Regional Impacts
NB: Isolated thundershowers for southern regions
NS: None
PEI: Isolated thundershowers for western regions
NF: None
Labrador: Isolated thundershowers over southeastern regions
Marine waters: Isolated thundershowers for Laurentian Fan.
Convective Discussion: Clearing behind an upper trough will allow for modest instability to develop this afternoon (MLCAPES ~350 J/kg), causing isolated convection initiation over areas of enhanced differential heating. A secondary area for potential CBs also exists over southern NB into western PEI later this afternoon into the evening. Here SBCAPES of ~400 J/kg should develop with clearing early occurring early this afternoon, convection looks to be triggered by an upper trough moving eastward from Vermont, aided by a right entrance region of a 130 kt upper jet, and surface convergence that was already evident on the 12z analysis from ~CYFC to Kent County. Primary hazards would be isolated lightning, downpours should be limited by rather low PWATs ~ 20mm.
Tomorrow another cold front is expected to move through north-central Quebec into western Labrador triggering CBs with modest CAPES on the order of 400 J/Kg. High LCLs on the order of 1.5-2 km, unstable PBL lapse rates will present an additional hazard for some strong wind gusts outside of lightning and some small hail, given the position of the HGZ and shear character. CBs associated with this feature further south may also move into NW most NB late tomorrow evening, but felt the risk was low enough to leave it out of the day 2 outlook at this time. Another marginal area left off the outlook tomorrow is immediately inland along the northern coast of NL, where an upper trough, coastal convergence and modest instability of 200-300 J/Kg may allow for the odd strike before a 700 mb thermal ridge moves in bringing capping issues. Again felt probability was a little too low to be included in the day 2 outlook at this time.
The slope waters present reasonable instability at T/td’s of 22/20, with isolated lightning becoming scattered by Wednesday evening, with a persistent LLJ.
Thunderstorm outlook for today
Thunderstorm outlook for tonight
Thunderstorm outlook for Wednesday
