This page documents access to ECMWF IFS and the AIFS free and open data. For licence and attribution terms, see the open datasets page. To host our open data, contact us through the support portal.

New from 20 October 2026: a finer 0.1° resolution alongside the existing 0.25°, a surface/pressure-level split, additional parameters, and a per-parameter bits-per-value reduction. The 0.1° data is published 2 hours after the 0.25° data. See What's new at 0.1° and Bits per value.

What's available

Real-time open data is published at 0.25° and 0.1° on a global grid, in GRIB edition 2 (tropical-cyclone tracks are in BUFR edition 4). The IFS streams below apply to both resolutions, the AIFS streams (AIFS Single and AIFS ENS) are published at 0.25° only. For how the 0.1° tier differs, see What's new at 0.1°.

Naming key, older names and what they are now

Old name	Stream, type	What it is
HRES	`stream=oper`	IFS Medium-range Control Forecast
HRES-WAM	`stream=wave`	IFS Medium-range Control Forecast
ENS	`stream=enfo`	IFS Medium-range Ensemble Forecast
ENS-WAM	`stream=waef`	IFS Medium-range Ensemble Forecast

Stream	Type	Model	What it is	Run times (UTC)	Steps	Format
`oper`	`fc`	IFS	IFS Medium-range Control Forecast, atmospheric — formerly HRES	00, 06, 12, 18	00/12: 0–144h by 3h, 150–360h by 6h · 06/18: 0–90h by 3h	GRIB2
`oper`	`tf`	IFS	Tropical-cyclone tracks (only when cyclones are active)	00, 06, 12, 18	00/12: 360h · 06/18: 144h	BUFR
`wave`	`fc`	IFS	IFS Medium-range Control Forecast — formerly HRES-WAM	00, 06, 12, 18	00/12: 0–144h by 3h, 150–360h by 6h · 06/18: 0–90h by 3h	GRIB2
`enfo`	`ef`	IFS	IFS Medium-range Ensemble Forecast , atmospheric — 50 perturbed members	00, 06, 12, 18	00/12: 0–144h by 3h, 150–360h by 6h · 06/18: 0–144h by 3h	GRIB2
`enfo`	`ep`	IFS	Ensemble probability products	00, 06, 12, 18	0–144h by 3h, 150–360h by 6h (file step 240 or 360 — see tip)	GRIB2
`enfo`	`tf`	IFS	Ensemble tropical-cyclone tracks (only when cyclones are active)	00, 06, 12, 18	00/12: 360h · 06/18: 144h	BUFR
`waef`	`ef`	IFS	Wave ensemble forecast — 50 perturbed members	00, 06, 12, 18	00/12: 0–144h by 3h, 150–360h by 6h · 06/18: 0–144h by 3h	GRIB2
`waef`	`ep`	IFS	Wave ensemble probability products (00 and 12 only)	00, 12	0–144h by 3h, 150–360h by 6h (file step 240 or 360)	GRIB2
`oper`	`fc`	AIFS Single (0.25° only)	Deterministic machine-learning forecast (`model=aifs-single`)	00, 06, 12, 18	6-hourly to 360h	GRIB2
`enfo`	`pf`	AIFS ENS (0.25° only)	Ensemble machine-learning forecast (`model=aifs-ens`)	00, 06, 12, 18	6-hourly to 360h	GRIB2

Probability steps (ep): use step=240 in the file name for forecast steps up to 240h, and step=360 for steps 246–360h.

Where to get it

From ECMWF

The data portal at data.ecmwf.int/forecasts is the primary source. You can browse the list of files directly.

Cloud mirrors (for scale and reliability)

The open data is replicated across the major clouds. Use these if the portal is busy or if you already work in that cloud.

Provider	Location	Notes
Amazon AWS	registry.opendata.aws/ecmwf-forecasts
Microsoft Azure	planetarycomputer.microsoft.com	Access needs a short-lived SAS token
Google Cloud	Google Cloud Marketplace

Third-party services

These re-serve ECMWF open data through their own APIs (not covered by the ecmwf-opendata Python package).

Service	Location
Open-Meteo	open-meteo.com/en/docs/ecmwf-api
Oikolab	docs.oikolab.com
TerraQuanta	openet.terraqt.com

In this section

Getting the data — the Python package, browsing, and wget/curl including single-field downloads.
File naming and formats — GRIB2/BUFR, the naming convention, index files, and MARS-vs-file-name differences.
AIFS machine-learning data — the AIFS Single and AIFS ENS open data.
Bits per value — why precision is set per parameter, with the full per-parameter table.
What's new at 0.1° — how the 0.1° tier differs, the surface/pressure split, and the ~2-hour latency.
IFS Cycle 50r1 changes — what changed in May 2026 and what it means for existing workflows.

Contents of this page

Useful Links

ECMWF Service Status

ECMWF Real-time Catalogue

ECMWF Archive Catalogue

ECMWF Open Charts

Service Information

To ensure the stability of our systems and to preserve resources for our operational activities (network, compute, etc.), access to the open-data portal is limited to between 500 to 2000 simultaneous connections.
This limit helps us guarantee reliable service for our operational users, especially during periods of high demand.

For added reliability, the open data is replicated across AWS, Azure, and Google Cloud. If you experience difficulties accessing the portal directly, you can also retrieve the data from these cloud platforms.

Get help

Support level for these datasets

Both datasets are provided as a 'self-serve' dataset - documentation is provided, but no support service.

However, if the data seems broken or corrupt, please report it via our support portal and we will respond during normal office hours.

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ECMWF Forum — search past answers, ask the community
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ECMWF open data: real-time forecasts from IFS and AIFS