Convective Discussion
Technical Discussion
Two areas will have a chance of convection, for northwestern New Brunswick for this afternoon ending this evening, and for the Atlantic coasts of Newfoundland and Nova Scotia.
For New Brunswick there is marginal moisture and low CAPEs from the 12Z Caribou sounding. But there is an upper level thermal trough approaching from the northwest giving some cooling aloft, combined with some good insolation and a weak trough as a trigger. Showers should not be heavy, but the cells are moving slowly, so there is a chance of training.. Given high shear near 60 knots and low CAPEs, warning level downdrafts are unlikely, but there may be some good gusts .
For Atlantic waters there is a developing low moving across the Scotian Shelf to lies near the Southwestern Grand Banks. Isolated thundershowers are occurring near and a little west of the low center, and are mainly elevated convection. Precipitable water is good, between 35-40 mm. Heavy showers are likely offshore, but gusty winds due to convection are unlikely. Leave that for the main low.
Regional Impacts
New Brunswick: a few thundershowers with a chance for gusty winds northwest.
Nova Scotia: slight chance of thundershowers along the Atlantic Coast this afternoon into the evening.
Newfoundland: slight chance of thundershowers for southern Burin Peninsula and southern Avalon Peninsula tonight into Tuesday morning..
Doug Mercer