Forecast Mode¶

Warning

The hands-on in this section is intended for internal BMKG users. Non-BMKG users may still be able to follow the tutorial without access to the computational resources.

Info

Please contact the team for further information at produksi.maritim@bmkg.go.id.

The operational InaCAWO forecast system runs automatically on the BMKG HPC under account cawofcst_prod, managed by ROME. This page describes how the forecast mode works; for hands-on hindcast exercises see Hindcast Mode.

Forecast schedule¶

InaCAWO produces four forecast cycles per day:

Cycle (UTC)	Forecast length	Atmospheric IC/BC	Output products
00, 12	10 days (240 h)	ECMWF-IFS (primary), GFS (backup)	FULL + ESSENTIAL
06, 18	90 hours	GFS only	FULL only

End-to-end workflow¶

flowchart TD
    A[Download global model data] --> B[Pre-process IC/BC]
    B --> C[72-hour ROMS/SWAN spin-up]
    C --> D[6-hour coupled analysis cycle]
    D --> E[Launch forecast run]
    E --> F[Post-process and disseminate]

1. Data ingest and pre-processing¶

Global model data are downloaded and converted into model-ready files:

WRF — ECMWF-IFS or GFS atmospheric IC/BC via WPS (ungrib, metgrid, real)
ROMS — CMEMS Mercator or HYCOM ocean IC/BC via MATLAB interpolation to the 70-layer grid
SWAN — ECMWF-Wave or GFSWAVE boundary conditions via MATLAB

See Configurations for data source details.

2. Spin-up and analysis cycling¶

Before each forecast, the system runs:

Standalone spin-up (72 h) — ROMS and SWAN are driven with GFS analysis forcing to produce balanced hot-start files
Coupled analysis cycle (6 h) — the full 3-way coupled model runs from T−6 to T0, producing final ocean and wave initial conditions

3. Forecast execution¶

The coupled COAWST model runs in time chunks to minimize wall-clock delay:

10-day runs (00/12 UTC): 0–24, 24–48, 48–96, 96–144, 144–192, 192–240 h

90-hour runs (06/18 UTC): shorter chunked sequence

Each chunk waits for its IC/BC data, with ECMWF preferred and GFS as automatic fallback.

4. Post-processing and delivery¶

As forecast output timesteps become available:

WRF and ROMS/SWAN outputs are converted to CF-1.8 NetCDF (FULL and ESSENTIAL)
Products are FTP-delivered to downstream systems
Plot scripts generate graphical products for the internal monitoring website

See Dissemination for output variable lists and file naming.

Key differences from hindcast mode¶

Aspect	Forecast (operational)	Hindcast
Trigger	Automatic via ROME crontab	Manual execution
Input data	Near-real-time global models	Pre-acquired reanalysis (ERA5, GLORYS12V1)
ROMS OBCs	Zero-gradient velocities	Radiation + nudging with climatology
Time pressure	Must complete within service window	No real-time constraint
Workflow	ROME job tree with backups	Simplified independent components

Accounts and access¶

Account	Node	Use
`cawofcst_prod`	`mdclogin0`	Production — do not modify without authorization
`cawofcst_dev`	`mdclogin1`	R&D testing and script development

Software deployment repositories are available at https://mms.bmkg.go.id/gitlab/mms/inacawo-deployment/.

Monitoring a forecast cycle¶

To check the status of a running or recent cycle:

# Set cycle (example: 12 UTC on 2024-05-30)
export CYCLE=2024053012

# Check cycle log directory
ls $RT_LOGS/cycles/$CYCLE/

# Check for flagged errors
ls $RT_LOGS/cycles/$CYCLE/verify/

# Review cron launch logs
ls $RT_LOGSCRON/ | grep $(date -u +%Y%m%d)

For detailed job listings and error recovery procedures, see Production and Troubleshooting.

References¶

OM_InaCAWO_Software-Manual.pdf — forecast job architecture (Jobs CF1, CF2)
Local Training InaCAWO August 2023.pdf — operational training materials
20230615_InaCAWO_SAT_Operation_Test_M1_623_v1.0.pdf — operational acceptance criteria