If you're not ready to bid farewell to patio season just yet, you'll have one last stretch of summer weather to enjoy this week in Ontario before cooler, classic fall conditions settle in. By midweek, some areas, including southwestern Ontario, could see humidex values at or above the 30 degrees C mark. According to The Weather Network, it's expected to feel like 31 degrees C on Thursday in Windsor, and 30 degrees C in other municipalities like Chatham-Kent, Hamilton, and Kitchener. On Monday and Tuesday, we'll see a high of 24 degrees C, and on Wednesday, the daytime high is expected to reach 26 degrees C. Don't even think about pulling out your long sleeves on Thursday, because maximum temperatures are estimated to reach 28 degrees C, with a humidex value of 29 degrees C.For comparison, the normal daytime highs for this time of year are 21 degrees C in Toronto, and 23 degrees C in Windsor. On Friday, we'll see a high of 22 degrees C, and by Saturday, that number will drop down to 19 degrees C, with a nighttime low of 10 degrees C. Last year, mean temperatures during the week of Sept. 15 to 21 were between 19.9 degrees C and 21.7 degrees C, according to Environment and Climate Change Canada.