Right now in Chula Vista, the air is about 80°F, but the model estimates the asphalt under your dog's paws is closer to 123°F — a gap of roughly 43°F, because clear skies are pouring full sun onto every dark surface. That reading puts Chula Vista in the caution range, where short, shade-hugging walks are the most a paw should take. Humidity is nudging the human "feels-like" to about 84°F, which matters for your dog too: muggy air makes it harder for a panting dog to shed heat, so treat a borderline reading as the hotter of the two.
Across the 12 hours left today, the pavement in Chula Vista is projected to top out near 131°F around 1 PM, when the air will be about 81°F — a 50°F gap between the forecast your weather app shows and the surface your dog walks on. The surface is still gaining — up about 3°F over the next three hours — so a walk taken now is cooler than the same walk later this afternoon.
In an average August, Chula Vista sees highs around 78°F and overnight lows near 66°F. Those are forgiving numbers, but don't let them lull you — a sunny, still afternoon can still heat dark asphalt far above the air, especially for low-riding or short-coated dogs. As a seasonal rule of thumb, the safest windows are before about 11:00 AM and after about 4:00 PM.
Chula Vista loses its all-day safe window in 5 months of the year — May through September — and August is one of them. The year peaks in September at an average high of 78°F against 63°F in March, a 15°F swing that decides how much of the day belongs to your dog.
Chula Vista sits about 7 miles from San Diego, close enough that the two usually run within a degree or two of each other — if your walk crosses between them, either page answers the question. Street-level conditions still differ more than city-level ones do: a shaded side street and an open parking lot half a block apart can be twenty degrees apart underfoot.
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 Chula Vista, 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.