Rainfall warnings issued as remnants of Hurricane Beryl head towards the Maritimes

A pedestrian shields herself from the rain with an umbrella while walking downtown in Halifax on Monday, October 30, 2017. THE CANADIAN PRESS/Darren Calabrese

A lake's worth of water still in Beryl

While the remnants of what was Hurricane Beryl are a shadow of its former strength when it comes to winds and waves, it still packs a tremendous amount of moisture.

Estimating an average of 40 mm of precipitable water available across a very approximate 1,000,000 square kilometres that the body of the storm covers gives a volume of 40 cubic kilometres worth of water. That is a volume of water on the scale of Bras d’Or Lake in Cape Breton, which has an approximate value of 32 cubic kilometre.

While not all that moisture will be squeezed out of the atmosphere in the form of rain, and what rain does come will be spread over a very large area as the remnants continue to move, it gives a rough idea of the high amount of moisture still contained within it.

The swirl of yellows, oranges, and reds in the eastern United States showing precipitable water available with the remnants of Beryl. (Source: Cooperative Institute for Meteorological Satellite Studies, University of Wisconsin-Madison)

That increases the risk of heavy rain amounts and downpours. Rainfall warnings are in effect for southern Ontario, southern Quebec and flood watches have been issued in the state of Maine. Those areas are along the path of some of the heaviest rain expected.

Weather alerts have been issued for the Maritimes as well.

Rainfall warnings and statements for New Brunswick

Rainfall warnings and special weather statements have been issued for much of New Brunswick with the exception of the northernmost areas of the province.

Areas under the rainfall warning are advised that rain arriving late Wednesday evening into Thursday will total 40 to 70 mm with 100 mm or more possible in the heaviest rain. The heaviest rain would be localized and in the form of downpours that could have rain rates as high as 20 to 40 mm per hour increasing the risk of flash flooding.

A special weather statement covers the southern-most area of New Brunswick. It cautions on the possibility of heavy downpours and significant rainfall accumulations. The area has been on the southern edge of the heaviest rain indicated on computer weather model guidance the last few days.

The heaviest rain finished for New Brunswick by Thursday afternoon.

The band of heaviest rain looks lined up to come squarely through New Brunswick, western Prince Edward Island, and possibly parts of Cape Breton Wednesday night into Thursday.

Rainfall warnings and statements for Prince Edward Island

Prince County has been placed under a rainfall warning. Rain beginning Wednesday night and continuing into Thursday evening totalling 40 to 60 mm, except 80 mm or more in the heaviest rain. Like New Brunswick the heaviest rain will be localized due to downpours contained within the system.

The remainder of the province is under a special weather statement. Computer guidance for the heavy rain expected has occasionally included Queens and Kings counties in the higher amounts over the last few days. Communities in those areas should be aware that heavier rain and downpours are still possible.

The heaviest rain should finish for Prince Edward Island by Thursday evening.

Rainfall warnings and special weather statements issued in the Maritimes ahead of the heavy rain and downpours possible with the remnants of Beryl.

Special weather statements for Nova Scotia

On Wednesday, most of Nova Scotia was indicated as being on the more showery side of Beryl.

Special weather statements are in effect for Inverness and Victoria Counties of Cape Breton. The statements cautioning that heavy rain could impact those areas late Wednesday night into Thursday. Downpours could contribute to some localized flooding.

For the rest of Nova Scotia, it is looking more likely that the inclement weather will be in the form of patchy showers and drizzle. There is a lot of moisture in the area currently due to the humid weather this week. Due to that, some isolated thunderstorms or downpours may still be possible within any occurring showers.

More details on the heat warnings issued for most of the Maritimes can be found here.