Convective Outlook Valid for Today , Tonight and Tomorrow

Regional Impacts

NB

Today…slight chance of severe thunderstorms late this afternoon and evening with heavy rain and strong wind gusts

Tomorrow… Occasional thunderstorms bring heavy downpours and some strong winds

 

Labrador

Tomorrow… Thunderstorms wind strong winds and some small to moderate hail, heavy rain possible.

 

Convective Discussion

With the very high moisture making its way over the region and the slowly approaching low pressure system we are in for a multi-day event for convective weather, beginning late today in northwest NB and slowly spreading eastward tomorrow and finally into Thursday. Quebec is expected to see severe thunderstorms today with the edge of the severe thunderstorm risk just coming into NB later today. There is some indication that some thunderstorms could organise into supercell/bow echo cells but with a significant area on convective inhibition around 700 mb it may be a challenge to get thunderstorms going. However the potential for strong surface will be a concern as the day unfolds.

 

Tomorrow things shift a bit becoming more favourable for a multicell situation with the potential for heavy rain, should storms become organised (ie training thunderstorms) some areas of New Brunswick could receive more than the highlighted amounts in the forecast for day 2. For Labrador tomorrow the environment will move to a supercell/bow echo situation so strong wind gust to warning level a certainly possible. Paying close attention to overshooting tops and lightning will be helpful in the absence of radar data.

 

As we move into Thursday the dynamics will become more favourable for severe thunderstorms for the remaining areas of the Atlantic provinces please stay tuned as the situation develops over the next couple of days.

 

Thunderstorm Outlook for Today

 

Thunderstorm Outlook for Tonight

 

Thunderstorm Outlook for Tomorrow

 

Mel Lemmon

 

 

Convective Outlook Valid for Today, Tonight and Tomorrow

Regional Impacts

Slight risk of a thundershower this afternoon over southeastern Labrador.

Risk of a thunderstorm for NW New Brunswick Tuesday late afternoon and evening.

 

Convective Discussion

As an upper trough moves into western Labrador this afternoon, daytime heating (inland temperatures into the mid 20s) and convergence ahead of the trough could help trigger an isolated CB over southeastern Labrador this afternoon. Some strong convective gusts are possible, however, increasing shear above 50kt may shear off any developing TCUs. Moisture is also only low to moderate with precipitable water less than 20 mm.  

 

A ridge of high pressure dominates south of the Maritimes today while an upper warm front weakens as it tracks into the southwestern Maritimes this afternoon and tonight.

 

A trough approaches New Brunswick tomorrow and there is a risk of a thunderstorm reaching northwestern areas by the late afternoon or early evening. Although there is good thermodynamic potential with daytime highs reaching 30C, there is increasing warmth in the lower to mid layers may cap convection.

 

 

Thunderstorm Outlook for Today

 

Thunderstorm Outlook for Tonight

 

Thunderstorm Outlook for Tomorrow

 

 

Roberta McArthur