NCEP Global Ensemble Forecast System (GEFS) is run at T574 (about 34km horizontal resolution) with 64 levels to 192 hours, and T382 (about 52km horizontal resolution) with 64 levels from 192-384 hrs four times per day (00, 06, 12, and 18Z) on the IBM-SP computer. Data is interpolated to 1°x1° resolution out to 384 hours. All runs are shown out to 360 hrs at 6-hour intervals
For more information on the GEFS, see the GEFS home page at this location.