jgdas_fcst ecf (v17) Analysis

jgdas_fcst.ecf (GFS v17)

Branch / tenant: dev/gfs.v17 (gw_v17) Path: ecf/scripts/gdas/forecast/jgdas_fcst.ecf Analysis date: 2026-06-11

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Summary

The GDAS deterministic forecast — runs the 9-hour coupled UFS Weather Model forecast that provides the background/first-guess for the next cycle's analysis and generates forecast output for EnKF. Uses the same shared JGLOBAL_FORECAST J-Job as GFS but with fewer nodes and shorter walltime.

Resources

Field	Value
PBS	95 nodes, 128 cpus/node = 12,160 MPI ranks, exclusive host, 1:50 wall
Modules	load_modules.sh ufswm
J-Job	JGLOBAL_FORECAST (shared GFS/GDAS/EnKF)
Exports	FCST_SEGMENT='0'

Key differences from GFS counterpart

• 95 nodes vs GFS 295 — GDAS runs same resolution but only 9 hours (vs 384).
• 1:50 walltime vs 6:00 — much shorter forecast.
• Same shared JGLOBAL_FORECAST J-Job, differentiated by RUN=gdas config.
• CRITICAL: provides first-guess for next cycle's analysis and feeds EnKF.
• GDAS forecast output also used for verification and monitoring.

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Sources

• On-disk v17: ecf/scripts/gdas/forecast/jgdas_fcst.ecf.