Convective Outlook Valid for Today and Tomorrow

Thunderstorm Outlook for Today

 

Regional Impacts:

 

Isolated thunderstorms are possible over Northwestern NB late in the day. Some of these individual storms could give a very brief shower and gusts around 60 km/h.

 

Convective Discussion:

An upper trough will approach from the west late in the day and will be the focus for any convective development. Lightning flashes are currently detected on CLDN between Lac Saint-Jean and Chibougamau. This feature will act as a potential trigger over northwestern NB late this afternoon and into this evening. At this time, the airmass over NB is relatively dry in the low and mid levels, however forecast maximum temperature of 22 combined with dewpoint values of 10 or 11 should be enough to kick start convection. The Upstream soundings from this morning indicate surface-based CAPE values between 300-500 J/kg which would be enough to push the CB tops to 7-8 km. Storm motion would be towards the southeast at about 30 km/h.

 

 

 

Thunderstorm Outlook for Day 2

 

For Wednesday, no thunderstorms expected during daylight hours.

 

Convective Outlook Valid for Today and Tomorrow

Thunderstorm Outlook for Today

 

Convective Discussion

Brief heavy downpours are likely today throughout the Maritimes. There is a slight risk of a thundershower over western sections this evening.

 

 

 

Convective Discussion

Brief heavy downpours are likely today throughout the Maritimes. There is a slight risk of a thundershower over western sections this evening.

 

Thunderstorm Outlook for Tuesday

 

Convective Outlook Valid for Today and Tomorrow

Thunderstorm Outlook for Day 1

No impacts except for southern Maritimes marine waters.

 

Regional Impacts

 

Newfoundland and Labrador and the Maritimes: none for today and Sunday.

Nova Scotia Marine:  reasonable chance for thunderstorms over slope waters, diminishing to a chance south of coastal waters.

 

Convective Discussion

A combination of low moisture, negligible instability and high shear for the Maritimes will prevent any significant convection. For Labrador a ridge building in from the west, combined with low moisture and instability and cooling will prevent anything significant.

 

For the slope water near the North Wall of the Gulf Stream, surface temperatures and precipitable water levels of 30-40 mm and light to moderate shear support scattered air mass thunderstorms along the North Wall of the Gulf Stream, with decreasing likelihood going farther north. This should continue today, tonight and tomorrow.

 

Thunderstorm Outlook for Day 2

 

 

 

Convective Outlook Valid for Today and Tomorrow

New Brunswick.. Severe thunderstorms are possible with strong wind gusts and brief heavy downpours during the late afternoon and early evening.

 

Prince Edward Island.. There is a risk of thunderstorms in western areas this evening.

 

Nova Scotia.. There is also a risk of thunderstorms over western and northern parts of the province this evening.

 

Western Labrador.. Risk of a thunderstorm this afternoon.

 

Convective Discussion

 

Based on this morning’s upper air soundings, there is a potential for destabilization but only later in the afternoon or early this evening. The main supporting features are analyzed just east of the Great Lakes this morning and it will take some time before they reach our region. Parts of New Brunswick have a greater potential for thunderstorm initiation, though the limitations appear to be more significant in the north and therefore the threat is reduced.

 

 

 

Convective Outlook Valid for tomorrow

Regional Impacts

 

New Brunswick.. Severe thunderstorms are possible with strong wind gusts during the afternoon and early evening.

 

Prince Edward Island.. It is possible that some thunderstorms will move into western areas during the evening hours.

 

Nova Scotia.. It is possible that some thunderstorms will move into western and northern parts of the province during the evening hours.

 

Western Labrador.. Isolated thunderstorms possible.

 

Convective Discussion

 

Tomorrow is shaping up to be an interesting day for New Brunswick with dynamics to indicate that there is the potential for supercell development with strong wind gust potential. The main concern is either strong individual storms or a possible squall line developing late in the day.

 

Thunderstorm Outlook for Day 2

 

 

Mel Lemmon