GribStream Blog
SREF termination proposal: NOAA suggests GEFS as the replacement
NWS seeks comments on retiring the Short Range Ensemble Forecast System (SREF) and recommends GEFS as the replacement as it transitions to UFS-supported cores.
On July 25, 2025, NOAA/NWS issued a proposal to terminate the Short Range Ensemble Forecast System (SREF), with public comments requested through August 24, 2025. The notice explains that SREF relies on legacy WRF-ARW and WRF-NMM dynamic cores and is nearing end-of-life as NCEP transitions to UFS-supported systems.
What is changing
- SREF would be retired across all distribution channels.
- All SREF data would be removed when the system is discontinued.
- NWS recommends using GEFS as the replacement ensemble for users who rely on SREF.
Why it matters
SREF has long been used for short-range ensemble guidance. Its retirement consolidates ensemble workflows around GEFS and newer UFS-aligned systems. If you depend on SREF-derived probabilistic guidance or post-processing, plan ahead to migrate and re-baseline your thresholds.
What this means for GribStream users
GribStream already supports GEFS Atmosphere, including full ensemble members. As NOAA finalizes the transition and any new feeds are made available via the AWS Open Data program, we'll keep coverage aligned with the operational ensemble guidance.
Sources
- NWS Public Information Statement 25-51 (Jul 25, 2025): https://www.weather.gov/media/notification/pdf_2025/pns25-51_soliciting_comments_sref_termination.pdf