The Environmental Modeling Center of National Centers for Environmental Prediction (NCEP/EMC) announces the release of the high temporal frequency (twice daily) output data from the NCEP Climate Forecast System (CFS) retrospective forecasts.

A description of the CFS is given in the following (revised) article.  We recommend reference of this article when using the data.

The NCEP Climate Forecast System, 2005 : S. Saha, S. Nadiga, C. Thiaw, J. Wang, W. Wang, Q. Zhang, H. M. van den Dool, H.-L. Pan, S. Moorthi, D. Behringer, D.Stokes, M. Peña, S. Lord, G. White, W. Ebisuzaki, P. Peng, P. Xie.  (In review process by the Journal of Climate.)

Due to the considerable volume of data involved, only 8 commonly used variables are being released now. These variables are:

1. Temperature at 2-meter above ground (tmp2m)
2. Precipitation Rate (prate)
3. Zonal wind at 200 hPa  (wnd200)
4. Meridional wind at 200 hPa (wnd200)
5. Surface pressure (ps)
6. Precipitable Water (pwat)
7. Geopotential at 500 hPa (z500)

8. Geopotential at 850 hPa (z850)

You can find the data and documentation at the CFS FTP public server: http://cfs.ncep.noaa.gov

*** FUTURE RELEASE OF MORE CFS DATA ****

1. Twice-daily output data of 19 additional variables, which have been archived.

2. Monthly means of 10 oceanic variables from the CFS retrospective forecasts, i.e. depth of the 2.5, 5, 10, 15, 20, 25 and 28C isotherms, depth of the ocean mixed-layer, depth of the ocean isothermal layer, and the ocean heat content.

3. Monthly mean, and some daily, data from the 4 CMIP runs (33 year, fully-coupled free runs) of the CFS as described in :

   Wang, W., S. Saha, H.-L. Pan, S. Nadiga, and G. White, 2005: Simulation of ENSO in the new NCEP Coupled Forecast System Model. Mon. Wea. Rev, 133, 1574-1593.

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WARNING

PLEASE BE ADVISED THAT THE TWICE DAILY OUTPUT DATASETS DESCRIBED BELOW ARE NOT CHECKED FOR TECHNICAL QUALITY. USERS MAY WANT TO PERFORM SOME QUALITY CONTROL ON THE DATA BEFORE USE, OR ELSE USE THEM AT THEIR OWN RISK. PLEASE LET US KNOW IF YOU FIND PROBLEMS IN THE TECHNICAL QUALITY OF THE DATA.

RECOMMENDATION

THIS DATA IS NOT CALIBRATED. IT IS STRONGLY RECOMMENDED THAT USERS PERFORM SOME CALIBRATION ON THE FORECAST DATA BEFORE USING IT IN A PREDICTIVE ENVIRONMENT.

ATTENTION

ALL INTERNAL NCEP/IBM USERS: You can access all the data mentioned above directly from the IBM HPSS mass store system at: /hpssuser/para/climpara/daily

Selected variables are available online at: /emc4.1/climpara/daily

Please look for an announcement by us, when the additional data is released.