Convective discussion:
There is the risk of heavy rain and embedded thundershowers over parts of the Maritimes today and tonight with the approach of an upper level trough tracking eastward.
Technical Discussion:
The upper trough that has been persistent over the eastern United States and southern Quebec is beginning to slowly push eastward towards the Maritimes and weaken as it tracks across New Brunswick this evening and overnight. There is the risk of isolated thundershowers along and ahead of the trough this afternoon and evening for New Brunswick and western parts of Nova Scotia. With increasing moderate wind shear of 40-45kt, CAPE values near 500 J/kg as well as high precipitable water of 40-50mm, heavy downpours and brief wind gusts are possible. At this time thundershowers do not look to be severe but the concern will be heavy rainfall where total rainfall values could reach over 50mm in some areas especially over western New Brunswick and southern New Brunswick.
Regional Impacts:
New Brunswick and Nova Scotia: Risk of thundershowers this afternoon and evening with locally heavy downpours possible.
Prince Edward Island: Locally heavy showers in TCu possible.
Southwestern marine waters: Thundershowers this afternoon.
Labrador: Locally heavy showers over central and eastern section in TCu.
Newfoundland: Nil
Roberta McArthur