HRDPS data in GRIB2 format

The High Resolution Deterministic Prediction System or HRDPS is a set of nested limited-area model (LAM) forecast grids from the non hydrostatic version of the Global Environmental Multiscale (GEM) model with a 2.5 km horizontal grid spacing for the inner domain over one main Pan-Canadian region and a northern region over the Arctic archipelago and Greenland. The pilot model of the HRDPS is the Regional Deterministic Prediction System or RDPS (GEM Regional model). The HRDPS is operational except the northern domain which remains experimental. The fields in the HRDPS high resolution GRIB2 dataset are made available four times a day for the Pan-Canadian domain for a 48 hour forecast period (except the northern domain).

Users who will benefit most from using these new data are those for whom a detailed forecast of surface temperatures and winds is important. Especially during the change of seasons and in wintertime when rapid changes in temperature and winds cause phase transitions of precipitation (freezing rain to snow to rain for example), 2.5 km forecasts could add much value. Also in the case of short-term forecasts in the presence of complex terrain or along shores, the influence of changes in altitude, topography and nature of the terrain will be better described for phenomena at this scale (lake or sea breezes, local valley flows, phase changes, etc.). Even over less rugged terrain, or over water away from shore, these more precise forecasts could be useful, repeatedly over a long period. As well, for hydrological forecasts on smaller basins, the HRDPS should be considered.

The HRDPS not yet being equipped with its own data assimilation system, so its quality depends largely on the RDPS, which provides initial and boundary conditions, and on the global data assimilation system acting upstream. So if the forecast of the RDPS is questionable over the region of interest, it is likely that the higher resolution forecast will magnify the problems of the regional forecast. However, initial cloud and surface data are now provided by a coupled HRDPS-Caldas (Canadian Land Data Assimilation System) cycle, improving clouds, precipitation and surface fields. For forecast lead times of more than 24 hours the use of the regional or global forecasts might be required.

Available Domains

Continental

There is also a formatted gzipped ASCII file containing geographical coordinates for each grid point.

North: experimental

There is also a formatted gzipped ASCII file containing geographical coordinates for each grid point.

East

There is also a formatted gzipped ASCII file containing geographical coordinates for each grid point.

Prairies

There is also a formatted gzipped ASCII file containing geographical coordinates for each grid point.

West

There is also a formatted gzipped ASCII file containing geographical coordinates for each grid point.

Maritimes

There is also a formatted gzipped ASCII file containing geographical coordinates for each grid point.