YELLOW WATCH – SEVERE THUNDERSTORM: Brockville, Prescott, Kemptville, Merrickville, Gananoque, Mallorytown, Charleston Lake & Westport

Brockville – A YELLOW WATCH – SEVERE THUNDERSTORM is in effect for Brockville, Prescott, Kemptville, Merrickville, Gananoque, Mallorytown, Charleston Lake & Westport,  Conditions are favourable for the development of severe thunderstorms that may be capable of producing strong wind gusts and heavy rain.

9:17 AM EDT Thursday 18 June 2026

Impact Level: Moderate

Forecast Confidence: High

What:

Wind gusts near 90 km/h. Heavy rain. Risk of tornadoes.

When:

Late this morning and early this afternoon.

Additional information:

Thunderstorms are expected to develop over the area later this morning as a low pressure system departs the province.

Local utility outages are possible. Damage to roofs, fences, branches or soft shelters is possible.

Be prepared for severe weather. If threatening weather approaches, take cover in a basement or interior room. If outside, protect yourself from flying debris and hail. When thunder roars, go indoors! Lightning kills and injures Canadians every year. Secure loose objects.

Emergency Management Ontario recommends that you take cover immediately if threatening weather approaches.

Please continue to monitor alerts and forecasts issued by Environment Canada. To report severe weather, send an email to ONstorm@ec.gc.ca or post reports on X using #ONStorm. For more information: ontario.ca/page/be-prepared-emergency.