Thunderstorm Outlook for Day 1
Regional Impacts
Low risk of high based thunderstorms over the higher terrain in northern New Brunswick and western Newfoundland late this afternoon and evening. Convective downdraft gusts are the main concern should anything develop.
Convective Discussion
A very hot and slightly humid air mass continues to reside over the Maritime provinces today. A trough over southern Labrador into northern Newfoundland will slowly sink southward today and reach northeastern New Brunswick and the Gulf of St. Lawrence tonight. Temperatures profiles over NB this morning suggest a very dry air mass but with a lot of buoyant potential. An isolated thunderstorm cannot be ruled out, especially with the help of forcing from hills and where forest and other vegetation may provide the extra moisture and energy needed or with the help of a sea breeze convergence off the Bay of Chaleur. The forecast highs are such that the convective temperature of 37 could even be reached on its own. Given such a dry and warm profile at all levels, there may not be much in the way of precipitation but convective wind gusts could be a concern. There may be a similar situation off the higher terrain in southwestern Newfoundland.
Thunderstorm Outlook for Day 2
Daytime heating air mass type thunderstorms are possible mainly over Maine tomorrow afternoon but with the slight winds aloft from the west, some of these cells could reach into western New Brunswick in the evening. The risk remains very low as mixing in the low levels may inhibit development. A ridge of high pressure sinks south into Newfoundland and Labrador tomorrow with no convective weather expected.
Roberta McArthur