We receive two types of model output from ECCC: reverse trajectories (RT) and forward trajectories (FT):
(i) ‘Reverse trajectories’ (RT) refer to air currents that are tracked back in time from specified Canadian locations over a five-day period prior to their arrival date.
(ii) ‘Forward trajectories’ (FT) have a similar purpose; however, the modelling process begins at sites in USA and Mexico. The model output predicts the pathway of a trajectory. Again, of interest are the winds that eventually end up passing over the Prairies.
Current Data
Pacific Northwest (PNW) – The total number of RT’s from the Pacific Northwest of the United States, for the period between May 1 - 22, 2018, was n=67. This was significantly less than in 2017 (n=226), as well as the long term average (n=166) (Fig. 1).
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| Figure 1. Daily total number of reverse trajectories originating over the Pacific Northwest of the United States that have entered the prairies (May 1-22, 2018). |
Weather forecasts (7 day):
Grande Prairie: https://weather.gc.ca/city/pages/ab-31_metric_e.html
