Regional Impacts
NL: isolated thunderstorms with locally heavy downpours and strong winds
Labrador: isolated to scattered thunderstorms with locally heavy downpours and small hail.
Southern and eastern marine regions: strong winds and heavy downpours
Convective Discussion
A low pressure system over western Labrador will slowly move eastward today and weaken, while a cold front that moved off of Nova Scotia this morning will continue eastward across the marine slope waters and north across Newfoundland today. This front is currently being maintained over the slope waters by favourable upper dynamics the assist of a strong 250 mb jet axis over Nova Scotia and strong bulk shear of 45KT. The upper levels beyond 500 mb are warm based on the Stephenville sounding but that should degrade some with a cold trough this afternoon depending on breaks in cloud cover to increase surface based heating to further destabilize the air mass. Thunderstorms currently over southern portions of Newfoundland could continue or reignite this afternoon.
Some convection is expected for southern Labrador south along a elongated trough axis where the thickness ridge will move to the northeast. Some clearing this morning will also help to increase instability in the area where CAPE values are indicating near 1000J/kg. Storm are expected to be non-severe multi-cell type but with little bulk shear, there is the possibility of heavy downpours and small hail given lowering freezing levels.
Thunderstorm Outlook for Day 1
Thunderstorm Outlook for Day 1 Night
Thunderstorm Outlook for Day 2
Weak short wave trough moves into Newfoundland. Any surface based heating over inland areas could trigger some non-severe convection that will move to the northeast during the day. Although precipitable water will be lower than today, with values still near 30 mm and CAPE values near 500 J/kg, there could be some local heavy downpours and brief wind gusts.
