Model Diagnostic Discussion NWS Weather Prediction Center College Park MD 323 PM EDT Fri Jun 15 2018 Valid Jun 15/1200 UTC thru Jun 19/0000 UTC ...See NOUS42 KWNO (ADMNFD) for the status of the upper air ingest... 12Z Model evaluation of all guidance...with final preferences ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ...Overall model diagnostic analysis for the CONUS... Preliminary preference: A blend of the 12Z GFS/ECMWF, although the 12Z UKMET is useful as well Forecast confidence: Above average outside of areas of mesoscale focus ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ...Primary features of interest between 15/1200Z - 19/0000Z... 1) Remnants of Tropical Depression Bud 2) Disturbance lifting out of the southwestern Gulf of Mexico 3) Mean upper low anchored over the Central Great Basin 4) Myriad of shortwaves rising out of the Four Corners into the north-central U.S. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ...Discussion... (1,2) On the large-scales, differences are minimal through at least Day 2 given fairly well clustered forecast solutions. Tropical Depression Bud weakens over the northern interior of Mexico with remnant vorticity and moisture pushing into the Four Corners and areas farther downstream. Remaining in the subtropics, an area of disturbed weather currently given a 10% probability for tropical cyclone development by NHC should lift toward the Texas coast the next couple of days. The 12Z NAM/CMC stand out as outliers forming a low center so plan on sticking with a surface trough at this point. (3,4) Considering the eventual upper low semi-permanently set up over the western U.S., decent synoptic-scale agreement is evident through roughly early Sunday. Eventually the 12Z NAM becomes too quick with the northern extent of the surface boundary across the Upper Great Lakes. While the 12Z CMC improved on its solution aloft here by not being as robust with the approaching trough, it does stand out as a slower/westward displaced outlier at the surface. Otherwise all other issues with the evolving pattern will be more on the mesoscale with differences numerous throughout the period. Model trends at www.wpc.ncep.noaa.gov/html/model2.shtml 500 mb forecasts at www.wpc.ncep.noaa.gov/h5pref/h5pref.shtml Rubin-Oster