Regional Impacts
Today
NB: Isolated non-severe thundershowers possible
NS: Isolated thunderstorms possible over southwestern sections of province – biggest hazard is wind gusts 60-75 km/h near a storm cell
Tonight
Atlantic Canada: None forecast
Saturday
Atlantic Canada: None expected
Convective Discussion
Embedded thundershowers are on the go this morning/early aft on the Bay of Chaleur coastline. Additionally, as the frontal feature leaves the St Lawrence river valley, a few cells are firing up outside of the greater cloud shield near the Maine border. These cells lack formal dynamics necessary for any significant development. 5-15mm of rain can be expected, locally. NS is a bit more interesting as a few more factors are at play this afternoon. Firstly, there is a lot of wildfire smoke in the mid-levels of the atmosphere. If this can be overcome, there is 300 J/kg of well mixed CAPE available from the Sackville area down to Yarmouth. Nothing will last very long near the coasts as water is still very cold this time of year. Storms today will be very high based, as the boundary layer remains unseasonably dry – albeit dew points are climbing since yesterday (now near 12-14). Shear is another limiting factor. There is very little shear. Anything triggered from this backdoor cold front will only transit along the front, and not for very long. Biggest hazards today are gusty winds (sub-warning) near a storm, small hail(less than 1cm) and lightning. Synoptic rain is on the way for the Maritimes this weekend and shuts of any further TS risk. Newfoundland’s weather remains dominated by a large re-circulating cloud shield.
Thunderstorm Outlook for TODAY
Thunderstorm Outlook for TONIGHT
Thunderstorm Outlook for SATURDAY
Forecaster: TIRONE