Regional Impacts:
Today
Northwestern NB: isolated lightning, locally heavy downpours and gusty winds
PEI/NS/NL/Labrador: None
Tonight
Western NB/NS: Isolated lighting and locally heavy downpours
Tuesday
NB/NS: isolated lightning and locally heavy downpours
PEI/NL/Labrador: None
Convective Discussion:
A low pressure system will advance northeastward over Hudson Bay with a trough extending southward into New England today. There is a risk for convection over northwestern New Brunswick ahead of the trough and will continue eastward into the evening. The limiting factor is a warm nose at 850 mb and 500 mb as seen on the 12Z KCAR sounding. However, should daytime surface temperatures reach 30 degrees, along with the thermal trough at 500 mb pushing eastward, it should be enough to initiate convection over central Maine this afternoon. With increasing 0-6km shear and precipitable water above 40 mm, more organized lines that develop could maintain into New Brunswick into the evening.
An isolated TCU is possible over northeastern New Brunswick as well but there may be too much warming aloft to initiate any CBs.
As the trough continues to approach overnight and into Wednesday, convection will be more elevated and isolated in nature. A short wave will develop south of Long Island this evening and get wrapped into the main trough as it tracks through the Maritimes. This moisture will get drawn northeastward towards western Nova Scotia early Wednesday morning and continue through the Maritimes and towards southern Labrador by Thursday morning. The main threat will be locally heavy downpours with precipitable water values near 50 mm along the Atlantic coast of Nova Scotia.
Thunderstorm outlook for today:
Thunderstorm outlook for tonight:
Thunderstorm outlook for Wednesday:
