GribStream Blog
URMA and RTMA now available: hourly actuals alongside forecasts
GribStream now serves URMA and RTMA so you can use near-real-time and verified hourly analyses next to your forecasts.
On September 6, 2025, we added URMA and RTMA to GribStream so you can pull hourly "actuals" right next to your forecasts without extra data plumbing.
URMA vs RTMA
- RTMA is the near-real-time hourly analysis (about 30-45 minutes after valid time). It is ideal for live dashboards and current conditions.
- URMA reruns RTMA with more observations and QC (about 6 hours latency). It is commonly used as analysis of record for verification and model scoring.
A practical workflow is forecast -> RTMA now -> URMA later, which keeps your products real-time while still enabling accurate backtesting and bias correction.
Why it matters
Having RTMA and URMA in the same API as NBM, HRRR, and GFS simplifies:
- Verification and skill scoring with a consistent data pipeline.
- Bias correction using the analysis-of-record.
- ML training labels with high-quality hourly truth.