Convective Discussion.
There is a slight risk of TSRA across CNTRL LAB today in conjunction with an approaching upper area of low pressure, and associated troughing in the middle and upper-levels. The closest TEP to try and analyze was YVZ, but it’s likely too far downstream. However adjusting for a surface temperature of 24 and adding a little moisture in the low levels could produce and few hundred joules of CAPE. Very little in the way of shear so I would expect just some ISOL pulse cells. SAT pix is showing some clearing skies so would expect convection to initiate once the Tc has been reached…early to mid afternoon.
A nearly stationary trough of low pressure south of NS and NL will continue to produce some SCT TS through today and tonight. The TEP out of KCHH has a 50+ LLJ at 850 mb, which is a little discerning. It wouldn’t take much to mix that wind to the surface. The afternoon marine forecast for waters south of NS will included PSBL wind gusts near thunderstorms. The SE Avalon may get clipped with some embedded TSRA tonight (say from St. Shott’s up through Cappahayden)…but it’s a marginal risk at best. PW is in the order of 40 to 50 (from the YQI TEP) so areas where there are no TS could see very heavy rains today and tonight (NS and SE NL). OTZ quiet weather for the rest of the region.
Regional Impact.
CNTRL LAB: risk for non-severe TS this afternoon.
NS and SE NL: LCL HVY RA today and tonight…with slight risk of TSRA for the SE Avalon tonight.
Elsewhere: nil sig wx.
Jeremy