Regional Impacts
Scattered thunderstorms this afternoon and evening across western and possibly northern LAB. Gusty winds, small hail and brief downpours are likely.
Isolated thunderstorms possible for central NB Friday afternoon.
Convective Discussion
Warm frontal trough crossing LAB today will be followed by an approaching cold which will likely give scattered thunderstorms across the west, and possibly the north coast later in the day. The LA Grande TEP has about 30-35 knots of shear, and also a fairly decent LLJ so some cells could get close to being severe. But the instability is not that great, and CAPE is nothing to write home about (in the vicinity of 500 J/KG – based on lifting from a surface temperature of 22 or so). Lastly there are not too many breaks in the SC deck upstream so unless things break open soon it might be difficult getting deeper cells. For now, a compromise of gusts to 70 km/h or so and small hail seems to be legit.
On Friday a weak surface boundary and short wave trough could give some isolated afternoon storms for a portion of central NB. Locally heavy downpours seems to be the main threat.
A side note: there is some indication of isolated convection tonight and early Friday morning for parts of the island portion of NL associated with a weak short wave, but confidence is pretty low on that scenario.
Thunderstorm Outlook for Today
Thunderstorm Outlook for Tonight
Thunderstorm Outlook for Tomorrow
Jeremy