This section catalogues operational weather-radar networks and composites with freely downloadable gridded data. It applies the same scope filter as the rest of the repository — open data, downloadable, no paywalls or approval gates beyond simple registration — to ground-based radar remote sensing, the counterpart to the satellite observation systems.
Two distinctions shape what belongs here. First, observation, not forecast: this section documents what the radars are seeing now — reflectivity, precipitation rate, accumulation — while radar-derived nowcasts that project precipitation forward belong in the nowcasting model section. Second, data, not imagery: gridded or structured radar data (GRIB2, NetCDF, ODIM HDF5, native binary) is in scope, while rendered radar maps, web loops, and tile services are not, however widely available.
- Radar composites / mosaics — national and multi-national reflectivity and precipitation composites
- Quantitative precipitation estimation (QPE) — radar-derived rain rate and gauge-adjusted accumulations
- Single-site polarimetric data — per-radar moment and volume data (the radar counterpart to satellite Level 1)
- Both no-account access (cloud buckets, HTTP directories, THREDDS) and free-with-registration access
- Rendered radar imagery, animations, and tile/WMS viewers without downloadable gridded data (e.g. NWS RIDGE, national radar web loops, MSC GeoMet WMS)
- Radar-derived nowcast / forecast products — these project future precipitation and belong in the nowcasting model section (e.g. DWD RADVOR and RADOLAN-RV, KONRAD3D cell nowcasts)
- Non-precipitation radar — HF (ocean-surface-current) radar, wind-profiler radar, and other non-weather radar
- Object / feature detection distributed only as XML or point lists (cell tracks, mesocyclone lists) rather than gridded fields
- Real-time analyses distributed only through viewer front-ends
Radar data access is described with the same three tier labels used across the observation sections:
- Open (no account) — direct download from a cloud bucket, HTTP directory, or THREDDS server, no account or registration. This is the bulk of the section.
- Open with registration — free account or access key required, no approval gate, no commercial restriction (e.g. the Italian DPC SRI live feed; its static archive is no-account).
- Open with restrictions — free but with conditions, geographic limits, or approval requirements (none currently documented; retained for completeness).
Most operational radar data documented here is in the first tier.
| Network | Operator | Scope | Type | Format | Access | Licence |
|---|---|---|---|---|---|---|
| MRMS | NOAA / NSSL | US (CONUS + OCONUS) | Multi-sensor mosaic | GRIB2 | Open (no account) | Public domain |
| NEXRAD | NOAA / NWS · Unidata | US | Single-site (L2 / L3) | NEXRAD L2/L3 binary | Open (no account) | Public domain |
| OPERA | EUMETNET | Pan-European | Composite | ODIM HDF5 / GeoTIFF | Open (no account) | CC BY 4.0 |
| DPC SRI | DPC · FBK (Italy) | Italy | Composite | Zarr / GRIB / GeoTIFF | Open — anon archive; account for live | CC BY-SA 4.0 |
| UK Met Office SRR | Met Office | UK (international) | Composite | ODIM HDF5 | Open (no account) | CC BY-SA 4.0 |
| MET Norway | MET Norway | Nordic + Norway | Composite | NetCDF (CF) | Open (no account) | CC BY 4.0 |
| DWD | DWD | Germany | Composite + single-site | RADOLAN binary / ODIM HDF5 | Open (no account) | GeoNutzV (≈ CC BY 4.0) |
| FMI | FMI | Finland | Composite + single-site | GeoTIFF / ODIM HDF5 | Open (no account) | CC BY 4.0 |
| ČHMÚ (CZRAD) | ČHMÚ | Czechia | Composite + single-site | ODIM HDF5 | Open (no account) | CC BY 4.0 |
| HungaroMet | HungaroMet | Hungary | Composite (CMax / PseudoCAPPI / 3D) | NetCDF (zipped) | Open (no account) | CC BY-SA 4.0 |
| SHMÚ | SHMÚ | Slovakia | Composite + single-site | ODIM HDF5 | Open (no account) | CC BY 4.0 |
| KAUR | KAUR (Keskkonnaagentuur) | Estonia | Composite + single-site | ODIM HDF5 | Open (no account) | CC BY 4.0 |
| KNMI | KNMI | Netherlands | Composite + single-site | KNMI HDF5 / NetCDF | Open with account | CC BY 4.0 |
| Hochficht | GeoSphere Austria · Meteopress | Upper Austria (+ CZ / DE border) | Single-site volumes only | ODIM HDF5 | Open (no account) | CC BY 4.0 |
| MeteoSwiss | MeteoSwiss | Switzerland (+ Alpine region) | Composite + single-site | ODIM HDF5 | Open (no account) | CC BY 4.0 |
| DMI | DMI | Denmark | Composite + pseudo-CAPPI + single-site | ODIM HDF5 | Open (no account) | CC BY 4.0 |
Note the licence spread: US products are public domain (NODD); OPERA and MET Norway are CC BY 4.0; the UK and Italian composites are CC BY-SA 4.0 (ShareAlike); DWD is GeoNutzV with mandatory attribution.
For the most frictionless access, these networks distribute gridded data with no account or registration:
| Network | No-account endpoint(s) | Host / region |
|---|---|---|
| MRMS | s3://noaa-mrms-pds; https://mrms.ncep.noaa.gov/ |
AWS us-east-1 / NCEP |
| NEXRAD | s3://unidata-nexrad-level2 (+ -chunks, unidata-nexrad-level3); gs://gcp-public-data-nexrad-l2 / -l3 |
AWS us-east-1 / Google Cloud |
| OPERA | ECMWF EWC S3 (anonymous) + MeteoGate ORD API | European Weather Cloud |
| DPC SRI | ECMWF EWC S3 (anonymous); Zenodo 10.5281/zenodo.18637608 |
EWC / Zenodo |
| UK Met Office SRR | s3://met-office-radar-obs-data |
AWS eu-west-2 |
| MET Norway | https://thredds.met.no/ (OPeNDAP / HTTP / WCS / WMS) | MET Norway THREDDS |
| DWD | https://opendata.dwd.de/weather/radar/ | DWD Open Data |
| FMI | s3://fmi-opendata-radar-geotiff, s3://fmi-opendata-radar-volume-hdf5 |
AWS eu-west-1 |
| ČHMÚ (CZRAD) | https://opendata.chmi.cz/meteorology/weather/radar/ | ČHMÚ Open Data |
| HungaroMet | https://odp.met.hu/weather/radar/composite/nc/ | HungaroMet ODP |
| SHMÚ | https://opendata.shmu.sk/meteorology/weather/radar/ | SHMÚ Open Data |
| KAUR | https://avaandmed.keskkonnaportaal.ee/dhs/Active | KAIA (Keskkonnaportaal) |
| Hochficht | https://public.hub.geosphere.at/datahub/resources/radar_volumen_hochficht-v1-5min/filelisting/ | GeoSphere Data Hub (S3-compatible) |
| MeteoSwiss | https://data.geo.admin.ch/api/stac/v1/collections/ch.meteoschweiz.ogd-radar-precip (and …-radar-hail); https://api.meteogate.eu/eu-eumetnet-weather-radar/ |
FSDI data.geo.admin.ch / EUMETNET MeteoGate |
| DMI | https://opendataapi.dmi.dk/v1/radardata/ (STAC / OGC API–Features; files via /download/{file-name}) |
DMI Open Data |
The US buckets and the UK bucket take --no-sign-request; OPERA and the Italian archive use anonymous S3 on the ECMWF European Weather Cloud; MET Norway, DWD, ČHMÚ, HungaroMet, and SHMÚ are plain THREDDS / HTTPS; KAUR is the KAIA SharePoint file store (direct Content.aspx file URLs over HTTPS). MeteoSwiss is the only entry served through two unrelated open APIs — a STAC catalogue for the gridded composites (plain unsigned asset URLs) and an OGC API–EDR service for the single-site volumes, whose CoverageJSON response carries the ODIM download links. DMI is the second STAC-based entry: a single service covering all three product families, where the item response gives a file name that must be passed to a separate /download/ endpoint rather than a directly resolvable asset URL.
Entries are organized by operating country or organization, mirroring the structure used elsewhere in the repository:
observations/radar/
usa/ — MRMS (multi-sensor mosaic), NEXRAD (single-site L2/L3)
eu/ — OPERA (pan-European composite)
italy/ — DPC SRI (national composite)
uk/ — UK Met Office SRR (national / international composite)
norway/ — MET Norway (Nordic reflectivity + Norwegian accumulation)
germany/ — DWD (RADOLAN, reflectivity composites, single-site)
finland/ — FMI (composites, single-radar products, ODIM volumes)
czechia/ — ČHMÚ (CZRAD: single-site volumes + national composites)
hungary/ — HungaroMet (national composites: CMax, PseudoCAPPI, 3D)
slovakia/ — SHMÚ (CZRAD-style: single-site volumes + national composites)
estonia/ — KAUR (Harku + Sürgavere: single-site volumes, products + national composite)
netherlands/ — KNMI (national network: volumes, composites, radar/gauge QPE)
austria/ — Hochficht (single GeoSphere × Meteopress C-band radar; volumes only)
switzerland/ — MeteoSwiss (precipitation + hail composites; polar volumes via EUMETNET ODR)
denmark/ — DMI (national composite, per-radar pseudo-CAPPI, polarimetric volumes)
Each entry covers a network or composite product rather than an individual radar — MRMS as one mosaic, NEXRAD as one single-site archive — with the single exception that a national service publishing genuinely distinct products (e.g. DWD's composites and single-site sweeps) documents them together in one entry.
Several systems were evaluated but not given full entries, for reasons worth recording. This catalog's radar entries are reserved for real-time (or near-real-time) operational feeds delivered in a standard gridded binary container; genuinely open datasets that fall short only on timeliness or only on container format are noted here instead.
- Canada (ECCC / MSC) — viewer/imagery only. The open channels are rendered GIF (Datamart) and WMS map images (GeoMet); there is no open gridded feed. Worth revisiting if a WCS coverage or GRIB/GeoTIFF path appears (a "Radar product guide" is pending on the MSC side).
- MET Norway HF-radar — High-Frequency radar measuring ocean surface currents, not precipitation. A different instrument class; not weather radar.
- Rendered image services —
api.met.noradar, NWS RIDGE / RIDGE II tiles, and national WMS/viewer loops return images, not gridded data. - Radar-derived nowcasts — DWD RADVOR and RADOLAN-RV, KONRAD3D, the nowcast fields bundled inside MRMS (FLASH, ANC), and CWA Taiwan's next-1-hour radar QPF (
F-B0046, echo extrapolation on the same 441 × 561 grid as its QPE sibling) project future states; they are flagged for the nowcasting model section rather than documented here. - IDEAM (Colombia) — genuine open single-site Level II data in Sigmet/IRIS format (
s3://s3-radaresideam,us-east-1, CC BY 4.0), with a historical archive back to 2018. Noted here rather than given a full entry because the recent feed is delayed and intermittent rather than real-time: checked against the live bucket, the newest data typically runs 1–2 days behind, with whole days absent and only part of the network present on a given day. Valuable as a historical Level II archive — worth a full entry if IDEAM moves to a reliable real-time feed. - CWA (Taiwan) — open, real-time, genuinely gridded radar data, excluded on container format alone. CWA publishes a national composite reflectivity (
O-A0059— 921 × 881 at 0.0125°, dBZ, origin 115°E/18°N on TWD67, updated every 10 minutes, blending the Wufenshan, Hualien, Chigu, Kenting, Shulin, Nantun, and Linyuan radars) and a gauge-corrected past-1-hour QPE (O-B0045— 441 × 561 at 0.0125°, mm, origin 118°E/20°N), both anonymously downloadable froms3://cwaopendata/Observation/(ap-northeast-1) under the Taiwan Open Government Data License. Grid geometry, units, scan order, and missing-value codes (−99 invalid, −999 outside radar coverage or QC-removed) are all properly documented in the accompanying metadata — but the field itself arrives as comma-separated scientific-notation floats inside a JSON or XML wrapper (~8.9 MB per composite), not GRIB2, NetCDF, or ODIM HDF5. The bucket is also latest-only: each product is a fixed key overwritten in place, with no date partitioning and no archive. Worth a full entry if CWA adds a binary gridded container. - MeteoSwiss reflectivity and convection composites — the MeteoSwiss open-data documentation lists both product families but marks them "(not yet realised)"; the pages are placeholders with no data. Switzerland therefore has no open gridded reflectivity composite through its national channel — only single-site polar sweeps via EUMETNET ODR, or the OPERA pan-European composite. Worth re-checking; the placeholders imply planned releases.
Other national radar services with open real-time gridded feeds may be added as they are verified.
../satellites/README.md— the parallel observation section (spaceborne remote sensing). Radar and satellite are the two observation branches underobservations/.../../models/nowcasting_models/— radar-derived nowcasts (DWD RADVOR / RADOLAN-RV, KONRAD3D, and similar) live here rather than in this section.- NWP entries that assimilate this data — MRMS and NEXRAD reflectivity feed the US convection-allowing models (HRRR, RAP); OPERA reflectivity is assimilated by several European limited-area models (e.g. ALADIN-HR, CHMI-LAM); the MeteoSwiss radars feed ICON-CH1/2-EPS via latent heat nudging, and its hail products consume an ICON-CH1-EPS freezing-level forecast in return — the one two-way case in the catalog. The radar entries here are the observational sources those model entries reference.
Additions and corrections to radar entries follow the same conventions as the rest of the repository:
- Verify the data is genuinely free and downloadable through a permanent open channel (free registration is acceptable; paywalls and approval gates are not), and that it is a real-time or near-real-time operational feed — delayed-only or archive-only datasets are noted under "What's intentionally missing" rather than given full entries
- Confirm it is an observation, not a nowcast/forecast — radar-derived nowcasts belong in the nowcasting model section
- Confirm the data is gridded and delivered in a standard binary container (GRIB2, NetCDF, ODIM HDF5, native binary), not rendered imagery. Gridded fields serialised as delimited text inside a JSON or XML wrapper are noted under "What's intentionally missing" rather than given full entries — see CWA (Taiwan) there
- Use the radar template (
templates/radar.template.md) as a starting point - Place new entries in the appropriate
observations/radar/<country-or-region>/directory - Update this README's quick-reference tables when adding new entries
Radar data servers routinely mix observation and nowcast in a single tree — DWD is the clearest case, but MRMS bundles derived nowcast fields too. This section documents the observational products (reflectivity, precipitation rate, accumulation, single-site moments); where a feed also carries radar-derived nowcasts, the entry documents the observational part and flags the nowcast part for the nowcasting section.
Radar feeds are also comparatively volatile: buckets get renamed (NEXRAD's Level II archive moved from noaa-nexrad-level2 to unidata-nexrad-level2), access gates change (OPERA's IP whitelisting was removed in 2026), and many feeds are short rolling windows rather than deep archives — DWD and ČHMÚ retain hours to days, while DMI's 180 days and FMI's multi-year S3 buckets are the outliers in the other direction. Entries note these where known, but the live endpoint is always the authoritative source — verify against it before relying on a path.