ONTARIO: Thunderstorm Forecast for Monday, June 26, 2023

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE WHICH WILL BE EASIER TO READ.



FORECAST DISCUSSION

Widespread thunderstorm activity is expected across Southern Ontario on Monday. The strongest storms are expected in Central and Eastern Ontario where there might even be a questionable severe risk. However, at this point, we are sticking with a non-severe risk. An isolated severe risk might be introduced in a future update.

ONTARIO: Thunderstorm Forecast for Sunday, June 25, 2023

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE WHICH WILL BE EASIER TO READ.



FORECAST DISCUSSION

A squall line of strong to severe storms is expected to develop across Southern Michigan during the afternoon on Sunday and track eastward. The environment is favourable for these storms to remain severe once they reach Deep Southwestern Ontario by the mid to late evening hours.

Our primary concern will be the widespread wind risk from Sarnia through Chatham and into Windsor. These areas could experience in excess of 100 km/h wind gusts from this line. Up to quarter-sized hail and even an isolated tornado can’t be ruled out with these storms.

Further eastward, the squall line is expected to track across our region overnight. Although it should weaken to below-severe levels by the early overnight hours. The occasional gust of up to 90km/h may still occur in localized spots overnight.

NORTHERN ONTARIO: Thunderstorm Forecast for Sunday, June 25, 2023

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE WHICH WILL BE EASIER TO READ.



FORECAST DISCUSSION

Isolated non-severe thunderstorms are expected along the Southern parts of Northern Ontario on Sunday including Fort Frances, Thunder Bay, Sault Ste. Marie and Sudbury. The main threat will be heavy rainfall as these storms will be moving quite slowly.

ONTARIO: Thunderstorm Forecast for Saturday, June 24, 2023

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE WHICH WILL BE EASIER TO READ.



FORECAST DISCUSSION

Pop-up thunderstorms are expected across much of Southern Ontario during the afternoon and evening on Saturday. These storms are likely to be quite weak and localized so not everyone will see them. Those that do see them can expect small hail, lightning and heavy rainfall.

The environment is favourable for the development of funnel clouds as well. While funnel clouds don’t directly pose a risk to the ground, they can touch down in rare cases and become a landspout tornado.

Landspout: A landspout is a type of tornado that forms under a weak thunderstorm. Unlike traditional tornadoes, which develop from supercell thunderstorms and are associated with a rotating updraft called a mesocyclone, landspouts form from non-supercell storms and do not have a mesocyclone. These tornadoes are generally weaker and shorter-lived than their supercell counterparts but can still pose a threat to property and life, with wind speeds occasionally reaching up to 160 km/h.

NORTHERN ONTARIO: Thunderstorm Forecast for Saturday, June 24, 2023

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE WHICH WILL BE EASIER TO READ.



FORECAST DISCUSSION

Thunderstorms are currently not expected across Northern Ontario on Saturday.

ONTARIO: Thunderstorm Forecast for Friday, June 23, 2023

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE WHICH WILL BE EASIER TO READ.



FORECAST DISCUSSION

Scattered thunderstorms are possible across much of Southern Ontario with the exception of Deep Southwestern Ontario and the Ottawa region. The risk will be primarily during the afternoon and evening on Friday. All of these storms should remain non-severe with the main threats being small hail, lightning and heavy rainfall.

NORTHERN ONTARIO: Thunderstorm Forecast for Friday, June 23, 2023

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE WHICH WILL BE EASIER TO READ.



FORECAST DISCUSSION

Isolated non-severe thunderstorms are expected to develop in parts of Northeastern Ontario during the afternoon and evening on Friday.

ONTARIO: Thunderstorm Forecast for Thursday, June 22, 2023

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE WHICH WILL BE EASIER TO READ.



FORECAST DISCUSSION

Thunderstorms are currently not expected across Southern Ontario on Thursday.

NORTHERN ONTARIO: Thunderstorm Forecast for Thursday, June 22, 2023

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE WHICH WILL BE EASIER TO READ.



FORECAST DISCUSSION

Isolated storms are expected to develop across Northwestern Ontario during the afternoon on Thursday. Some of these storms could present a minor severe risk with up to quarter-sized hail, 90 km/h wind gusts and flash flooding. The environment is also favourable for the development of funnel clouds which in rare cases, can touch the ground and become a landspout tornado.

ONTARIO: Thunderstorm Forecast for Wednesday, June 21, 2023

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE WHICH WILL BE EASIER TO READ.



FORECAST DISCUSSION

Thunderstorms are currently not expected across Southern Ontario on Wednesday.

NORTHERN ONTARIO: Thunderstorm Forecast for Wednesday, June 21, 2023

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE WHICH WILL BE EASIER TO READ.



FORECAST DISCUSSION

Isolated thunderstorms are expected to impact parts of Northwestern Ontario along the Manitoba border on Wednesday afternoon and evening. Current indications suggest they should remain non-severe, but an odd severe storm can’t be ruled out. Although, the confidence isn’t high enough to support an isolated severe risk on our map.

ONTARIO: Thunderstorm Forecast for Tuesday, June 20, 2023

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE WHICH WILL BE EASIER TO READ.



FORECAST DISCUSSION

Thunderstorms are currently not expected across Southern Ontario on Tuesday.

NORTHERN ONTARIO: Thunderstorm Forecast for Tuesday, June 20, 2023

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE WHICH WILL BE EASIER TO READ.



FORECAST DISCUSSION

Thunderstorms are currently not expected across Northern Ontario on Tuesday.

NORTHERN ONTARIO: Thunderstorm Forecast for Monday, June 19, 2023

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE WHICH WILL BE EASIER TO READ.



FORECAST DISCUSSION

Thunderstorms are currently not expected across Northern Ontario on Monday.

ONTARIO: Thunderstorm Forecast for Monday, June 19, 2023

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE WHICH WILL BE EASIER TO READ.



FORECAST DISCUSSION

Thunderstorms are currently not expected across Southern Ontario on Monday.

ONTARIO: Thunderstorm Forecast for Sunday, June 18, 2023

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE WHICH WILL BE EASIER TO READ.



FORECAST DISCUSSION

Localized non-severe thunderstorms are possible in the Ottawa Valley during the late afternoon and evening on Sunday. These storms are expected to be weak, but they could bring some small hail, gusty winds and heavy rainfall.

NORTHERN ONTARIO: Thunderstorm Forecast for Sunday, June 18, 2023

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE WHICH WILL BE EASIER TO READ.



FORECAST DISCUSSION

Isolated thunderstorms are expected to develop in Northwestern Ontario during the afternoon and evening on Sunday. These storms should remain non-severe with small hail, gusty winds and heavy rainfall. Although, there is a slight chance that we may see funnel clouds which in rare cases can touch down and become a landspout tornado. This risk is questionable at best as the environment isn’t that strong but still worthwhile to mention.

ONTARIO: Thunderstorm Forecast for Saturday, June 17, 2023

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE WHICH WILL BE EASIER TO READ.



FORECAST DISCUSSION

Thunderstorms are currently not expected across Southern Ontario on Saturday.

NORTHERN ONTARIO: Thunderstorm Forecast for Saturday, June 17, 2023

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE WHICH WILL BE EASIER TO READ.



FORECAST DISCUSSION

Thunderstorms are currently not expected across Northern Ontario on Saturday.

ONTARIO: Thunderstorm Forecast for Friday, June 16, 2023

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE WHICH WILL BE EASIER TO READ.



FORECAST DISCUSSION

Widespread non-severe thunderstorms are expected throughout Central and Eastern Ontario along with the Golden Horseshoe on Friday. The highest concentration of storms is expected to be in Eastern Ontario along the St. Lawrence River although we may see some isolated storms further west around the GTA and Central Ontario.

The current model data suggest that the environment is quite favourable for the development of funnel clouds with these storms during the afternoon and evening. While funnel clouds don’t usually pose a threat, they could touch down and become a landspout tornado.

Landspout: A landspout is a type of tornado that forms under a weak thunderstorm. Unlike traditional tornadoes, which develop from supercell thunderstorms and are associated with a rotating updraft called a mesocyclone, landspouts form from non-supercell storms and do not have a mesocyclone. These tornadoes are generally weaker and shorter-lived than their supercell counterparts but can still pose a threat to property and life, with wind speeds occasionally reaching up to 160 km/h.