Thunderstorm Outlook for Day 1 – JUNE 27th
Regional Impacts
Isolated thunderstorms are expected this afternoon and evening across central and parts of northern New Brunswick. In central NB, a cell or two could approach severe limits today for heavy rainfall of 25-40mm. A few lightning strikes are also possible along an elongated boundary in Labrador.
Convective Discussion
Today's thunderstorm risk is highly dependent on synoptic cloud location. The moisture is certainly available with >20 degree dew points. The limiting factor could be the daytime heating needed to overcome a weak cap at 700mb. If highs near 30 can be achieved, then heavy rainfall is the main hazard. Low-mid level shear values are more favourable for severe weather on Day 2 (dynamics advecting in from west).
Thunderstorm Outlook for Day 2
Regional Impacts
Severe thunderstorms are possible in southern and central New Brunswick. Isolated, non-severe thunderstorms are also possible near the Cobequid pass in Nova Scotia. Hot daytime highs, and dew points remaining near 20 will facilitate this.
Convective Discussion
800-1200J/kg of sfc based CAPE can be realized, with ample sfc-midlevel moisture, 16-18 degree T diffs from 500-700mb, and 35-40kts of 0-6k shear. Pwats near 50mm make heavy rain, small hail – FL at 11,000ft – and gusty winds the main hazards. Low level helicity does not appear elevated at this time. Check back tomorrow for an updated OUTLOOK.
