Skip to main content
U.S. flag

An official website of the United States government

National Digital Guidance Database (NDGD)

The National Digital Guidance Database (NDGD) is a companion to the National Digital Forecast Database (NDFD), and provides access to computer generated forecasts that National Weather Service (NWS) forecasters use to create the official forecasts published in the NDFD. The Real-Time Mesoscale Analysis (RTMA) supports NDFD operations and provides analyses to NWS field forecasters. Many NDGD products are experimental, and none of them are official NWS forecasts.

Access Methods

NCEI provides access to many NDGD products. Data that are not available online can be ordered through the NCEI Archive Information Request System (AIRS). AIRS requests are limited to one day at a time because of the processing requirements needed to retrieve large datasets.

NCEP RTMA Documentation



NGDG Data Products
Period of Record Model Cycle Output Timestep Data Access Links
Approx. ten years to present online Daily, various cycles Various
30May2007–Present Daily, various cycles Various HAS