Regional Impacts…
Today
NB: Scattered thunderstorms developing, some becoming strong with potential for damaging wind gusts and 1-2 cm hail. Severe weather watch for western portions of the province for the afternoon into the evening.
NS/PEI: risk of non-severe thunderstorms
NF: A slight chance of thunderstorms south coast
Labrador: None
Tonight
NS and NF: A chance of embedded thunderstorms
NB/PEI/Labrador: None
Monday
NS and NF: A chance of embedded thunderstorms
NB/PEI/Labrador: None
Convective Discussion…
Low pressure near Sept-Iles with an attached frontal wave system is slowly moving eastward. In the warm sector, a 50-60kt SWly low-level-jet has been pushing very moist air northward and a large area of area of moderate-heavy rain has spread across NS earlier this morning which resulted in amounts of 10-30mm. This activity will advancing towards NF during the day.
To the west, an upper trough over western Quebec will be advancing towards the Maritimes today and will be the focus severe weather (the main threat is the potential for damaging wind gusts WINDEX gusts estimates 50kt). There is not much convective inhibition ahead of this feature, and towering clouds are already noticeable north and south of the St. Lawrence valley. The main forcing will be a sharp area of convergence at the surface, emerging 30kt Wly low-level-jet, right entrance of a slightly cyclonic upper level jet, and 500mb PVA. Temperature and Dewpoint combination of 23,18 are sufficient to produce surface-based CAPE values of 1,000 J/Kg (MU 1,500) with Lifted index of -3 to -5, and deep-layer shear of 40-60kt. Under this very strong flow, hodograph is indicating straight/linear winds with storm motion of 260/35kt. Some of the storms could be long-lived especially over central Maine later this afternoon. This could produce bowing lines which could advance east of the international border.
Thunderstorm Outlook for Today
Thunderstorm Outlook for Tonight
Thunderstorm Outlook for Tomorrow
