NCEP Modeling Synergy Meeting Highlights: July 30, 2007

 

This meeting was led my Michael Brennan and attended by Bill Bua, Keith Brill, Ed Danaher, Brent Gordon, Mark Iredell, Mary Hart, and Eric Rogers.  UCAR/COMET’s Stephen Jascourt and AFWA’s Maj. Tim Nobis attended by remote conference. 

 

1. CCS

 

Brent Gordon of NCO briefed the group of the status of several upcoming NCO implementations planned for the rest of FY07.  A detailed list of upcoming NCEP model upgrades and implementations can be found here. 

 

NCO received code to run the real time mesoscale analysis (RTMA) over Alaska from EMC this week.  The Alaska RTMA will be run in parallel for a couple of weeks and is scheduled for an implementation on 25 September. 

 

The modified configuration of the Hi-Res window WRF runs have begun a 30-day subjective evaluation period.  Changes include in increase in horizontal grid spacing to 4 km in the NMM and 5.1 km in the ARW.  Also, the domain configuration will be changed to cover the CONUS with two domains instead of three, and upgrading the WRF-NMM and WRF-ARW to the latest versions of the model.  The eastern CONUS domain will be run twice daily, while the western CONUS and Alaska domains will each be run once daily.  Operational implementation is scheduled for 11 September.

 

The new unified post-processor for the GFS is in the subjective evaluation period. This new post-processing affects derived quantities, particularly precipitation type, vorticity and vertical velocity. The Master grid is also being changed from a 0.5° lat/lon grid to a 0.3° Gaussian grid, therefore AWIPS grids created from the GFS output will be generated from the Gaussian grid.  Operational implementation is scheduled for 25 September. 

 

A multiscale wave model, using two-way grid nesting, is scheduled to be implemented on 18 September, replacing the three regional wave models currently being run for the Western Atlantic (including the Gulf of Mexico), the Eastern Pacific, and Alaska.  Eventually this model will replace the global wave model as well.

 

For the SREF, code was received in the last couple of weeks to add bias corrected output and increase the coverage over Alaska.  Real time data will be available for evaluation by the latter half of August, and operational implementation is scheduled for 9 October. Initially, both bias-corrected and raw uncorrected SREF grids will remain available.

 

The NAM physics upgrade initially scheduled for 11 September 2007 has been pulled back. EMC will continue to work on code and an implementation is tentatively scheduled for the 2nd quarter of FY08.  EMC is also testing modification to the NAM post, including the output of simulated GOES brightness temperatures.  These data are being run in parallel and are available on the web only.

 

Production is running well, except for intermittent problems with scripting and model code for the HWRF.

 

2. NOTES FROM EMC

 

2a. Global Climate and Weather Modeling Branch

 

Mark Iredell noted that there have been some problems with the computation of vertical velocity at some levels in the new unified GFS post.  All other fields look good so far, and they are awaiting feedback from the subjective evaluation period.

 

A minor data assimilation upgrade for the GSI is scheduled for the 1st quarter of FY08 to accommodate some data format changes.  Also, this upgrade will result in a fully-reproducible GSI.

 

A CFS upgrade is scheduled for the 1st quarter of FY08.  This upgrade will use 1-day old initial conditions instead of 7-day old initial conditions for the model run.  The upgrade will also add two T126 members to the CFS running out to 60 days to provide more detailed guidance to CPC for their one-month outlooks.

 

Testing is underway on a major GFS upgrade planned beyond the 1st quarter of FY08, including potential physics upgrades to the GFS.

 

2b. Mesoscale Modeling Branch

 

Eric Rogers noted that the pullback of the planned NAM upgrade was due to performance issues that arose in the last two months after the implementation of the strong balance constraint in the initial analysis.  

 

Future NAM upgrades plan to include an expanded domain to better serve Alaska and Puerto Rico, and potential physics changes including addition of gravity wave drag and the including momentum mixing in the BMJ cumulus parameterization scheme. 

 

Upcoming analysis changes for the NAM will include an upgrade to the newest version of the GSI and the assimilation of new satellite data including AIRS and QuikSCAT, perhaps by the 2nd quarter of FY08.

 

 

2c. Global Ensemble Prediction System

 

Testing is underway on a major GEFS upgrade planned beyond the 1st quarter of FY08, including testing the use of real time re-forecasting to perform improved bias correction. 

 

2d. Short Range Ensemble Forecast System

 

The SREF upgrade schedule for 9 October 2007 will decrease the grid spacing of all members to 35 km.  The planned move to all WRF components in the SREF has been postponed.

 

2e. Marine Modeling and Analysis Branch (MMAB):

 

No representative present.

 

3. Feedback from operational centers

 

None.

 

4. The next synergy meeting will be held Monday, 27 August 2007, at noon in EMC Room 209, with remote conference capability.