Convective Outlook Valid for August 25, 2019

Convective Discussion.

 

No activity expected in the region today.

 

Regional Impacts.

 

Nil.

 

 

Jeremy

Convective Outlook Valid for August 24, 2019

Convective Discussion.

 

Only some scattered cells across the southern Grand Banks and slope waters south of NS today in association with a trough of low pressure. Quiet weather elsewhere.

 

Regional Impacts.

 

NS/NB/PEI/Newfoundland/Labrador: nil

 

Convective Outlook Valid for August 23, 2019

Convective Discussion.

 

There are a couple features worth noting today. First off there is some elevated convection associated with the thickness ridge near the Avalon this morning. This is lying along the 850 thermal ridge and very high PW. Heavy downpours to affect the SE Avalon over the next hour or so. The second feature is a cold front  over western NL. Upper level analysis shows a very strong 250 jet (but not in a favorable position). There is plenty of shear (50+ knots), but the instabilities are not that strong. And sat pix shows a lot of cloud cover. If this does burn off allowing some partial clearing there could be a couple decent cells develop this afternoon (across WRN/CNTRL NL) that could give some strong wind gusts. Small hail is also a possibility.

 

Regional impacts.

 

Newfoundland: locally heavy downpours across the SE Avalon. SCT cells this afternoon for CNTRL/WRN areas giving some gusty winds.

 

Nova Scotia, New Brunswick, PEI and Labrador: nil.

 

 

Jeremy

Convective Outlook Valid for August 22 2019

Convective Discussion.

 

A frontal wave currently over the lower St Lawrence will continue to move eastward today under a very strong upper level wind flow. The surface cold front has moved south of the St Lawrence river this morning and dry/stable air is now found west of it. The low cloud continue to dissipate over the Maritimes as the cold front approaches. Ahead of the front, the air mass remains marginally unstable and with the some limited daytime heating of the surface scattered thunderstorms will develop once a warm layer in the low to mid levels becomes eroded. Current radar indicates early development over the mountains of the Eastern Townships and Maine Highlands. These storms will  propagate eastward as the front pushes through NB later in the day.  

 

Regional Impacts.

 

Newfoundland&Labrador: Isolated non-severe thunderstorms.

 

Nova Scotia: Risk of a thunderstorm over central, northern and eastern regions.

 

New Brunswick: Scattered thunderstorms developing west of the region moving east. The main threat is very high wind gusts.

 

Prince Edward Island: Risk of thunderstorms late today.

 

 

Jean-Marc

 

Convective Outlook Valid for August 21 2019

Convective Discussion.

 

A frontal wave over southern Quebec will reach the Maritimes tonight. Ahead of this feature, an area of showers currently over the lower St Lawrence will reach northwestern NB this afternoon. This morning’s soundings from the area are showing limited potential energy so any daytime thunderstorms activity will be limited to Maine and Quebec.

 

This evening and overnight the air mass will become much more humid and unstable as a trough pushes through. Some residual convective features from the west will also spread across the Maritimes, especially across western NS where downpours are likely.

 

Regional Impacts.

 

Newfoundland: none.

 

Labrador: Scattered showers only.

 

Nova Scotia: Dry today, Numerous thundershowers tonight with downpours likely over western sections.

 

New Brunswick: Scattered showers in the northwest today, risk of thundershowers across the province tonight.

Prince Edward Island: Dry today, risk of thundershowers tonight.

 

 

Jean-Marc