The new seasonal outlook from the solid ECMWF model has been updated...
In regards to the upcoming winter, the model is fairly non-committal across the interior in terms of temperatures, though it does show localized warm/cold anomalies based on expected surface water temperatures from large bodies of water. For instance, the sea surface temperatures across the waters of Atlantic Canada have been well above normal this season, and that is unlikely to change into the winter. Since the ocean has such an impact on the local temperatures from the Maritimes to Newfoundland, it would make sense for the model to predict above-normal temperatures across the region strictly based on the warm sea surface anomalies and not necessarily on the overall jet stream pattern. The same holds true right around the Great Lakes and the northern Canadian waters.
The model seems to be most confident with the idea of a strong, upper-level high pressure ridge dominating in the winter across the Alaska. This pattern would mean a mild winter for Alaska (much different than last year) while shots of very cold air could get sent down into the western prairies and perhaps the U.S. High Plains.
This pattern is also a dry one for southern BC and the Pacific Northwest.
The model is less bullish on the upcoming El Nino and predicts weak El Nino conditions late fall into the winter and peaking by January. Latest observations seem to support this idea.
The model has also gone back to the idea that the north Atlantic Oscillation would be mostly in the positive phase. The image below shows the typical weather patterns associated with a +NAO.
Tornado threat into Tuesday from southeastern Saskatchewan to northwest Ontario.
Latest weekly clues to the long range forecast through mid-August.
Major storm for the Prairies early next week could bring heavy rainfall and severe thunderstorms.
Severe thunderstorm threat later Thursday and a general look at the upcoming weather pattern.
Latest long-range update and a look at global ocean temperatures.
Pattern change will bring significant rainfall opportunity for Alberta Thursday night and Friday.