Model Diagnostics
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Model Diagnostic Discussion

Model Verification

Model Biases

NCEP Synergy Meeting Highlights

Numerical Model Output


Model Diagnostic Discussion

The Model Diagnostic Discussion NFDPMDHMD describes performance attributes of the GFS and NAM models for the most recent 00Z or 12Z run. For more information about this discussion, including recent changes and issuance deadlines, please read the following detailed product description.

NAM and GFS Model Trend Graphics

These graphics supplement the Model Diagnostic Discussion by comparing 500-mb geopotential height and sea level pressure every 6-h from F00-F84 from the most recent 00Z or 12Z NAM and GFS model runs to output from the model initialized 12 hours and 24 hours earlier. Difference fields between the current and older runs can also be displayed.
NAM 500-mb Height
NAM Sea Level Pressure
GFS 500-mb Height
GFS Sea Level Pressure

WPC 500-mb Height Pattern Graphics

These graphics supplement the Model Diagnostic Discussion by depicting the WPC preferred 500-mb geopotential height pattern every 12 hours from F36 through F84. The 500-mb height pattern from several numerical models can also be overlain with the WPC preferred pattern for comparison. These graphics are updated after the final issuance of the PMDHMD.

500-mb Height Pattern


Model Verification

The links below allow you to ascertain how well a model forecast has verified as a function of forecast hour, cycle, and field. For some fields two map projections are provided, one over the CONUS, and a second over Alaska.

  500 MB SURFACE
NAM

00/12 UTC Cycle CONUS

00/12 UTC Cycle Alaska

06/18 UTC Cycle CONUS

06/18 UTC Cycle Alaska

00/12 UTC Cycle CONUS

00/12 UTC Cycle Alaska

06/18 UTC Cycle CONUS

06/18 UTC Cycle Alaska

ECMWF

00/12 UTC Cycle CONUS

00/12 UTC Cycle Alaska

00/12 UTC Cycle CONUS

00/12 UTC Cycle Alaska

GFS

00/12 UTC Cycle CONUS

00/12 UTC Cycle Alaska

06/18 UTC Cycle CONUS

06/18 UTC Cycle Alaska

00/12 UTC Cycle CONUS

00/12 UTC Cycle Alaska

06/18 UTC Cycle CONUS

06/18 UTC Cycle Alaska

UKMET

00/12 UTC Cycle CONUS

00/12 UTC Cycle Alaska

00/12 UTC Cycle CONUS

00/12 UTC Cycle Alaska

NCEP EMC provides performance statistics on the models at the NCEP EMC MODEL PERFORMANCE site.


Model Biases

Model bias information is provided in two ways:
  1. Subjectively (by compiling impressions from forecasters)
  2. Objectively (by automated comparison of model forecasts to model initialization)

Subjective List of Observed Model Biases

Interactive Objective Comparision of Model Biases
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NCEP Synergy Meeting Highlights

Meetings between EMC, NCO, the NCEP Operational Centers, MDL, and NWS Regions are held routinely to discuss short-term model implementation plans in concert with super computer and communication system development. Operational feedback from users is incorporated into these plans.
 
Highlights from the Latest Meeting

Archived Highlights
 

Numerical Model Output
Links to sites with model output