Regional Impacts
Today
NB: Some isolated thunderstorms are possible over western regions giving brief winds, heavy downpours and small hail.
Labrador: Some isolated thunderstorms are expected for western regions giving brief winds gusts and small hail.
NS/PEI/NL: None
Tonight
None.
Tomorrow
NB/NS/PEI: Risk of thunderstorms across NB in the afternoon into western NS and PEI in the evening giving brief wind gusts and heavy downpours.
Labrador : Scattered thunderstorms across central and southern regions from early afternoon to the evening giving brief wind gusts and small hail.
NL: None
Convective Discussion
As a low pressure system pulls east of Newfoundland this morning, weak ridging build across the eastern Maritimes, Newfoundland and southeastern Labrador today, limiting convection. To the west, a trough of low pressure will slowly advance southeastward from northern Quebec, with another trough of low pressure across the Great Lakes. Two areas to watch today will be ahead of these two features as they enter western Labrador and western New Brunswick this afternoon. With MLCAPE of 500 J/kg and effective shear of 15-20kt, convection that develops is not expected to be that organized, but could still give be some brief wind gusts and small hail into western Labrador given low freezing levels. For the environment entering western New Brunswick, there is similar CAPE values but a bit more shear of near 35-30kt and precipitable water of near 25 mm, which could lead to some organization across southwestern areas this afternoon. Multicell or possible lines may develop and brief strong wind gusts and small hail are possible, although upper support remains further west today, so are not expected to reach severe limits.
For tomorrow, the ridge holds over Newfoundland, but the two troughs continue further east, with the northern trough over central Labrador and the southern trough across southern Quebec and into northern Maine by the evening. More widespread showers and thundershowers are expected for Labrador with some organization possible into multicell or lines as MLCAPE increased to 1000J/kg and effective shear increasing to near 30 kt. Small hail and strong wind gusts will be the main threats given it will be quite dry in the low levels. For the Maritimes, the trough advances towards Maine with some potential for more organized thunderstorms given increasing shear, but CAPE remains near 500J/kg. There is increasing precipitable water of 35 mm, leading to higher rainfall rates in embedded convection in the evening across southern New Brunswick and western Nova Scotia.
Thunderstorm Outlook for Today
Thunderstorm Outlook for Tonight
Thunderstorm Outlook for Tomorrow
Forecaster: McArthur