Model Diagnostic Discussion NWS Weather Prediction Center College Park MD 327 AM EDT Tue Jul 09 2019 Valid Jul 09/0000 UTC thru Jul 12/1200 UTC ...See NOUS42 KWNO (ADMNFD) for the status of the upper air ingest... 00Z Model Evaluation Including Preference and Forecast Confidence ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ...Overall Pattern Across the CONUS... ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Preference: General model blend (non-UKMET northern U.S.) Confidence: Slightly above average 07Z update: The 00Z UKMET appears to be too slow and more negatively tilted with the shortwave across the Great Lakes on Day 3 and is more of an outlier than its 12Z run. As such, given the good consistency and similarity with the other deterministic models, feel the UKMET should be excluded from the model preference. Elsewhere, the rest of the 00Z guidance looks reasonable and agrees well with the GFS/NAM solutions. See no reason to change the preference outside of the Great Lakes / Upper Midwest. ---previous discussion--- For the majority of the CONUS, model agreement shows a high degree of similarity on the synoptic pattern with any spread seen relatively limited through the forecast period. Therefore, a general model blend is preferred in most cases. The two areas of concern where some differences were noted lie across the Upper Midwest and Great Lakes region with the approach of a stronger shortwave trough by mid-week. The GFS remains a bit faster compared to the rest of the guidance but not significantly enough to exclude it at this time. The NAM meanwhile it is a touch more amplified, especially by Day 3 as it approaches the eastern Great Lakes region. The other region of interest is the southeast U.S. and Gulf Coast with respect to any potential tropical development as a low moving offshore. Overall, model spread is not too high but there remains higher than normal uncertainty in the eventual track and potential development. The NAM (and to some degree the GFS) are further north with the low track, keeping it right along coast through Day 3. While the non-NCEP models (12Z runs) are further south offshore. With the rest of the 00Z guidance coming in later tonight, it will be interesting to see which way the models trend. For now, a general model blend will likely be sufficient given the spread and uncertainty. Model trends at www.wpc.noaa.gov/html/model2.html 500 mb forecasts at www.wpc.noaa.gov/h5pref/h5pref.shtml Taylor