. Model trends at www.wpc.ncep.noaa.gov/html/model2.shtml 500 mb forecasts at www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml Jackson