The week ahead will have temps well above normal to start the week—and well below normal by the end of the week. 

Our stretch of summer-like weather continues today around Chicago and into the first several days of October. Normal high temps are in the upper 60s for the first part of this month. 

Wednesday looks to be the transition day towards soggier weather. Timing-wise, I think we’ll still end up in the low 80s but clouds fill our skies by the afternoon and some late-day showers/t’storms are possible.

Blustery and cooler with temps back towards normal on Thursday along with some rain and possible iso. t’storms. Lingering showers on Friday and it could be the start of a some much cooler than normal temperatures. If we end up hitting only 59 degrees– it’ll be our coolest afternoon since May 3rd. 

WGN weekly climate report: Hellooooo October! The tenth month of the year for Chicagoland comes with many many changes. We’ll get those in a moment—but first we’ll look back at September. 

The 9th month of the year in 2023 had more warm days than any other category. But we’ll likely remember it for the amount of cloud cover we had overall— and number of soggy days with more than half having at least 0.01″ of precipitation. Typically the whole month of September has about 65% of possible sun. September of 2023’s number will probably end up in the lower 50s when final numbers are tallied on Monday. 

The hottest days were a three-peat of 94 degrees on the 3rd to 5th. Our coolest morning was 53 on the the mornings of the 14th and 18th. With a tad more than three and a half inches of rain– we did catch up on our some of our summer drought conditions. 

In fact, we’re starting the month of October with many of us under no drought condition at all. Some abnormally dry and moderate drought conditions in NW Indiana and northwestern Chicagoland do persist. The drought conditions in other areas around the Great Plains are much worse to our west. 

For the month ahead– the average high temperature drops from 69 degrees today to 56 degrees by the last day of the month. The average low temperature goes from 51 today to 40 degrees by Halloween. This is largely due to the loss of 80 minutes of daylight over the next 31 days, the lower sun angle, and a typically wavy jet stream that can bring not only some heat but some colder weather outbreaks too. 

While many Octobers in Chicago have zero snow– we typically see 0.2″ of snow that happens by the last day of the month. Most of October precipitation is rain. An average October has 3.80″ of rain. Our wettest happened in 1954 with 12.06″ of rain. Our driest happened in 1897 with 0.18″ of precip. Some of you might remember our snowiest October happened in 1989 when we had 6.3″ of snow.  Our second snowiest October in more than 150 years of records happened in 2019 with 4.6″ of snow.