Thursday, August 13th 2020, 10:19 am - Southern Ontario could be in for an unsettled or dry weekend, depending on the timing of a stateside upper-level low.
A somewhat complex setup in the upper levels of the atmosphere is taking hold, posing a problem for southern Ontario's forecast for this weekend with some uncertainty regarding the timing of an upper-level low that is south of the border. The issue is the speed at which it advances into the region, which could make for an unsettled or dry forecast Saturday and Sunday. A deeper look at the scenarios that could play out, and what's beyond, below.
- Uncertain forecast Saturday with timing of upper-level low, could be wet and stormy or dry and sunny
- Sunday will feature at least a passing shower, with cooler temperatures
- Early taste of fall next week
- Keep on top of severe weather ALERTS in your area
POSSIBLE WEEKEND SCENARIOS
One of the systems heading toward southern Ontario is an upper-level trough in the northwestern region, which will slowly swing southward with a cold front. The other is a weaker upper-level low that is currently stateside. The uncertainty lies in the speed of which the latter system makes it into the south.
The first forecast model indicates the upper-level low will be a little slower in tracking towards the region, which would keep the majority of the weekend dry.
However, more recent models have trended towards the system heading to southern Ontario a little bit quicker, prompting the chance of showers and thunderstorms for Saturday afternoon. It's not a guarantee just yet, but it's a situation we will closely monitor as we approach the weekend. The good news is, if this scenario plays out, temperatures will be seasonably warm.
There is more certainty with Sunday's forecast, with the expectation of at least a passing shower. It's too early to determine how much rain will fall, but like Saturday, it's a forecast we will be keeping a close eye on as head into the weekend.
Temperatures will be cooler on Sunday, with daytime highs dropping several degrees in some southern Ontario locales.
LOOK AHEAD: HIGHER CHANCE OF RAIN INTO EARLY NEXT WEEK, EARLY TASTE OF FALL
The greatest chance for rain and thunderstorms in southern Ontario will be Sunday night into Monday, as the cold front slowly tracks into the region.
Behind the front, the region will have a taste of early fall for a few days, with another cold front possibly tracking into southern Ontario late next weekend.
"However, summer is by no means over for Ontario and Quebec. A warmer pattern is expected to return as we head towards the final days of August, and September should bring an abundance of summer weather to this region," said Weather Network meteorologist Dr. Doug Gillham.
Keep an eye on the forecast as we continue to monitor Ontario's weather outlook.