Thunderstorm Outlook for Day 1
Regional Impacts
Scattered showers and embedded thundershowers for today and this evening over western New Brunswick. Heavy rain and brief strong wind gusts are possible.
Convective Discussion
A near stationary low pressure system resides over James Bay with a long cold frontal boundary extending south over southern Quebec and along the eastern United States this morning. Most of the dynamics remains further west over southern Quebec into New England. Ahead of the front over New Brunswick today, there is warm advection in the mid to upper levels, limiting the energy possible in embedded thundershowers. It is also expected to remain cloudy today, prohibiting any surface based convection. There is however increasing 0-6km shear, and a low level jet will help destabilize the environmental flow this afternoon. Linear lines of convection may form but will be quite fast moving. There is also ample precipitable water available of 40 to 50 mm which could prompt some localized heavy downpours.
Meanwhile over Labrador, a warm front will push northward into central Labrador today. There is a very slight risk of elevated convection overnight in the warm sector over southwestern parts of Labrador.
Thunderstorm Outlook for Day 2
The weakening trough will continue to push into Nova Scotia overnight and stall on Friday. A short wave trough will move from Quebec into northwestern New Brunswick late afternoon. At this time, TCUs are expected. With very high shear but weak CAPE, CBs are not expected at this time.
Roberta McArthur