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Model Diagnostics Discussion
(Caution: Version displayed is not the latest version. - Issued 0652Z Jul 15, 2018)
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Abbreviations and acronyms used in this product
Geographic Boundaries -  Map 1: Color  Black/White       Map 2: Color  Black/White

Model Diagnostic Discussion
NWS Weather Prediction Center College Park MD
252 AM EDT Sun Jul 15 2018

Valid Jul 15/0000 UTC thru Jul 18/1200 UTC

...See NOUS42 KWNO (ADMNFD) for the status of the upper air

00Z Model Evaluation...with Final Preferences and Confidence

...Overall Model Analysis for the CONUS...

Overall Preference: General model blend;
                    Greatest weight on 00Z GFS, 00Z ECMWF
General Confidence: Slightly above average

---06Z UPDATE---
No change to the preliminary preferences or reasoning.

Spaghetti plot analysis shows that the height forecasts aloft from
all the deterministic models are contained well within the spread
from NAEFS and ECMWF ensemble members. Thus, all of these models
seem like plausible scenarios. Although there are some differences
from model-to-model, particularly with the two troughs (Northeast;
and West Coast to the Northern Plains), there is no consistent
bias such that any deterministic model was discounted. The 12Z
UKMET tends to show a stronger ridge in the Southwest with higher
heights on the periphery through the northern CONUS, so less
weight was placed on that model. The greatest weight was placed on
the 00Z GFS and 12Z ECMWF which are very close to the ensemble

Model trends at
500 mb forecasts at