Thunderstorm Outlook for Day 1
Slight chance of thunderstorms, except some local downpours for southwest Labradors, and some possibly significant rainfall and gusty winds for western New Brunswick.
Convective Discussion
N-S ridge over eastern Newfoundland with a nearly vertically stacked deep trough from western Labrador to New Brunswick then extending towards Cheasapeake Bay. There are embedded lows for Labrador, New Brunswick, and near Cape Cod. As with yesterday, many of the profiles are moist adiabatic and tropical, with 40-50 mm PWATs and ample surface moisture, with surface dew points near 21 C. Shears are about 25 kts near the trough increasing to 40 for central Nova Scotia then dropping back to 24 for eastern regions.
For Labrador the low has a frontal trough extending east towards Mary’s Harbour, and the low will move steadily east. There is some Cuing up near and west of the low, and some isolated thundershowers are possible. Ahead of the front there should be TCu’s possibly with a strike or two, but with some heavy downpours being the main factor. PWATs are about 40 mm and Capes may approach 500 J/kg, but the capping inversion may have some trouble breaking.
For New Brunswick, especially in the west the story is similar, but with more energy and surface moisture, with energy peaking late in the afternoon near 500-1000 J/kg, with surface dewpoints near 20 C and the main moisture axis through the center of the province. The shear is low at about 25 kts, so supercells probably won’t be an issue. The impacts will be airmass cells with heavy downpours and some gusty winds.
Thunderstorm Outlook for Day 2
