Focus this week has shifted from the heat in the west to the increase in tropical activity and its influence – or should I say – interference on the weather pattern in the high latitudes.
As a weak Madden Julian Oscillation (MJO) has moved into the Western Hemisphere
(noted by the blue line), an uptick in tropical weather has ensued. Tropical Storm Franklin is heading for the Yucatan as of this typing.
And the European has been bullish on a developing tropical system threatening the US East Coast early next week.
Shown above are the many positions (denoted by the lows on the map) the storm could be in by Monday morning. Certainly gets everyone’s attention. But it also wreaks havoc with the steering currents in the upper atmosphere.
It’s widely known that tropical weather systems release tremendous amounts of heat energy into the atmosphere. This is their purpose, after all, to transport the abundant, burgeoning summer heat near the equator to the poles, thereby balancing the global heat budget. As tropical systems “recurve” to the higher latitudes, that release of heat energy buckles the jet stream and creates blocks or deep areas of high and low pressure. The models have a hard time reconciling this, and the forecast can be fraught with error in the extended range. Personally, I’ve seen it tangle the forecast in the short term too, as tropical systems interact with simple fronts and energize weak pressure systems.
Needless to say, we should all proceed with caution. While the weather maps plot the demise of the western heat, they are also starting to hint at some mid-August warmth in Ontario and Quebec. This might be a little overdone at the moment, considering the aforementioned tropical system could draw down the cool air over that same region in response to the departing storm. Bears watching, because the warmth appears consistent until almost the end of the month!
Still time to sit back and watch it unfold, but opportunities in Eastern Canada in late summer are few and far between.