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CWFIS (Canadian Wildland Fire Information System — fire danger and behaviour grids)

What this model is

CWFIS is Natural Resources Canada's operational fire danger system. It produces daily national grids of the Canadian Forest Fire Danger Rating System — both the Fire Weather Index (FWI) subsystem, which measures fuel moisture and fire danger from weather alone, and the Fire Behaviour Prediction (FBP) subsystem, which adds a fuel type map to produce rate of spread, intensity and consumption quantities.

Grids are generated by the Canadian Forest Service's Spatial Fire Management System (SFMS) and served through a GeoServer instance at 2 km resolution over Canada. Unusually for this catalogue, the distribution channel is not a file tree but an OGC Web Coverage Service, which returns 32-bit float GeoTIFF and supports both spatial and temporal subsetting.

Both current-conditions analyses and forecasts are served from the same time-enabled coverages, distinguished by the requested date — see Data availability.

Who runs it

  • Organization: Canadian Forest Service, Natural Resources Canada (Northern Forestry Centre, Edmonton)
  • Country / region: Canada

What area it covers

  • Coverage: Canada and adjacent territory
  • Domain details (verified): EPSG:3978 extent −2,378,164.08 to 3,039,835.92 easting, −707,617.77 to 3,854,382.23 northing. In geographic terms the GeoServer advertises 174.28°W–11.45°W, 35.84°N–83.40°N.
  • Masked areas: non-burnable and out-of-domain cells carry the float nil value −3.4028235 × 10³⁸. A nil in a fire danger raster generally means "not burnable" rather than "missing".

Basic details

  • Model type: Deterministic fire danger and fire behaviour model
  • Core fire danger engine: Spatial Fire Management System (SFMS), Canadian Forest Service, implementing the Canadian Forest Fire Danger Rating System
  • Rating system implemented: Canadian FWI system plus the FBP subsystem
  • Forecast length (verified): 11 days — coverage time extents ran to 2026-08-21 when checked on 2026-08-10, and dated forecast layers fdr20260811xf through fdr20260821xf were present
  • Update frequency / cycles: daily
  • Valid time convention: daily fire danger, computed on the CFFDRS convention of local mid-afternoon conditions. TBD — the exact hour is not stated in the service metadata; the daily time axis carries a 00:00:00Z stamp, which is a file convention rather than the valid time of the index.

Grid and projection

  • Grid type: projected raster
  • Projection / CRS: EPSG:3978 (NAD83 / Canada Atlas Lambert) — a projected national grid, unlike most entries in this repository, which are geographic
  • Horizontal resolution (verified): 2 km, offset vectors (2000, 0) and (0, −2000)
  • Grid dimensions (verified): 2709 × 2281
  • Note — origin convention differs between coverages. The fwi and fdr coverages report a grid origin of (−2378164.081, 3854382.229); every other coverage reports (−2377164.081, 3853382.229), exactly one half-cell (1000 m) inside it. The envelopes are identical. This is a corner-versus-centre reporting difference in the service metadata, not a different grid, but it will produce a one-kilometre offset in anything that georeferences from the origin without checking.
  • Auxiliary grids on a different mesh: greenup and grasscuring are served at 1 km on a 5430 × 3639 grid with a different extent (−2,387,000 to 3,043,000 easting, −740,000 to 2,900,000 northing) and a byte data type with nil −127. Do not assume a common grid across the whole service.

Meteorological forcing

  • Driving weather source: interpolated station observations for current conditions; forecast weather for the forward days. TBD — the specific numerical weather prediction model behind the 11-day forecast is not named in the CWFIS data services documentation. The documentation names SCRIBE as the source for a companion 24-hour station-point forecast product (firewx_scribe_fcst), but does not state what drives the gridded long-term forecast layers.
  • Required inputs: the FWI codes need temperature, relative humidity, wind speed and 24-hour precipitation. All four are served as their own coverages (temp, rh, ws, precip), which makes this one of the few systems in the catalogue where the forcing fields and the derived indices are distributed side by side on an identical grid.
  • Bias correction / downscaling: TBD

Moisture code carryover and initialization

  • Carryover codes: Fine Fuel Moisture Code, Duff Moisture Code and Drought Code all persist between days. The Drought Code in particular integrates over months, so forecast-day values inherit an antecedent state computed from observed weather.
  • State source for forecast runs: the current-conditions run driven by station observations. The documentation notes for fdr_current that the layer "will show current days forecast conditions until the actual weather data is received at which point actual fire danger will be available" — so the same-day layer transitions from forecast to analysis in place during the day, which matters for reproducibility.
  • Seasonal startup / overwintering: TBD — the CWFIS background pages are JavaScript-rendered and could not be read from outside a browser
  • Greenup / curing state: yes — greenup (deciduous green-up) and grasscuring are served as separate 1 km coverages, updated daily but with no forecast extension (time extents ended 2026-08-10 while the danger coverages ran to 2026-08-21)

Fuel and static inputs

  • Fuel type map: cffdrs_fbp_fuel_types (national FBP fuel types), also served at 100 m as cffdrs_fbp_fuel_types_100m
  • Elevation: elevation_250m
  • Static layer distribution: yes — both the fuel map and the elevation grid are retrievable through the same WCS as the forecasts, so the FBP inputs are reproducible

What it provides

FWI system components (fwi, ffmc, dmc, dc, isi, bui, dsr), plus fdr (Fire Danger Rating).

FBP fire behaviour outputs (hfi head fire intensity, ros rate of spread, cfb crown fraction burned, sfc surface fuel consumption, tfc total fuel consumption, ft fire type, fmc foliar moisture content).

Weather fields (temp, rh, ws, wdir, precip).

Smoke and dispersion diagnostics (adi atmospheric dispersion index, vi ventilation index, dmix transport wind direction, umix transport wind speed, zh mixing height, stab stability).

Fuel and phenology (cffdrs_fbp_fuel_types, greenup, grasscuring, elevation_250m).

Each danger and behaviour variable exists in two forms: a time-enabled base coverage (e.g. fwi) and a _current snapshot (e.g. fwi_current).

Data availability

  • Is the data free? Yes — anonymous, no registration, no API key
  • License: Open Government Licence – Canada. Requested citation: Canadian Forest Service. Canadian Wildland Fire Information System (CWFIS), Natural Resources Canada, Canadian Forest Service, Northern Forestry Centre, Edmonton, Alberta. http://cwfis.cfs.nrcan.gc.ca. Licence text at https://cwfis.cfs.nrcan.gc.ca/downloads/licence.txt
  • Is the data downloadable? Yes
  • Output geometry: Gridded raster
  • Access mechanism: OGC Web Coverage Service (WCS 2.0.1). GetCoverage returns 32-bit float GeoTIFF, uncompressed, big-endian. Spatial subsetting via subset=E(...)&subset=N(...) in projected metres, temporal subsetting via subset=time("...").
  • Data formats: GeoTIFF via WCS. WMS on the same GeoServer additionally offers GIF, JPEG, KML, PDF and PNG — those are rendered images and out of scope.
  • Service endpoints:
    • WCS: https://cwfis.cfs.nrcan.gc.ca/geoserver/public/wcs?service=WCS&version=2.0.1&request=GetCapabilities
    • WMS: https://cwfis.cfs.nrcan.gc.ca/geoserver/public/wms?request=getcapabilities
  • Coverage naming: WCS coverage IDs are prefixed public__, e.g. public__fwi, public__fdr20260815xf. WMS layer names omit the prefix.
  • Archive and forecast depth (verified):
    • fwi and fdr: 2018-01-01 to 2026-08-21 — an eight-year archive plus the forecast horizon on a single coverage
    • all other danger, behaviour and weather coverages: 2024-01-01 to the forecast horizon
    • greenup, grasscuring: 2024-01 to the current day, no forecast
    • adi, vi, dmix: trailing the current day by two to four days
  • Datamart (separate, mostly out of scope): https://cwfis.cfs.nrcan.gc.ca/downloads/ carries station FWI observations as CSV (fwi_obs/) and agency fire danger classes as shapefiles (fire_danger/). The shapefile product is a derived cartographic classification, not the model raster, and is out of scope.

Two ways to reach the forecast, and the second is better. The service exposes forecasts both as dated layers following the pattern <var><YYYYMMDD>xf — present only for fdr and hfi — and through the time dimension on the base coverages, which is available for the full variable set. Live-verified 2026-08-11: GetCoverage on public__fwi with subset=time("2026-08-18T00:00:00.000Z") returned valid float data distinct from both the current day and an archive slice (a 50 × 50 test window gave means of 0.54 for 2020-07-15, 5.15 for 2026-08-11, 8.51 for 2026-08-18 and 10.26 for 2026-08-21). The dated-layer naming therefore understates what is available — every FWI component and FBP output is retrievable as a forecast, not just fire danger rating and head fire intensity.

One syntax caveat: the quotes in the time subset must be percent-encoded (%22). A literal subset=time("...") returns HTTP 400.

Verification status. Grid dimensions, resolution, projection, extent, nil values, data type, time extents, and both forecast access routes were verified live against the WCS GetCapabilities, DescribeCoverage and GetCoverage endpoints on 2026-08-10/11, including decoding returned GeoTIFFs. The meteorological forcing model, the valid-time hour, and the danger class breakpoints remain documentation gaps.

Notes

  • WMS and WCS expose different things, and only WCS is in scope. This distinction is load-bearing for this category: the same GeoServer serves rendered images over WMS and the underlying rasters over WCS, and a layer's presence on one does not guarantee it on the other. For contrast, the European EFFIS service advertises comparable fire danger layers over WMS but returns an error on WCS GetCapabilities, because its rasters are tile-indexed without WCS virtual dataset metadata — which is why the operational European GEFF forecast is excluded from this catalogue while CWFIS is included.

  • Documentation is behind the service. The CWFIS data services PDF gives a worked example using fwi20230614xf, implying dated forecast layers for the Fire Weather Index. No such dated layer exists today — only fdr and hfi carry the xf naming. The FWI forecast is still available, but through the time dimension rather than through the dated layer the documentation points at. Follow the capabilities document, not the PDF.

  • The same-day layer is not stable. fdr_current shows forecast conditions until observed weather arrives, then switches to the analysed value in place. A same-day retrieval is not reproducible unless the retrieval time is recorded alongside it.

  • Two grids in one service. The danger, behaviour and weather coverages share a 2 km EPSG:3978 grid; greenup and grasscuring are on a separate 1 km grid with a different extent and a byte data type. Any pipeline treating the service as homogeneous will break on the phenology layers.

  • Index scaling. The FWI components are unbounded and open-ended, and the danger class breakpoints that turn fwi into fdr are agency-specific rather than intrinsic to the index. TBD — the breakpoints are not published in the service metadata; the GeoServer styles (cffdrs_fwi_cbf, cffdrs_fdr) encode them and could be read from the SLD.

  • Relationship to other models. The seasonal counterpart in this catalogue, which also implements the Canadian FWI system among others, is CEMS Fire Seasonal — but note that runs GEFF at global scale from SEAS5, with no fuel map and therefore no fire behaviour outputs, so the two are complementary rather than comparable. Smoke dispersion models are filed under air_quality_models/, not here; the dispersion diagnostics served by CWFIS (adi, vi, mixing height) are fire-weather indices, not transport model output.

  • AI relationship. None identified.

Official documentation

Key references

  • Van Wagner, C.E. (1987). Development and structure of the Canadian Forest Fire Weather Index System. Forestry Technical Report 35, Canadian Forestry Service.
  • Forestry Canada Fire Danger Group (1992). Development and structure of the Canadian Forest Fire Behavior Prediction System. Information Report ST-X-3.