Regional Impacts:
Today
NL: Rainfall rates 25-35mm/hr, wind gusts 70-80 km/h.
Tonight
None
Tuesday:
NB: isolated lightning.
Convective Discussion:
Significant instability exists across Newfoundland today. A 25/18.5 modified 12z RAOB from Stephenville yields a MLCAPE of 1000 J/kg, providing ample energy for storms to develop. Nevertheless effective shear of 20-25 kts should limit storm structure to the pulse variety. Moisture is quiet abundant with PWAT ranging from 35-45mm, giving a primary rainfall rate hazard this afternoon with storms that develop. Steep lapse rates from 900mb to the surface and widespread MLCAPEs in excess of 1000 J/kg present a secondary wind hazard, especially if shear ends up being locally enhanced (allowing for the odd storm to take on some super cellular characteristics). Hail is anticipated to be small if it occurs due to a high HGZ and lower shear values.
Thursday:
Another upper trough moving through Ontario today will weaken and move eastward into northern NB tomorrow. Ongoing moisture advection throughout the day in southwest flow ahead of the upper trough should allow for some free lift late in the afternoon. Bulk shears of 30 to 40 kts in combination with MLCAPES up to 750 J/Kg could yield some stronger storms, however there remains some uncertainty in terms of the timing of upper trough.
Thunderstorm outlook for today:
Thunderstorm outlook for tonight:
Thunderstorm outlook for Thursday:
