Rare August Frost Risk for Parts of Southern Ontario on Wednesday Night

/

NOTE: YOU CAN CLICK ON THE MAP TO OPEN A ZOOMABLE IMAGE WHICH WILL BE EASIER TO READ.

As August gives way to September, there is usually a noticeable fall-like feeling in the air, marked by the gradual transition from warm, humid summer temperatures to crisp autumn temperatures. This seasonal shift generally unfolds over weeks, with overnight lows gradually settling into the mid to upper single digits. Eventually, the risk of frost sneaks into the conversation, typically by late September or early October, depending on the region.

This year, however, Mother Nature seems inclined to speed up this transition with a preview of fall weather for Southern Ontario over the next few days. Currently, daytime highs for Wednesday are hovering in the low to mid double digits for much of the region leading to a chilly feeling in the air.

This is just the beginning of the 'August Freeze.' We are expecting a chilly start to the day on Thursday, with overnight temperature lows plummeting to 5-10°C across much of Southern Ontario. The colder air will encompass much of Southern Ontario with the warmest temperatures being found in Deep Southwestern Ontario and around Lake Ontario.

On the other hand, in some higher elevation areas of Central Ontario, like Muskoka, Haliburton, and Algonquin Park, the temperature might drop to near the freezing mark. Because of this and clear skies, there could be the risk of frost during the overnight hours extending into the early morning of Thursday. This is unusual for this time of year, as Algonquin Park usually experiences its first frost on September 22nd.

As a result, Environment Canada has issued a frost advisory for the following locations:

  • Baysville

  • Burk's Falls

  • Deep River

  • Eastern Algonquin Park

  • Fort Irwin

  • Huntsville

  • Lake of Two Rivers

  • Northern Haliburton County

  • Oxtongue Lake

  • South River

  • Western Algonquin Park

  • Whitney

Environment Canada mentions the potential for frost to develop late tonight and continuing into the pre-dawn hours of Thursday:

For the summer lovers, don’t worry as this taste of autumn will be brief. We will see the return of more seasonal temperatures by the weekend. The start of a new week and September's first full week could feature daytime highs soaring well into the 30s for some areas. There will also be the risk of thunderstorm activity!