Chilly, damp weather continues Friday in the Maritimes. When will it change?

Pluie

While Maritimers may have hoped for a banner end to the month of May, the weather will instead be cloudy, chilly and in some cases rainy. It’s all part of a large weather pattern that is dominating North America this week.

Scorching in the west

A strong ridge in the jet stream has developed over parts of western Canada.

Temperatures continue to soar in the Prairies, with record high temperatures being set and heat warnings issued.

In Saskatchewan, an Orange Warning – Heat cautions communities could reach 35 degrees Thursday and Friday, with overnight lows only cooling to near 18. The public is being asked to check on those who may be more vulnerable to the heat and to watch for signs of heat exhaustion. Yellow Warnings – Heat have been extended into southeastern Alberta and southern Manitoba.

The hot weather is forecast to moderate in Saskatchewan over the weekend. Temperatures are expected to come down in Manitoba through the first part of next week.

Chilly and damp on the East Coast

The ridge in the west dips into a deep trough centred below the Maritime provinces.

There is cooler air pooled in the trough, and it is slowing several low-pressure systems down as the pass by the East Coast. Those slow-moving weather systems are keeping sky conditions cloudy and producing areas of rain and showers.

Temperatures in the Maritimes will remain several degrees below late-May averages through the close of the month.

This type of weather pattern tends to be stagnant, taking several days to break down or move on. Most weather prediction computer modelling suggest the Maritimes can expect a warm-up Wednesday onward next week.

Where it will be rainiest

One of those slow-moving, low-pressure systems will stall out in the vicinity of Sable Island Thursday into Friday.

Rain will wrap around the centre of that weather system and back into eastern parts of the Maritimes. Prince Edward Island and eastern Nova Scotia can expect further periods of rain both Thursday night and on Friday. Additional rain amounts of 10-to-30 mm are expected for most. Rain will diminish to showers and drizzle Friday evening and night.

Temperatures aloft are chilly enough that some wet snow may mix in with the rain for the Cape Breton Highlands.

Parts of Cape Breton could also finish with some higher rainfall totals. Victoria and Cape Breton Counties could potentially see 40-to-70 mm of rain in total before it finishes Friday night, with the potential for ponding water and some localized flooding in areas with poor drainage.

The weekend forecast is cool with cloudy periods and a low chance of showers on Saturday, with any developing showers very spotty in coverage. There is a higher chance of showers for eastern Nova Scotia Sunday afternoon and evening.