Convective Outlook Valid for Today and Tomorrow

Regional Impacts:

 

Today

NL: Isolated/embedded thunderstorms.

NB: Chance of afternoon thunderstorms.

PEI/NS/Labrador: None

 

Tonight

NL: Isolated/embedded thunderstorms.

NS/NB/PEI/Labrador: None

 

Thursday:

NB/NL: Isolated thunderstorms.

NS/PEI/Labrador: None

 

Convective Discussion:

Isolated/embedded thunderstorms are possible over Newfoundland this afternoon. Over northern New Brunswick, surface based convection may develop this afternoon and Friday afternoon. It is also possible for Newfoundland Friday afternoon. MLCAPE near 500 J/Kg is anticipated. For both days there is a cap near 700 mb so it may inhibit initiation. Not much of a trigger other than diurnal heating and a supportive upper low. The shear is very low so if thunderstorms do develop they will be pulse type and very slow moving. Pwat values near 30 mm exist so good downpours are likely with this slow moving system. Small hail and gusty winds are also possible.

 

Thunderstorm outlook for today:

 

Thunderstorm outlook for tonight:

 

 

Thunderstorm outlook for Friday:

 

Convective Outlook Valid for Today and Tomorrow

Regional Impacts:

 

Today

NS: Isolated/embedded thunderstorms.

NB/PEI/NL/Labrador: None

 

Tonight

NS/NB/PEI/NL: Isolated/embedded thunderstorms.

Labrador: None

 

Thursday:

NB/NL: Isolated thunderstorms.

NS/PEI/Labrador: None

 

Convective Discussion:

Isolated/embedded thunderstorms are occurring associated with a warm front extending from a low southwest of Nova Scotia. As the low occludes tonight, the thunderstorm potential will move eastward to include Newfoundland.  On Thursday, elevated thundershower potential will continue for Newfoundland. Over central and northern New Brunswick, surface based convection may develop Thursday afternoon. MLCAPE of 500 -750 J/Kg is anticipated with a favourable diffluent 500 mb environment ahead of an approaching upper low. The shear is very low so if thunderstorms do develop they will be pulse type and very slow moving. Pwat values near 30 mm exist so good downpours are likely with this slow moving system. Small hail and gusty winds are also possible.

 

Thunderstorm outlook for today:

 

Thunderstorm outlook for tonight

 

 

Thunderstorm outlook for Thursday

 

 

Convective Outlook Valid for Today and Tomorrow

Regional Impacts:

 

Today

NB: Isolated thunderstorms central and north.

NS/PEI/NL/Labrador: None

 

Tonight

NS: Isolated thunderstorms.

NB/PEI/NL/Labrador: None

 

Wednesday:

NS/NB/PEI/NL: Isolated thunderstorms.

Labrador: None

 

Convective Discussion:

MLCAPE near 500 J/Kg over central and northern NB is anticipated but no real triggering mechanism exists beyond daytime insolation. The shear is very low so if thunderstorms do develop they will be pulse type and very slow moving. Pwat values near 25 mm exist with this airmass. Dry mid layers would allow wind gusts to 60-70 km/h. For tonight and Wednesday embedded thunderstorms are expected associated with a low approaching from the southwest. Pwat values near 45 mm are expected so good downpours are likely with this system. Conditions have been quite dry in many areas of Atlantic Canada this summer so any rain will likely be welcome.

 

Thunderstorm outlook for today:

 

Thunderstorm outlook for tonight

 

 

Thunderstorm outlook for Wednesday

 

Convective Outlook Valid for Today and Tomorrow

Regional Impacts:

 

Today

None

 

Tonight

None

 

Tuesday:

NB: isolated lightning over northern areas.

Marine: isolated lightning, except scattered lightning with gusts of 70-90 km/h over southern West Scotian Slope and Georges Bank (not shown on outlook).

 

Convective Discussion:

MLCAPE of 200-300 J/Kg over northern NB is anticipated but no real triggering mechanism exists beyond daytime insolation. Dry air entrainment above 700 mb will also limit lift today making lightning unlikely.

Tomorrow a very similar environment will be in place, however a weak cold front moving southward into northern NB may provide enough lift to cause the odd strike. There is the potential for severe storms in the Southwestern slope waters with MLCAPEs locally exceeding 2000 J/Kg and effective shears of 30-40 knots. Storms will be forced by a shortwave currently located to the east of New Jersey that is anticipated to move near the slope waters by Tuesday evening. The primary hazard with these storms will be strong wind gusts and reduced visibilities in downpours.

 

Thunderstorm outlook for today:

 

Thunderstorm outlook for tonight:

 

 

Thunderstorm outlook for Tuesday:

Convective Outlook Valid for Today and Tomorrow

Regional Impacts

Today: isolated thunderstorms over southern marine waters.

Tonight: Isolated thunderstorms possible over western NS and southern NB. Isolated thunderstorms once again for southern marine waters.

Sunday: Isolated thunderstorms for most of NL and some marine waters.

 

Convective Discussion

Some ongoing morning thunderstorms for southern waters today through to Sunday in association with a persistent trough of low pressure. Will likely continue to see the diurnal tendencies for these cells with CTC being favourable (overnight and morning). Some gusty winds are possible especially over the warmer waters.

 

An upper low will approach the MRTMS today bringing some showers, with a risk of a thunderstorm tonight as an area of PVA moves in promoting upper level divergence. The guidance will likely miss this potential in conventional indices. Heavy downpours would be the threat and given the slow movement, localized heavy amounts are also a possibility.

 

The trough that has been south of the region will move northward towards NL on Sunday with the risk for isolated thunderstorms giving heavy downpours.

 

Thunderstorm Outlook for Day 1

 

Thunderstorm Outlook for Day 1 night

 

Thunderstorm Outlook for Day 2