Where and when the heaviest rain will fall this weekend in the Maritimes

CTV Atlantic meteorologist Kalin Mitchell shares where and when the heaviest rain will fall this weekend in the Maritimes.

A low-pressure system moving out of the U.S. Midwest will turn into a weekend soaker for the Maritimes. The highest risk of downpours will be from Saturday night into Sunday morning for the province of Nova Scotia. The possibility of heavier rain is created by the gaining strength of the system as it approaches, as well as a stream of moisture expected to move up into it off the U.S. eastern seaboard.

Rain timing

There will be patchy fog and increasing cloudiness to start Saturday, except rain starting to develop in New Brunswick.

Rain will continue to develop for that province, northwest-to-southeast, Saturday morning through Saturday afternoon. The rain will become steady, even heavy at times, with the greatest risk of downpours in the southwest of New Brunswick late Saturday afternoon through Saturday evening.

Nova Scotia and Prince Edward Island will have a chance of patchy showers and drizzle Saturday afternoon. The rain will develop for both the provinces Saturday evening and night. Downpours are expected to develop within the rain for Nova Scotia late Saturday night into early Sunday morning.

The steadiest rain will persist in eastern areas of Nova Scotia into Sunday afternoon. The remainder of the Maritimes can expect periods of rain and showers on Sunday.

Rain amounts

This system has the markings of being a soaker.

Expect general rain totals of 15-to-40 mm, with some areas receiving a rainfall as highs as 40-to-80 mm. The risk of the higher rain totals will be highest in the southwest of New Brunswick and for Nova Scotia. In Nova Scotia, the Atlantic coastal counties as well as Cape Breton are being indicated as having the highest chance of downpours late Saturday night into Sunday morning.

Rainfall totals of 40-to-80 mm within 24 hours brings an increased risk of localized flooding. Rainfall rates in downpours could approach 8-to-15 mm an hour. That makes for a moderate risk of flash flooding and quickly-developing hydroplaning conditions developing on roads. The period of downpours is expected to be limited to a few hours.

Rainfall warnings have been issued for southwestern Nova Scotia. Environment Canada is cautioning the area can expect heavy rain to begin Saturday evening.

Depending on the weekend rain, there are parts of the lower Saint John River that are expected to see increased water levels. The latest forecast and status for the river can always be found at New Brunswick River Watch.

Wind

A high and gusty southerly wind will develop for the Maritimes Saturday evening and night. Peak gusts will reach 50-to-80 km/h, with the strongest wind gusts expected at higher terrain and exposed areas of the Bay of Fundy coastline of New Brunswick and the Atlantic coastline of Nova Scotia.

There is a risk that peak wind gusts could reach 90+ km/h in the area of Inverness County, Cape Breton, from Cap Le Moine to Pleasant Bay late Saturday night and early Sunday morning. The risk of stronger gusts there are due to the topography of the Cape Breton Highlands. A wind warning has been issued for the area by Environment Canada.

The wind on Sunday will be coming from the west and southwest. Wind gusts will diminish into a range of 30 to 50 km/h.