Monday, April 12th 2021, 2:38 pm - Spring weather will finally appear in Western Canada while eastern regions will see a cooldown.
Spring is off to a very warm start across most of Canada. The various shades of orange and red on the temperature anomaly map below highlight the above seasonal temperatures that have dominated regions east of the Rockies since late February.
However, it has been a very different story across most of British Columbia and Northern Canada where spring has struggled and cooler than seasonal temperatures have dominated.
A major shift in the pattern is already underway. First, warm spring weather is finally bursting onto the scene across the West this week. By mid-to-late week, the South Coast of B.C. will see temperatures ranging from the upper teens to the mid 20s with abundant sunshine.
Meanwhile, much colder weather has shifted east across the Prairies. Widespread snow is likely for Manitoba and eastern Saskatchewan with parts of Saskatchewan and Manitoba seeing totals of 15-30 cm by Tuesday night and temperatures will be more typical of early March.
Late in the week, much warmer weather will spread east into Alberta with many places reaching 20°C on Saturday.
Across Ontario and Quebec, the pattern change will be slower to develop. For southern Ontario, temperatures will be much cooler than last week (but still near seasonal) with several rounds of April showers. However, southern Quebec will remain exceptionally dry and temperatures will still be on the warm side of seasonal. Across Atlantic Canada, temperatures will be within a few degrees of seasonal.
During the third week of April, the very warm pattern will continue across B.C. and at times spread east into the western Prairies. However, a deep trough in the jet stream is expected to develop over Ontario and Quebec.
This will bring an extended period of below seasonal temperatures to the region and that pattern is expected to continue into the fourth week of April, as well. Cooler than seasonal temperatures will also spread into the Maritimes at times, while Newfoundland should be near seasonal.
Fortunately, seasonal temperatures steadily climb by one or two degrees per week as we progress through the month of April, so this pattern change will not take us back to winter, though some places could still see some snow. However, it appears that the second half of April will not bring as much warm weather as what we have seen during the first ten days of the month.
For Ontario and Quebec, this is an all too familiar spring pattern as we have seen extended periods of chilly weather during the majority of the spring seasons in recent years. While many will be disappointed by this period of cooler weather, we do not think that this setback will take over our memory of the season as it did last year. A warmer pattern should return much more quickly than last year during May.