Ontario's weather is looking chaotic with frost, storms and a major blast of heat this week

The weather in Ontario is really throwing everything at us this week. From thunderstorms and frost warnings to a sudden heatwave, you'll definitely want to stay alert for what's coming.

According to The Weather Network, Ontario is in for some wild swings. It all kicks off with rounds of frost warnings, rain and the risk of thunderstorms on Monday, followed by a "second breath of summer" later in the week.

Here's everything you need to know about Ontario's weather forecast for September 9 to 13.

Monday a soggy mess with thunderstorms in the mix

Don't leave the house without your umbrella! Monday's weather is set to be a downpour-filled day for much of southern Ontario, with scattered thunderstorms and nickel-sized hail possibly adding some extra drama, according to Environment Canada. If you're commuting from the east along the 401 or 407, or from the north down the 400 or 404, expect delays and watch out for ponding on the roads.

Some areas could see up to 30 millimetres of rain, especially in the northern and eastern GTA. But in true unpredictable fashion, others (looking at you, Hamilton!) may only see a sprinkle. Lightning and gusty winds are possible, so keep your eyes on the forecast if you're out and about.

Frost advisories for northern & eastern Ontario

It's not just rain to watch out for on Monday. Environment Canada has issued a frost advisory for several regions in northern and eastern Ontario, including as far south as Pembroke, Barry's Bay and Renfrew, stretching north up to North Bay, Timmins and beyond.

With temperatures expected to drop near the freezing mark overnight Monday and into Tuesday morning, frost could pose a risk to crops and plants in frost-prone areas.

If you're in one of the affected regions, be sure to cover up your plants and garden veggies tonight to protect them from potential damage.

Summer makes a comeback by midweek

While Monday and Tuesday's weather might be a washout, the middle of the week brings a totally different vibe. Summer isn't quite done with us yet! A ridge of high pressure is building up and bringing back the warm temps we've been missing.

Expect highs in the mid to upper 20s across the province starting Wednesday, with some areas even reaching the 30s. This sunny stretch could last through next weekend, giving you a perfect excuse to break out the summer clothes again.

So between getting soaked in Monday's storms, bracing for frost, or soaking up the sun by Wednesday, it's going to be a week to remember. Stay safe, stay cool, and maybe keep that umbrella handy just in case!

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