Convective Outlook Valid for Today and Tomorrow

Regional Impacts

Today.. No thunderstorms expected

Tomorrow.. Isolated thunderstorms with locally heavy downpours.

 

Convective Discussion

 

Not much expected today however the dynamics will improve tomorrow as the upper ridge moves away ahead of the approaching cold front. With respect to the moisture we are looking at high precipitable water values and high surface moisture. Vertical velocity could be somewhat limited but most unstable capes could be in the 500-1000 J/kg range, with low level shear above 30 knots some longer lived cells could be a concern, possible producing gusty winds and heavy downpours with local amounts exceeding 25mm/hr.

 

Thunderstorm Outlook for Day 1

 

 

Thunderstorm Outlook for Day 2

 

Convective Outlook for Weekend of Aug 28-29th

Thunderstorm Outlook for TODAY – Saturday, August 28, 2021

 

Regional Impacts

None expected at this time.

 

Convective Discussion

A strong ridge is building in from the west today, and with it is increasing atmospheric stability. Additionally, a northerly flow last night over much of the region dried out the muggy airmass. The cold front is exiting Newfoundland’s marine waters this afternoon, and there are no other forcings at play today.

 

 

 

Thunderstorm Outlook for TOMORROW – Sunday, August 29, 2021

 

Regional Impacts

None forecast.

 

Convective Discussion

Ridge still keeping atmosphere stable and dry in lower and mid levels. Invading high cloud also a deterrent.

 

 

*Forecaster: TIRONE

 

end/ASPC

Convective Outlook Valid for Today and Tomorrow

Regional Impacts

 

Maritimes:  None today and Saturday.

NFLD/Labrador: A risk of thundershowers this afternoon and evening over central/eastern Newfoundland and southern Labrador. None on Saturday.

 

Convective Discussion

 

Just a chance of embedded thundershowers in Newfoundland today. Over southern Labrador, a few surface based thundershowers are possible this afternoon but the shear is very low so they will be short lived.

 

Thunderstorm Outlook for Day 1

 

Convective Outlook Valid for Today and Tomorrow

Regional Impacts

 

New Brunswick:  Isolated to scattered thundershowers this afternoon and evening.  Potential severe thundershowers giving downpours, gusty winds and hail.

NS/PEI/ NFLD/Labrador: A risk of thundershowers this afternoon and evening.

 

Convective Discussion

 

A cold front will approach northern New Brunswick this afternoon. ML cape values near 1000 J/kg are expected and wind shear near 30 kts.  Freezing levels are high but decent cape exists in the hail growth zone. Dry mid layers will allow for gusty conditions. PWAT values will be near 40 mm so rainfall is a concern. The upper dynamics are supportive as well this afternoon as a strengthening diffluent trough approaches ahead of the main 250 mb jet. There is also possible rotation as the helicity values will be over 100.

 

Thunderstorm Outlook for Day 1

 

 

 

Thunderstorm Outlook for Day 2

 

 

 

Convective Outlook Valid for Today and Tomorrow

Regional Impacts (Day 1)

 

None

 

Convective Discussion (Day 1)

 

None

 

Thunderstorm Outlook for Day 1

 

 

Regional Impacts (Day 2)

 

New Brunswick:  Isolated to scattered thundershowers tomorrow afternoon and evening.  Potential severe thundershowers giving downpours, gusty winds and hail.

NS/PEI/Labrador: A risk of thundershowers tomorrow afternoon and evening.

NFLD: Nil.

 

Convective Discussion (Day 2)

 

A cold front will cross northern New Brunswick tomorrow afternoon and evening. ML cape values near 1000 J/kg are expected and wind shear near 30 kts.  Freezing levels are high but decent cape exists in the hail growth zone. Dry mid layers will allow for gusty conditions. PWAT values will be near 40 mm so rainfall is a concern. The upper dynamics are supportive as well.

 

Thunderstorm Outlook for Day 2