Environment Canada has issued rainfall warnings for expected heavy rain and downpours Wednesday in Nova Scotia. Special weather statements are in effect for both New Brunswick and Prince Edward Island where rain totals are generally expected to be less than in Nova Scotia but could still approach 50 mm in thunderstorms.
The rain is not directly a result of Hurricane Franklin but rather the result of a weather front moving in from the west meeting up with a second one out of the northeastern US. Franklin may indirectly feed some moisture into that rain though.
The powerful storm is putting a lot of water vapour up into the atmosphere. Some of that is being direct towards the Atlantic coastline of Nova Scotia by stronger winds aloft. Should downpours or thunderstorms Wednesday tap into that water vapour, it could enhance rainfall amounts.
Rain with the risk of downpours will develop west-to-east in the Maritimes early Wednesday morning into Wednesday afternoon. Rain with a risk of downpours clearing western areas by Wednesday evening, and rain with a risk of downpours clearing eastern areas Wednesday night.
Areas at highest risk of downpours or thunderstorms that could produce local rain totals of 60 to 100 mm includes the South Shore of Nova Scotia, Halifax County, around the Minas Basin, and across the east of the province including Cape Breton.
Widespread rain totals for the province can be expected to be in the range of 40 to 60 mm. Higher rain totals and associated downpours elevates the risk of flooding and flash flooding. Caution should be exercised in any areas that multiple downpours or thunderstorms move over.
Rain for New Brunswick and Prince Edward Island will mostly range 20 to 40 mm. There is a lower risk of thunderstorms and downpours for both those provinces. In the event of a thunderstorm it could produce some totals of 50 to 60 mm in areas it moves over. Should that occur it is expected to be more isolated in nature.
Wind isn’t expected to be a major issue on Wednesday. It will be southerly and sustained 20 to 30 km/h with gusts 30 to 60 km/h.
On the topic of Franklin, the official forecast cone and track from the National Hurricane Center continues to take the storm south and east of land areas of Atlantic Canada.
The most likely event for a pass through the region would be in the Grand Banks as a Category 1 hurricane on Friday. Any marine operations should carefully monitor the ocean state forecast through the end of this week.
The storm is also expected to increase the surf on parts of the Atlantic coastline of Nova Scotia as well as the southern coastline of Newfoundland. That could also increase the risk of rip currents being present.
