CPC proposes moving UVI forecasts 3 hours later as GCAFS replaces GEFS aerosols
CPC is proposing to move UVI forecast delivery from 1830Z to 2130Z because GCAFS aerosol guidance would arrive 3 hours later than the current GEFS aerosol inputs.
GribStream Blog
Updates on data feeds, model launches, and product releases.
NBM v5.0 goes live April 15, 2026: what to check before cutover
NWS has set April 15, 2026 for NBM v5.0, with longer hourly guidance, upgraded QPF and snow products, and a clear cutover date for validation.
GEFS v12.3.18 fixes missing wave-station ensemble stats on NOMADS
NWS says GEFS v12.3.18 restores missing spread and probability ensemble statistics in the NOMADS wave-station products, with the fix effective on or about February 24, 2026.
ECMWF sets May 12, 2026 for IFS Cycle 50r1 and AIFS v2
ECMWF has scheduled IFS Cycle 50r1, AIFS Single v2, and AIFS ENS v2 for May 12, 2026, with same-day model changes and a few concrete stream and level updates to check.
NBM v5 parallel datasets now available
GribStream now exposes NOAA's experimental NBM v5 parallel datasets with hourly guidance through 48 hours, QM QPF/PoP, upgraded snow and wind products, and new fire-weather fields.
NOAA NAM datasets now available
GribStream now supports NOAA NAM awphys, awip12, conusnest.hiresf, and goes218 for CONUS, with history back to September 16, 2021.
NOAA CDAS to CORe in March 2026: what GribStream users should expect
NOAA is replacing CDAS with CORe on March 18, 2026. CORe remains public GRIB2, and if NOAA publishes an AWS mirror, GribStream expects to support it quickly.
ECMWF IFS Cycle 50r2: full GRIB2 transition and what to test now
ECMWF says IFS Cycle 50r2 will move all parameters to GRIB2. Here is the latest timeline, migration details, and practical checks for weather-data pipelines.
GDAS global analysis fields now available
GribStream now supports NOAA GDAS (Global Data Assimilation System): global analysis-first fields on a 0.25 deg grid with 0-9 hour lead times.
CDAS1 climate assimilation fields now available
GribStream now supports NOAA CDAS1 (Climate Data Assimilation System): global climate-oriented assimilation fields on a 1.0 deg grid with 0-9 hour lead times.
NBM OCONUS core grids now available: Alaska, Hawaii, Puerto Rico, Guam, and Oceanic
GribStream expanded NOAA's National Blend of Models (NBM) beyond CONUS with core grids for Alaska, Hawaii, Puerto Rico, Guam, plus the Oceanic domain.
RTMA Rapid Update (15-minute) CONUS actuals now available
GribStream added NOAA RTMA Rapid Update (rtma2p5_ru): 15-minute near-real-time surface analyses on the 2.5 km CONUS NDFD grid.
HRRR sub-hourly (15-minute) surface fields now available
GribStream added NOAA HRRR sub-hourly surface output (wrfsubhf) with 15-minute valid times out to 18 hours for intraday workflows.
NOAA tests GTGN: a 15-minute turbulence nowcast built on HRRR and observations
NOAA's Aviation Weather Center is seeking feedback on experimental GTGN, a 15-minute turbulence nowcast that blends GTG short-term forecasts with PIREPs, EDR reports, radar-derived signals, lightning, and METAR data over the HRRR CONUS domain.
NOAA proposes replacing GEFS aerosol products with GCAFS v1.0
NOAA/NCEP is soliciting comments on replacing GEFS v12 aerosol products with the Global Chemistry and Aerosol Forecast System (GCAFS) v1.0, including new cadence, new analyses (GCDAS), and updated aerosol modeling and assimilation.
NOAA makes the AI GFS family operational (AIGFS, AIGEFS, HGEFS)
NCEP announced operational rollout of AIGFS, AIGEFS, and HGEFS effective Dec 17, 2025 (12Z), delivering GraphCast-based deterministic and ensemble forecasts on NOMADS.
ECMWF IFS Cycle 50r1 upgrade targets early 2026 operations
ECMWF Newsletter 185 details IFS Cycle 50r1, a coupled ocean and sea-ice upgrade with NEMO4-SI3, assimilation changes, and major compute savings, planned for early 2026 operations.
ECMWF opens the full Real-time Catalogue to all users
ECMWF made its entire Real-time Catalogue openly available under CC BY 4.0 starting Oct 1, 2025, expanding access beyond the previous free subset.
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.
NBM fix restores tropical 10 m wind grids when NHC data are missing
NWS updated NBM tropical wind processing so missing NHC 10 m wind grids are replaced with deterministic 10 m wind fields, starting Sept 2, 2025 at 13Z.
RTMA v2.10.10 minor upgrade adds FAA station KJKA
NWS updated RTMA to v2.10.10 on Aug 26, 2025 (18Z) to add FAA station KJKA to the station list.
LAMP/GLMP v2.7 upgrade adds new flight-category guidance and visibility updates
NWS announced LAMP/GLMP v2.7 effective Sep 16, 2025, adding new flight-category bulletins, updated visibility thresholds, new station guidance, and an Alaska ceiling fix, with an Oct 9 update.
NBM percentile thinning proposed for Spring 2026
NWS proposes reducing NBM percentile output to 5th-95th (step of 5) plus min/max, to manage data volume as the blend adds new probabilistic fields.
ECMWF AIFS operational and ensemble now on GribStream
AIFS operational and ensemble datasets are live, providing AI-based global forecasts with both deterministic and probabilistic outputs.
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.
GEFS aerosol 06/18Z cycle discontinuation proposed for 2026
NWS proposes ending the 06Z/18Z GEFS aerosol component forecasts by April 1, 2026, while keeping the 00Z/12Z aerosol cycles and all non-aerosol GEFS members unchanged.
RRFS and RRFS Ensemble now supported
GribStream now serves NOAA's RRFS deterministic and 5-member ensemble datasets at convection-allowing resolution.
NBM v5.0 proposed for April 2026: major QPF, snow, and AI-input changes
NWS is soliciting comments on a proposed NBM v5.0 upgrade with new QM QPF/PoP, expanded snow products, higher-resolution inputs, and ECMWF AI/IFS input.
ECMWF takes AIFS-ENS operational (ensemble AI forecasts)
ECMWF moved AIFS-ENS into operations on July 1, 2025, running a 51-member AI ensemble alongside the physics-based IFS ensemble.
RRFS proposed to replace NAM, HiresW, HREF, and NARRE in early 2026
NWS proposes retiring several legacy regional models in favor of the Rapid Refresh Forecast System (RRFS) and REFS, with a comment period through July 26, 2025.
Full GEFS ensemble members now available
GribStream now serves all GEFS ensemble members, not just the mean, enabling true probabilistic workflows.
ECMWF IFS ensemble and wave ensemble now available
IFS Enfo and IFS Waef are now on GribStream, providing 51-member ensembles for atmosphere and wave guidance.
ECMWF IFS deterministic wave model now available
GribStream now serves ECMWF IFS Wave deterministic forecasts for global ocean wave conditions.
ECMWF IFS operational now available
GribStream now serves ECMWF IFS Operational (HRES) with 0.25 deg global output and 15-day horizons.
Query forecasts like a database
GribStream expanded into a searchable weather archive with expressions, time-travel queries, and richer demos.
Quickstart guide: expressions, filters, and time-travel queries
A practical quickstart guide now covers tokens, response formats, named locations, time-travel, and expressions.
How to access the GribStream API
A quick FAQ on where to access the API, create a token, and start making requests.
HRRR corn growth simulation demo (PTU + stress modeling)
A new HRRR-driven demo simulates corn growth using PTU, ET0, and stress factors, powered by expression-based queries.
NBM v4.3 upgrade goes live May 20, 2025
NWS announced NBM v4.3 with improved tropical cyclone wind feature-matching and updated SPC probabilistic severe products, effective May 20, 2025 at 12Z.
NBM snow accumulation demo for ski resorts
An NBM-based demo tracks snow and precipitation at ski resorts across North America.
Browse and compare NOAA model data with the demo dashboard
A new embedded dashboard lets you query the API directly, compare models, and explore parameters interactively.
URMA Great Lakes change: GLERL pseudo-observations disabled in obsproc v1.2.3
NOAA/NCEP disabled GLERL pseudo-observations in URMA over the Great Lakes as part of an obsproc v1.2.3 upgrade, citing low wind-speed bias impacting NBM guidance. Effective on or about March 24, 2025.
NOAA CFS models now available on GribStream
GribStream now supports the Climate Forecast System (CFS) with PGBF, FLXF, OCNF, and IPVF products back to 2018.
GEFS Chem, Wave Prob, and Atmos Mean now available
GribStream added GEFS Chem, GEFS Wave Prob, and GEFS Atmos Mean datasets for air quality, wave risk, and mean guidance.
Pricing update: Pro plans now include double the quota
GribStream doubled Pro plan quota while keeping prices steady and reduced coordinate bundle sizes for smaller requests.
Query sparse times with timesList
The API now supports timesList so you can request specific timestamps without pulling entire hourly ranges.
HRRR model now available
GribStream added NOAA's HRRR with 3 km resolution, hourly updates, and history back to 2014.
OpenAPI spec and Swagger UI now available
GribStream now provides an OpenAPI spec and Swagger UI so you can generate clients and explore endpoints quickly.
RAP model support and Skew-T examples
GribStream added NOAA RAP support and published a Python Skew-T log-P example.
GribStream: historical weather forecast API
A short overview of GribStream as a SaaS API for historical weather forecasts.
Product ideas and feedback thread
An open thread inviting ideas and feedback on future GribStream features.
Launching on Product Hunt
GribStream launched on Product Hunt and shared the announcement with the community.
API documentation published
GribStream documentation is now live for getting started and exploring endpoints.
GFS model now available
GribStream added the Global Forecast System (GFS) with historical forecasts and a demo viewer.
Introducing GribStream
Introducing GribStream: a fast API for historical weather forecasts with time-travel support and bulk extraction.