Oak leaves in autumn. © Can Stock Photo / pstedrakOak leaves in autumn. © Can Stock Photo / pstedrak
Sarnia

Sudden drops in temperature anticipated this fall

Despite the recent warm weather across southwestern Ontario, the start of autumn will bring fluctuating temperatures and longer storm systems to the region.

The fall equinox arrives at 9:04 p.m. on Thursday, September 22.

The temperature dropped from a high of 28 C, 82 F with a humidex of 37 C, 99 F on Wednesday, to a forecasted high of 16 C, 61 F on Thursday.

Environment Canada Meteorologist Gerald Cheng said residents "will need to get used to" big temperature changes this season.

"Our temperatures will be in the teens, maybe getting up to the 20-degree mark. Twenty-one degrees is really our seasonal high for this time of year but it will be very unlikely that we will see 30 degrees in the next two weeks," said Cheng. "Also, because of the season, this is the transition from summer to winter, we will see a lot of fluctuations in temperatures."

In terms of precipitation, Cheng said there are some indications that it will be drier than normal this fall but that could change.

"I wouldn't hold on to this forecast too tightly because there still is that chance where it's going to be near normal and even above. The signal isn't really strong," said Cheng. "We know that with precipitation, it can be highly variable."

During this transition in seasons, Cheng said big low-pressure systems could cause longer storm systems where some regions see a full day of rain or even snow.

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