Right now in Chicago, the air is about 86°F, but the model estimates the asphalt under your dog's paws is closer to 117°F — a gap of roughly 31°F, because clear skies are pouring full sun onto every dark surface. That reading puts Chicago in the caution range, where short, shade-hugging walks are the most a paw should take. Air temperature alone would have told you none of this — the pavement, not the forecast, is what your dog actually stands on.
Across the 10 hours left today, the pavement in Chicago is projected to top out near 117°F around 2 PM, when the air will be about 86°F — a 31°F gap between the forecast your weather app shows and the surface your dog walks on. The surface is already coming down, about 20°F over the next three hours, so waiting a little works in your favour here.
In an average October, Chicago sees highs around 62°F and overnight lows near 48°F. That keeps most of the day walkable, though a rare clear, calm afternoon can still warm exposed pavement more than the mild air suggests. For this month the normals suggest pavement rarely reaches unsafe temperatures here, but the seven-second hand test is still the final word on any given day.
Chicago loses its all-day safe window in 3 months of the year — June through August — and October is not one of them. The year peaks in July at an average high of 81°F against 32°F in January, a 49°F swing that decides how much of the day belongs to your dog.
The nearest place we track is Naperville, about 26 miles away. That is close enough to move together in a heat wave but far enough that a passing cloud bank or a coastal breeze can put real distance between the two readings, so check Chicago's own page rather than assuming.
Whatever the number says, confirm it with your hand: press the back of it flat on the pavement for seven seconds. If you can't hold it there, neither can your dog. On a day reading this warm in Chicago, flat-faced breeds like pugs and bulldogs, plus seniors and young puppies with thinner pads, should sit out the heat entirely — subtract about 10°F from any safe threshold for them. If you must cross hot ground, protective booties or a quick coat of paw wax are the only real barrier between paw pads and the asphalt.