Sunday, July 16, 2023 11:49 AM
Regional Impacts
Today
NB: Heavy downpours, with intense rainfall rates of 25 to 50 mm/h and locally strong wind gusts.
Labrador: Scattered thunderstorms over central and southeastern Labrador giving heavy downpours, small hail and strong winds.
NS: None.
PEI: Risk of downpours for Prince County.
Tonight
NB: Heavy downpours with isolated embedded thunderstorms. Rainfall rates of 25 to 50 mm/h.
NS: Heavy downpours possible for the Atlantic coast and western regions.
Monday
NS: Heavy downpours likely for western and central regions with rainfall rates at 25 to 50 mm/h.
NB: Isolated to scattered thunderstorms with intense rainfall rates of 25 to 50 mm
Convective Discussion
An upper low currently over James Bay will slowly weaken and track eastward as a quasi-stationary ridge holds over Newfoundland extending towards the Grand Banks. The Maritimes remains under a tropical air mass with precipitable water between 40 and 50 mm. An area of heavy showers this morning over the Bay of Fundy into southern New Brunswick will continue to push northward this afternoon. The trough associated with the low over James Bay is giving multiple rounds of heavy rainfall in southern Quebec extending south that will slowly push into western New Brunswick overnight and into Monday over PEI and western NS Monday night. Persistent cloud cover over New Brunswick is not likely to allow any surface based convection today, but there is 25KT 0-6km shear from KCAR so along with heavy rainfall, some isolated strong wind gusts are possible if more organized lines develop.
Over central and southeastern Labrador today, some clearing of cloud this morning will allow temperatures to reach the convective temperature based off Goose Bay’s 12Z sounding and expected high reaching 30C with MUCAPES of near 1000 J/kg. Deep level shear is fairly week, so not expecting strong organization of any convection that develops, but with precipitable water also in the low 30’s so heavy downpours will be a factor.
Behind the trough on Monday, there air mass remains unstable with isolated thunderstorms possible for western New Brunswick and western Labrador.
Thunderstorm Outlook for Today
Thunderstorm Outlook for Tonight
Thunderstorm Outlook for Tomorrow
