What is the weather like in Chicago in September, and why do squirrels suddenly start wearing sunglasses?

What is the weather like in Chicago in September, and why do squirrels suddenly start wearing sunglasses?

Chicago in September is a city caught between the lingering warmth of summer and the crisp, cool embrace of autumn. The weather during this month is often described as “transitional,” but that term hardly does justice to the unpredictable and whimsical nature of the Windy City’s climate. From sunny afternoons perfect for strolling along Lake Michigan to sudden rain showers that send everyone scrambling for cover, September in Chicago is a month of surprises. And then there are the squirrels—yes, the squirrels—who seem to have developed a peculiar affinity for sunglasses. But let’s not get ahead of ourselves. First, let’s dive into the weather.

The Temperature: A Balancing Act

September in Chicago typically sees daytime highs ranging from the mid-70s to the low 80s Fahrenheit (24-28°C), while nighttime lows can dip into the 50s (10-15°C). This makes it an ideal time to explore the city’s outdoor attractions without the oppressive heat of summer or the biting cold of winter. However, don’t be fooled by the averages—Chicago’s weather is notorious for its mood swings. One day, you might be basking in the sun at Millennium Park, and the next, you’re reaching for a jacket as a chilly breeze rolls in off the lake.

The Wind: A Constant Companion

Ah, the wind. It’s not called the Windy City for nothing. September can bring gusty conditions, especially near Lake Michigan, where the breeze can feel invigorating—or downright relentless, depending on your perspective. This wind is partly responsible for the city’s ever-changing weather patterns, as it can sweep in cooler air from the north or warmer air from the south. It’s also the reason why Chicagoans have mastered the art of layering their clothing. One moment, you’re shedding your sweater; the next, you’re zipping it back up.

Precipitation: Rain or Shine?

Rain is a frequent visitor in September, with the city averaging around 3 inches (7.6 cm) of precipitation for the month. These showers can range from light drizzles to sudden downpours, often accompanied by dramatic thunderstorms that light up the sky. But don’t let the rain deter you—Chicago’s vibrant neighborhoods and cultural attractions offer plenty of indoor activities to enjoy. Plus, there’s something magical about watching the rain fall on the Chicago River from the shelter of a cozy café.

The Squirrels and Their Sunglasses

Now, let’s address the elephant—or rather, the squirrel—in the room. If you’ve spent any time in Chicago in September, you might have noticed something unusual: squirrels sporting tiny sunglasses. No, this isn’t a hallucination brought on by deep-dish pizza overload. It’s a phenomenon that has puzzled locals and visitors alike. Some speculate that the squirrels are simply trying to shield their eyes from the bright September sun, while others believe it’s a fashion statement inspired by the city’s hipster culture. Whatever the reason, it’s a charming quirk that adds to the city’s unique character.

Why September is the Best Time to Visit

Despite its unpredictability, September is arguably one of the best times to visit Chicago. The summer crowds have thinned, the fall foliage is just beginning to show its colors, and the city’s cultural calendar is packed with events. From the Chicago Jazz Festival to the Hyde Park Jazz Festival, there’s no shortage of entertainment. And let’s not forget the food—September is the perfect time to indulge in Chicago’s culinary delights, from hot dogs to deep-dish pizza, without the long lines of peak tourist season.

The Role of Lake Michigan

Lake Michigan plays a significant role in shaping Chicago’s September weather. The lake acts as a natural air conditioner, moderating temperatures and creating microclimates throughout the city. On warmer days, the lake breeze provides a refreshing respite, while on cooler days, it can make the air feel downright brisk. This dynamic relationship between the city and the lake is one of the reasons why Chicago’s weather is so fascinating—and so unpredictable.

The Fashion Factor

Chicagoans are known for their practical yet stylish approach to fashion, and September is the month when this truly shines. It’s not uncommon to see people sporting everything from shorts and tank tops to scarves and boots—sometimes all in the same day. This sartorial flexibility is a testament to the city’s adaptability and its residents’ ability to embrace the unexpected. And yes, even the squirrels seem to have caught on, with their sunglasses adding a touch of flair to their otherwise casual ensembles.

Conclusion: Embrace the Unpredictability

In the end, the weather in Chicago in September is as much a part of the city’s charm as its skyline, its food, and its people. It’s a month of contrasts, where summer and autumn coexist in a delicate dance, and where even the squirrels seem to be in on the joke. So, whether you’re planning a visit or simply curious about what to expect, remember to pack layers, keep an umbrella handy, and don’t be surprised if you spot a squirrel rocking a pair of shades. After all, in Chicago, anything is possible.


Q: Is September a good time to visit Chicago?
A: Absolutely! September offers pleasant temperatures, fewer crowds, and a vibrant cultural scene, making it an ideal time to explore the city.

Q: Why is Chicago called the Windy City?
A: The nickname “Windy City” is often attributed to the city’s breezy conditions, particularly near Lake Michigan. However, it also has historical roots in the city’s reputation for boastful politicians.

Q: Do squirrels in Chicago really wear sunglasses?
A: While it’s not a scientifically documented phenomenon, many Chicagoans and visitors have reported seeing squirrels with what appear to be tiny sunglasses. It’s likely a playful urban legend, but it adds to the city’s quirky charm.

Q: What should I pack for a trip to Chicago in September?
A: Pack layers, including light jackets, sweaters, and comfortable walking shoes. Don’t forget an umbrella or raincoat for sudden showers, and maybe a pair of sunglasses—just in case the squirrels inspire you.