A Colorado low will bring a decent round of rain to Ontario through the early part of this week. A rainfall warning and special weather statements are in place for the southwest and Niagara region. Gusty winds and widespread amounts of 30-50 mm are expected in the southwest through Tuesday. A more detailed look at the week ahead, below.
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MONDAY AND TUESDAY: PROLONGED PERIOD OF RAIN, GUSTY WINDS
Environment and Climate Change Canada (ECCC) has issued a rainfall warning for the Windsor-Essex-Chatham-Kent region, with special weather statements elsewhere in the region, extending into the Niagara region due to the incoming rainfall.
The rain will ramp up Monday morning and linger through Tuesday before finally subsiding as the system treks stateside.
Considerable amounts of rainfall are expected, particularly in the southwest, through Tuesday evening. 30-50 mm is expected across the aforementioned region, with up to 50 mm possible in the Windsor area. 20-40 mm is anticipated for areas in the GTA and along the eastern shores of Lake Ontario, extending into Ottawa and Cornwall.
"Heavy downpours can cause flash floods and water pooling on roads. If visibility is reduced while driving, turn on your lights and maintain a safe following distance. Localized flooding in low-lying areas is possible," ECCC said in the rainfall warning.
The stubborn lake-effect showers will continue to plague areas east of Georgian Bay, so they won't escape the unsettled weather despite surrounding areas not being impacted by the Colorado low.
Strong wind gusts could reach 30-50 km/h by Monday morning. Areas near Lake Huron, Georgian Bay, and parts of the GTA could see gusts hit 60 km/h in the afternoon and evening.
Temperatures will drop in parts of the province, particularly in cottage country and eastern areas, where they will remain stuck in the single digits —falling a few degrees from Sunday.
LOOK AHEAD: SHORT-LIVED DRY PERIOD BEFORE NEXT BOUT OF RAIN, BRIEF WARM-UP
Beyond Monday, showers will linger through mid-week as the system will hold over the Eastern Seaboard.
Southern Ontario will then get a brief break with fair weather and milder temperatures ahead of the next Colorado Low, which will track into the Great Lakes region late next week. It will be a slow-moving system bringing periods of rain, windy conditions, and mild temperatures.
Forecasters are watching for a significant shot of chilly weather around Halloween or for the start of November.
Be sure to check back for the latest updates across Ontario.