Regional Impacts
Today
NB: Isolated to scattered thundershowers giving brief strong wind gusts and small hail.
Lab: Isolated thundershowers over the extreme western sections.
NS/PEI/NL : Nil
Tonight
NB/NS/PEI/NL/LAB: Nil
Tomorrow
NB : Isolated thundershowers over northern and southern sections of the province.
NS: Isolated thundershowers along the western coast of the province.
Lab: Isolated thundershowers over the western sections.
Convective Discussion
Today, a weak riding over the Maritimes is expected to erode throughout the day. As this ridging erodes there is expected to be a sea-breeze form in the late afternoon which, along with day-time heating, will act as a trigger for convection in New Brunswick. The areas that have the formation of sea-breezes, and topographic enhancement will have the greatest chance to form storms that are able to produce longer lasting storms able to produce these winds near 70 km/h and hail over 1cm. With moderate dew points, and more than sufficient MUCAPE and MLCAPE, the main limiting factors for today is going to come down to windshear. There is troughing at the 850mb and 700mb levels which is allowing for convection to become more organized; however, without strong enough jet support todays storms are primed to be single cell and isolated in nature. Likewise for Western Labrador, the thunderstorms for today do not appear to have sufficient jet support to give rise to significant storms and are expected to be isolated in nature.
Tonight, with temperatures and sea-breezes being the most significant trigger for today, once temperatures begin to cool and the sea-breeze ceases the mechanisms for today’s storms will begin to shutdown. There is a risk in the early evening that any existing storms could become more elevated and persist slightly into the later evening hours. However, any storms that become elevated are expected run out of support quickly into the evening hours.
Tomorrow, there is an approaching frontal system coming from Ontario. With this system moving in there is a risk for isolated embedded thunderstorms as the warm sector approaches the Maritimes. Additionally, as this system is approaching there is expected to be a Northwest flow that forms over the Eastern Maritimes and Southwestern Newfoundland regions. This flow could give rise to isolated thundershowers in upslope flow, however predictability on this setup producing thunderstorms is low and as such was not put into the outlook.
Thunderstorm Outlook for Today
Thunderstorm Outlook for Tonight
Thunderstorm Outlook for Tomorrow
Forecaster: Lambert/McArthur