Right now in Modesto, the air is about 64°F, but the model estimates the asphalt under your dog's paws is closer to 64°F — the surface and air have nearly converged because a mix of sun and cloud is still loading heat into the asphalt. That reading puts Modesto in the clear for an ordinary walk. Air temperature alone would have told you none of this — the pavement, not the forecast, is what your dog actually stands on.
Across the 17 hours left today, the pavement in Modesto is projected to top out near 135°F around 2 PM, when the air will be about 94°F — a 42°F gap between the forecast your weather app shows and the surface your dog walks on. Today breaks into 2 separate safe stretches rather than one continuous window, so missing the first does not cost you the day.
In an average August, Modesto sees highs around 100°F and overnight lows near 66°F. At highs like that, sun-baked pavement can easily top 120–130°F by early afternoon, so the walkable hours cluster around dawn and after sunset. As a seasonal rule of thumb, the safest windows are before about 9:00 AM and after about 6:00 PM.
Modesto loses its all-day safe window in 6 months of the year — April through September — and August is one of them. The year peaks in July at an average high of 101°F against 57°F in December, a 44°F swing that decides how much of the day belongs to your dog.
The nearest place we track is Stockton, about 27 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 Modesto'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. Conditions in Modesto are on the gentler side right now, but keep the same habits: water before and after, grass over asphalt, and a close eye on flat-faced breeds, seniors, and puppies, who overheat and burn sooner than a healthy adult dog.