Southern Ontario's weekend warm-up to come with a thundering price
Parts of southern Ontario are under a special weather statement for the potential for heavy rain this weekend. There's also the risk of thunderstorms and localized flooding as temperatures climb
A taste of early spring will spread across southern Ontario this weekend, with temperatures even nearing the 20-degree mark for the first time this year in parts of the southwest.
With the warmth however, comes a rainy catch, as a powerful Colorado low spans much of central and eastern North America.
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The storm will bring a wintry mess to Manitoba and northwestern Ontario, while heavy rain and even thunderstorms threaten parts of southern Ontario as a second low follows quickly into Sunday.
With a risk of thunderstorms, localized flooding is possible with heavier rain totals, especially since the frozen ground has a reduced ability to absorb this rainfall.
This weekend: Surge of mild air brings heavy rain threat with it
A line of non-severe thunderstorms entered southwestern Ontario early Saturday morning, and will continue to move eastward, bringing the risk of lightning, heavy downpours, and small hail to the rest of southern Ontario. London's airport reported thunderstorm conditions shortly before 8 a.m. ET.
As the line of thunderstorms moves east towards the Greater Toronto Area (GTA), the storms will start to disorganize and dissipate, becoming much lighter and scattered for the GTA through the early afternoon.
Strong southerly wind gusts are expected on Saturday afternoon in southwestern Ontario.
As the Colorado low tracks north, a secondary low will form along the trailing cold front, which will bring in more widespread rain Saturday overnight, and through the day on Sunday.
Localized flood threat with heavy rain, snowmelt, and thunderstorms
Embedded thunderstorms are possible throughout all of southern Ontario Sunday, and could even push into sections of the northeast, as well.
This rain will move into eastern Ontario midday Sunday, and continue through the day and into the overnight hours, before easing Monday morning.
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A widespread 10-20 mm of rain is forecast through the weekend, with locally higher amounts up to 40 mm across the southwest and into the Nickel Belt region.
The rain and milder temperatures will cause additional snowmelt, with the threat for localized flooding, and water pooling on roadways. There's also a risk for ice jams on creeks and rivers.
"The frozen ground has a reduced ability to absorb this rainfall," says Environment and Climate Change Canada (ECCC) in the special weather statement issued early Friday morning.
Another Colorado low is expected next week, but this storm is not expected to be nearly as strong as the impending system. However, it should also have more cold air to work with and bring snow to parts of Eastern Canada.
Stay with The Weather Network for your latest forecast across Ontario.