Reverse trajectories (RT)
Between May 16 and 23 there were 57 RT’s from the Pacific Northwest of USA that crossed the prairies. The first chart (Fig. 1) indicates site specific results for PNW RT’s for each day of the past week. Values reflect the fact that PNW RT’s were lower this week than previous weeks. The greatest number of PNW RT’s continued to be across southern AB (Fig. 2).
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| Figure 1. Cumulative number of Reverse Trajectories (RT) originating from the Pacific Northwest arriving across the Canadian prairies from May 16-23, 2017 (Olfert et al. 2017). |
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| Figure 2. Number of Reverse Trajectories (RT) originating in the Pacific Northwest that arrived at sites across the Canadian prairies from April 1-May 23, 2017. |
Forward trajectories (FT)
No FTs originating from Mexico or southwest USA/Mexico are predicted to cross the prairies over the next 5 days. The following map provides an overview of FTs that have crossed the prairies during the 2017 growing season.
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| Figure 2. Total number of reverse trajectories originating from the Pacific Northwest of the USA arriving at sites across the Canadian prairies (April 1-May 23, 2017). |
Weather forecasts (7 day):
Grande Prairie: https://weather.gc.ca/city/pages/ab-31_metric_e.html