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Wednesday, June 14, 2023

Convective Outlook Valid for Today, Tonight, and Tomorrow

Regional Impacts

NB, NS, and PEI: Scattered thunderstorms today and tomorrow, with locally heavy downpours up to 25 mm, possibly higher.

NL: Isolated thundershowers possible over western Labrador, locally heavy downpours up to 15 mm.

 

Convective Discussion…

An upper trough is moving through the Maritimes today, bringing the risk for some elevated convection. 0 to 6 km wind shear of 30 to 40 kts, in combination with the aforementioned trough are providing ample lift and instability today for some organized convection. Thunderstorms are expected to stay elevated, as a thermal ridge at 850 mb should prevent anything from becoming surface based, however heavy downpours up to 25 mm and potentially higher are possible. An upper low will then approach the Maritimes from the west tonight, bringing the risk for some elevated convection for parts of western New Brunswick and southwestern Nova Scotia into tomorrow morning. This upper low will continue to slowly move east tomorrow afternoon, bringing upper and mid level cooling across the Maritimes. This will allow for convection to be more surface based, with locally heavy downpours of up to 25 mm the main risk.

 

Some isolated thundershowers are possible in parts of western and central Labrador today with an upper low moving through northern Quebec. Locally heavy downpours of up to 15 mm are possible with these thundershowers.

 

Thunderstorm Outlook for Today

 

Thunderstorm Outlook for Tonight

 

Thunderstorm Outlook for Tomorrow

 

Copp

Tuesday, June 13, 2023

Convective Outlook Valid for Today and Tomorrow

Regional Impacts

NB: Scattered thunderstorms tonight and Wednesday, with locally heavy downpours possible, 15-30 mm.

NS: Scattered thunderstorms tonight and Wednesday, with locally heavy downpours possible, 15-30 mm.

PEI: Scattered thunderstorms on Wednesday afternoon, with locally heavy downpours possible, 15-30 mm.

NL: Isolated thundershowers possible over central Labrador on Wednesday afternoon.

 

Convective Discussion…

As a ridge of high pressure continues to dominate Atlantic Canada today, an approaching trough from the west will provide ample instability and wind shear for some elevated convection overnight tonight over the southwestern Maritimes. This trough will continue to push east on Wednesday, spreading the risk for elevated convection across most of the Maritime provinces. A thermal ridge at 850 mb will prevent any convection from becoming surface based, as such the main risk for these storms will be locally heavy rainfall, with 15-30 mm possible.

 

For Labrador, some isolated thundershowers are possible on Wednesday afternoon as a shortwave currently over Hudson’s Bay slowly approaches from the west. Locally heavy rainfall near 15 mm is possible with these thundershowers.

 

Thunderstorm Outlook for Today

 

 

Thunderstorm Outlook for Tonight

 

 

Thunderstorm Outlook for Wednesday

 

 

Copp

Monday, June 12, 2023

Convective Outlook Valid for Today and Tomorrow

Regional Impacts

 

Central/Eastern NB, Western PEI, and Western NS: Isolated thundershowers, with locally heavy downpours of 10-15 mm possible.

NL: None.

 

Convective Discussion: A ridge of high pressure dominates the Maritimes today and tomorrow. Mixed layer CAPE values of 250 to 500 J/kg in central and eastern NB, extending into western NS, will aid in developing some weak thundershowers along terrain, with locally heavy downpours the main risk. Storms are not expected to be long lived due to a lack of wind shear and upper level support.

 

Thunderstorm Outlook for Day 1

 

 

Thunderstorm Outlook for Day 2

 

 

-Copp

Sunday, June 11, 2023

Convective Outlook Valid for Today and Tomorrow

Regional Impacts

Western Labrador… low likelihood of isolated thundershower. Locally heavier downpours possible 10-15mm.

 

Convective Discussion… For the most part today will be relatively quiet with a few isolated thunderstorms developing over western Labrador. The dynamics are not particularly favourable with very little wind shear, and no upper support for long lived thunderstorms. Activity will likely be driven by daytime heating and terrain, with mixed layer CAPE is likely less than 500 J/kg. It is possible that there will be some locally heavier rain and small hail. No Severe weather is expected.

 

 

Thunderstorm Outlook for Day 1

 

 

Thunderstorm Outlook for Day 2

 

 

Lemmon

Saturday, June 10, 2023

Convective Outlook Valid for Today and Tomorrow

Today:

NL: isolated non-severe east of NFLD.

NS: small possibility of isolated non-severe thunderstorms over some areas of NS.  Local downpours possible giving up to 10mm.

NB: Isolated non-severe thunderstorms possible over western NB. Local downpours possible giving up to 10 mm. 

PEI: none

 

Tonight:

None.

 

Saturday:

None.

 

 

Convective Discussion

 

Possibility of non-severe thunderstorms over parts of the Maritimes today.  We continue to sit under a cold pool and there is significant cloud cover over the area with highs only reaching 15 to 17C.  The risk will be for areas where clouds clear up a bit this afternoon.  These areas could realize 300 to 400 J/kg which could be enough for small non severe thunderstorms to form.  With energy values so low and no wind shear to speak of, these storms will likely be short lived.  If any cells do form, they will be slow moving so local downpours are possible giving up to 10 mm.   

 

Thunderstorm Outlook for Today

 

 

Thunderstorm Outlook for Tonight

 

 

Thunderstorm Outlook for Sunday