Convective Outlook Valid for Today, Tonight and Tomorrow

Regional Impacts

 

Today

NB: slight risk of an embedded non-severe thundershower across northern areas of the province near the Que border.

NS/PEI/NFLD/LAB: None.

 

Tonight

NS/NB/PEI: embedded elevated non-severe convection is forecast late overnight tonight across the Maritimes, and into early Sunday morning.

NFLD/LAB: None.

 

Sunday

NB/NS/PEI/NFLD: risk of non-severe embedded thundershower activity continues all day in the broad area of convective showers. There could be a few heavier downpours associated in the Annapolis Valley and Cobequid mountain areas. Late day the shower activity could approach Saint-Pierre and the Burin.

LAB : None.

 

Convective Discussion

The atmosphere will slowly begin to destabilize above 850mb over the next 12-24hrs. A broad area of low pressure is approaching the Maritimes tonight from the Great Lakes region of Ontario. This will bring a change in airmass and bump up dewpoints significantly from 4 to 18. Accordingly, embedded non-severe thundershowers are being forecast and will slowly traverse the Maritimes (and the marine district) this weekend. The greatest impact is repetitive showers, and lightning. Rainfall amounts will be highly variable across regions. There is a low level jet at 850 out of the WSW that strengthens both in the day Sat and again on Sunday. BUT – effective shear remains low at only 10-20kts. 0-3k shear is better at 30-40kts which just confirmed the nature of these cells being mostly elevated. CAPE for the whole column is 400J at best and very skinny.

Thunderstorm Outlook for Today

Thunderstorm Outlook for Tonight

Thunderstorm Outlook for Tomorrow

Forecaster: Tirone.

Convective Outlook Valid for Today, Tonight and Tomorrow

Regional Impacts

 

Today

NS/NB/PEI/NFLD/LAB: None.

 

Tonight

NS/NB/PEI/NFLD/LAB: None.

 

Saturday

NB: Slight risk of a late afternoon thundershower in NWern regions with brief heavy downpours.

NS/PEI/NFLD/LAB : None

 

Convective Discussion

Atlantic Canada remains fairly quiet today with a ridge of high pressure across the Martimes with a cold front exiting eastern Newfoundland this morning and a semi quasi-stationary low pressure system siting south of the Maritimes marine district. A weak trough across central and southern Quebec into central Maine along with increasing surface temperatures and cooler air aloft aid in the triggering of isolated thundershowers this afternoon and evening but are not expected to persist into New Brunswick.

For Saturday, the trough will move eastward and provide some scattered showers across New Brunswick in the morning.  An approaching low pressure system moves into southern Quebec by Saturday afternoon, ahead of this system within the warm sector, scattered showers with risk of non-severe isolated thundershowers are possible mainly for northwestern New Brunswick where convective temperatures are mostly like to be reached and there is sufficient lift and effective shear to maintain convection. Weak troughing is also expected across northern Quebec into central and southeastern Labrador, giving isolated showers.

The low pressure system will track across northern New Brunswick and into the Gulf of St. Lawrence Saturday night and into Sunday with possible embedded convection.

Thunderstorm Outlook for Today

Thunderstorm Outlook for Tonight

Thunderstorm Outlook for Tomorrow

Forecaster: McArthur

Convective Outlook Valid for Today , Tonight and Tomorrow

Regional Impacts

 

Today

NS/NB/PEI/NFLD/LAB: None.

 

Tonight

NS/NB/PEI/NFLD/LAB: None.

 

Friday

NS/NB/PEI/NFLD/LAB: None.

 

Convective Discussion

The quiet convective weather will persist over Atlantic Canada today and Friday. A ridge of high pressure over the southern Marine District will drift away as a weak trough currently over the Lower North Shore of Quebec continues moving southward.  Any instability today should be limited to areas of central Quebec and the Gaspe Peninsula.

Thunderstorm Outlook for Today

Thunderstorm Outlook for Tonight

Thunderstorm Outlook for Tomorrow

 

Convective Outlook Valid for Today, Tonight and Tomorrow

Regional Impacts

NS/NB/PEI/NFLD/LAB: None.

Convective Discussion…

A quiet couple of days are in store for Atlantic Canada as a ridge of high pressure settles over the region. Some weak troughing exists over central Labrador this morning, however dry low levels and a lack of instability should prevent any thundershowers from developing this afternoon as the trough slowly drifts south.

Some isolated thundershowers are possible east of Sable Island today around a weak vorticity center, but will remain well offshore.

Thunderstorm Outlook for Today

Thunderstorm Outlook for Tonight

Thunderstorm Outlook for Tomorrow

Forecaster: Copp

Convective Outlook Valid for Today , Tonight and Tomorrow

Regional Impacts

NB, PEI and NS: Scattered showers with a risk of thunderstorms. 15-20mm of rain possible in thunderstorms.

Newfoundland and Labrador: Thunderstorms not expected.

Convective Discussion

Scattered showers and thunderstorms will move slowly across southern New Brunswick into Nova Scotia and possibly PEI today. While updraft strength will be limited, weak upper-level support associated with a jet streak and a 500 hPa trough may aid development. Low freezing levels could allow for small hail. No significant impacts are expected.

Conditions improve tomorrow as fair weather returns.

Thunderstorm Outlook for Today

Thunderstorm Outlook for Tonight

Thunderstorm Outlook for Tomorrow

 

Mel lemmon