Regional Impacts:
Today
NS: isolated lightning
NB: none
PEI: isolated lightning
Labrador: isolated lightning
NL: none
Tonight
None
Friday:
NS: none.
NB: moderate-high rainfall rates, gusty winds, small hail and lightning.
PEI: moderate rainfall rates, and lightning.
Labrador: isolated lightning
NL: none
Convective Discussion:
A weakening cold front moving through the southern Maritimes may trigger a few thunderstorms this afternoon in eastern NS and PEI. Instability will be limited by dry air intrusion, with profiles quite dry above 720mb. Dynamics look less impressive than yesterday with shear near 20 kts at most. Regardless with a convective temperature of 26, MLCAPE near 700 J/kg may be realized. Further north in southern Labrador elevated convection associated with a vigorous upper trough may continue to produce some isolated lightning. Cloud cover looks too extensive to allow surface based convection.
Tomorrow an upper trough from northern Ontario is expected to move through southwestern new England during peak insolation bringing a risk for severe storms there. In New Brunswick the situation becomes a little tricky as moisture advection ahead of the trough will begin to destabilize southwestern sections of the province in the afternoon; increasing the risk for higher rainfall rates in any storms that do develop. However it appears the best Dynamics, and lift associated with the upper trough itself will remain to the southwest over Maine during peak insolation. It is possible that early evening storms remain surfaced based upon crossing the boarder, which would bring a wind and hail hazard to go with the higher rainfall rates. Storm motion will initially be 20 to 30 kts out of the SW, but increase as dynamics improve later in the day (perhaps as high as 40 kts by 0z Saturday). Later in the evening it is expected storms will maintain a moderate rainfall hazard as they become elevated and move into eastern sections of NB and westernmost PEI.
Thunderstorm outlook for today:
Thunderstorm outlook for tonight:
Thunderstorm outlook for Friday:
