Atlantic Canada Weather Blog: Convective Outlook Valid for Today , Tonight and Tomorrow

Regional Impacts

Newfoundland and Labrador… some thunderstorms can be expected in southern Labrador with strong winds and possibly heavy downpours.

PEI…none expected.

NS… a low chance of an isolated thunderstorms inland.

NB… a risk of thunderstorms tomorrow, some isolated downpours possible.

Convective Discussion

Yesterday was fairly active across Labrador, although most thunderstorms occurred well north of the forecast regions. Today, the southern part of Labrador is more likely to see similar activity. The zonal upper jet will remain quasi-stationary through central Labrador and is generally aligned with the flow down to the surface. While updrafts are not expected to be particularly strong, low-level winds exceeding 30 knots could mix down to the surface in some thunderstorms.

Over the Maritimes, dynamics are less favourable; however, potential energy is relatively strong, with mixed-layer CAPE values near 1000 J/kg. A lack of forcing will limit the ability for convective clouds to reach their level of free convection, with the exception of a very slight chance over southwest Nova Scotia.

Tomorrow, weak surface troughing may provide slightly more favourable conditions for scattered thunderstorms across New Brunswick. These are expected to be very isolated and are unlikely to produce widespread rainfall.

Thunderstorm Outlook for Today