NOAA Rapid Refresh (RAP): Hourly Weather Forecasts for North America

NOAA's Rapid Refresh (RAP) is an operational numerical weather prediction system providing frequently updated short-range forecasts. It covers North America with a 13 km horizontal resolution and 50 vertical layers, running hourly with forecast cycles integrated to 51 or 21 hours. The system uses the WRF-ARW model and GSI analysis, assimilating cloud and hydrometeor data to improve short-range cloud and precipitation forecasts.

Use Cases

• Short-term aviation weather hazard prediction based on hourly forecast cycles.
• Severe weather nowcasting and analysis based on high-frequency model updates.
• Validating and improving numerical weather prediction models based on the described 13 km resolution and 50-layer vertical structure.
• Researching cloud and precipitation processes based on the assimilation of cloud and hydrometeor data mentioned in the description.

Strengths

• Operational system run hourly, providing frequent updates for short-range forecasting.
• Covers North America with a defined 13 km horizontal resolution and 50 vertical layers.
• Uses a specific model core (WRF-ARW) and analysis system (GSI) with cloud data assimilation, as described.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count and total dataset size are unknown, which may limit suitability assessment.
• Last update date is unknown; freshness unverified.

Provenance

Source

NOAA/NCEP (National Oceanic and Atmospheric Administration / National Centers for Environmental Prediction).

Collection Method

Output from an operational numerical weather prediction model and analysis system.

Time Range

Temporal coverage is not specified in the provided metadata.

Freshness

Update frequency is hourly, but the last update date of the archived data is unknown.

Geography

North America.