ToM > MSC data > RDPS > Storm tracks from the RDPS on the MSC Datamart
Storm track data generated from the Regional Deterministic Prediction System
The Storm track product is an automated system that detects, identifies, tracks and characterizes low-pressure systems based on the outputs of numerical weather prediction models (deterministic and ensemble) or analyses. It makes it possible to produce maps and animations describing the evolution of extratropical and tropical cyclones throughout their lifetime.
Once determined at each forecast timestep of the model, the storm centres are linked together using the method developed by Mark R. Sinclair, which seeks the best possible extension of a trajectory, taking into account the previous position, the speed of movement, the direction of movement and temporal continuity. Only systems with a lifespan of at least 24 hours are retained as valid storms.
Data location
MSC Datamart data can be automatically retrieved with the Advanced Message Queuing Protocol (AMQP) as soon as they become available. An overview and examples to access and use the Meteorological Service of Canada's open data is also available.
The data is available using the HTTPS protocol and resides in a directory that is plainly accessible to a web browser. Visiting that directory with an interactive browser will yield a raw listing of links, each link being a downloadable GeoJSON file.
The data can be accessed at the following adress :
where :
- HH: Model run start, in UTC [00, 06, 12, 18]
- hhh: Forecast time [000, 006, ..., 084]
Technical specifications
The following information is available for each storm centre:
- A marker indicating the position of the center
- A line connecting the successive positions of the center
- The position of the centre
- Date and time (UTC)
- The duration of the storm
- Pressure and vorticity
- For vorticity based tracking only: circulation values
- For tropical cyclones only: the values of low-level baroclinicity (600-900 mb), low-level (600-900 mb) and high-level (300-600 mb) thermal wind structure, maximum vorticity at 850 mb, maximum thickness 250-850 mb, and maximum surface wind, as well as cyclone classifications
Extra-tropical cyclones
Extra-tropical cyclones are tracked base on either their minimum central mean sea level pressure (MSLP) or on their maximum values of gradient wind vorticity.
For vorticity based tracking, cyclones (i.e. vorticity maxima) must reach a given threshold value (at 1000 mb: +0.75x10-5 s-1, at 500 mb: +1.5x10-5 s-1). Vorticity fields are smoothed using a Cressman filter with a smoothing radius of 800 km to removed (real and ficticious) small scale details and retain only the synoptic scale features.
For pressure based traking, cyclone centers are determined from filtered MSLP fields obtained with a Cressman filter and a smoothing radius of 300 km. However, the minimum central pressure values mapped are the raw MSLP values at the center locations found in the filtered MSLP fields.
In all cases, cyclones must last at least 24h to be considered.
Tropical cyclones
The tropical cyclone tracking algorithm uses the same core than the extra-tropical pressure-based tracking algorithm. In order to identify cyclones with tropical characteristics, 4 additional parameters are considered here:
- 850 mb relative vorticity filtered with a Cressman filter using a 300-km radius
- 250-850 mb thickness
- Surface (10 m) wind speed
- Low level baroclinicity (noted B) measured in terms of asymetry of the 600-900 mb thickness field. The definition of B employed here follows Sinclair, M. R., 1997
To be defined as a tropical cyclone, a low pressure centre must meet the following 4 criteria:
- Possess a maximum of 850 mb relative vorticity greater than +2,5x10-5 s-1 whitin a radius of 150 km
- Possess a maximum of 250-850 mb thickness greater than 935 dam whitin a radius of 150 km (indicating a deep warm core structure)
- Generates a surface (10 m) wind speed greater than 22 knots within a radius of 225 km
- Evolve in a barotropic or weakly baroclinic environment, defined here by a value of B lower than 25 m
A track is started only when all the above criteria are met.
If they evolve in a barotropic environment (B < 25 m), tropical cyclones can be classified according to their maximum wind value in categories 1 to 5 of the Saffir-Simpson scale. Below 64 knots, tropical cyclones are considered "tropical storm". Below 34 knots, tropical cyclones are considered "tropical depression". A cyclone operating in a baroclinic environment (B > 25 m) will be considered "hybrid" ( in transition to "extra-tropical").
When a tropical cyclone no longer meets all of the main criteria, it is classified as post-tropical. It is then classified as "extra-tropical" if it evolves in a baroclinic environment (B > 25 m) or classified as "remnant" if it lives in a barotropic environment.
Filename nomenclature
The files have the following nomenclature :
- Tropical cyclones:
{YYYYMMDD}T{HH}Z_MSC_RDPS-StormTracks_TropicalCyclone_PT{hhh}H.json - Extra-tropical cyclones:
{YYYYMMDD}T{HH}Z_MSC_RDPS-StormTracks_GradientWindVorticity-IsbL-0500_PT{hhh}H.json{YYYYMMDD}T{HH}Z_MSC_RDPS-StormTracks_GradientWindVorticity-IsbL-1000_PT{hhh}H.json{YYYYMMDD}T{HH}Z_MSC_RDPS-StormTracks_Pressure-MSL_PT{hhh}H.json
where:
- YYYYMMDD : Year, month and day of the beginning of the forecast
- T: Time delimiter according to ISO8601 norms
- HH : UTC run time [00, 06, 12, 18]
- Z: Time zone (UTC hour)
- MSC: Constant string indicating that the data is from the Meteorologcal Service of Canada (MSC)
- RDPS-StormTracks: Constant string indicating that data is from Regional Deterministic Prediction System (RDPS) forecasts of storm tracks
- TropicalCyclone: A constant string of characters indicating predictions of tropical cyclone tracks
- GradientWindVorticity-IsbL-0500: Constant string indicating predictions of storm tracks detected by their wind vorticity gradient at 500 mb
- GradientWindVorticity-IsbL-1000: A constant string of characters indicating predictions of storm tracks detected by their wind vorticity gradient at 1000 mb
- Pressure-MSL: Constant string of characters indicating forecasts of storm tracks detected by their mean sea level pressure
- PT{hhh}H: Forecast hours based on ISO8601 norms. P, T and H are constant character designating Period, Time and Hour. "HHH" represents the hour at which the storm track is forecasted
- json : constant string indicating the GeoJSON format
Filenames examples:
- 20251016T12Z_MSC_RDPS-StormTracks_TropicalCyclone_PT048H.json
- 20251012T12Z_MSC_RDPS-StormTracks_GradientWindVorticity-IsbL-0500_PT024H.json
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