A dip in the jet stream will trigger showery weather on Thursday and Friday in the Maritimes as temperatures cool but muggy conditions linger. The dominant pattern of the jet stream (faster winds higher in the atmosphere) this week across North America features a strong ridge (rise to the north) over the Prairies that falls into a broad trough (dip to the south) over the Great Lakes. The ridge in the west is allowing for temperatures to soar in parts of Alberta, Saskatchewan and Manitoba. Heat warnings have been issued for southern parts of all three provinces. The ridge then falls into a trough over the Great Lakes. A broad area of low pressure is within that trough and is producing scattered showers and thunderstorms in eastern Ontario and southern Quebec. Shift into Maritimes The trough in the jet stream will shift eastward Thursday and Friday, allowing the meandering area of low pressure within it to move closer to the Maritimes. Expect cloudier conditions for the region on Thursday, with isolated showers in both New Brunswick and Nova Scotia with a low chance of showers for Prince Edward Island. There will be scattered showers across the Maritimes on Friday and a risk of embedded thunderstorms within the showers on both days. Temperature cools, humidity remains It’s not stifling but a bit of mugginess has worked back into the Maritimes. Dew point temperatures on Tuesday rose into the mid-to-high teens. That’s about the point where many will notice some humidity or mugginess, especially when the sun shines through. Dew point temperatures are forecast to remain at the current level into and through the weekend. In the meantime, the presence of cloud cover and showers will cool high temperatures in the region on both Thursday and Friday. High temperatures for most communities on both those days are likely to be in the low-20s. With the remaining humidity, humidex values will still make it feel like they are in the mid-to-high 20s.
