Right now in Irvine, the air is about 92°F, but the model estimates the asphalt under your dog's paws is closer to 144°F — a gap of roughly 52°F, because clear skies are pouring full sun onto every dark surface. That reading puts Irvine in the danger range, where pavement can scald paw pads in under a minute. Air temperature alone would have told you none of this — the pavement, not the forecast, is what your dog actually stands on.
Across the 11 hours left today, the pavement in Irvine is projected to top out near 144°F around 2 PM, when the air will be about 93°F — a 52°F gap between the forecast your weather app shows and the surface your dog walks on. The surface is already coming down, about 17°F over the next three hours, so waiting a little works in your favour here.
In an average August, Irvine sees highs around 83°F and overnight lows near 64°F. Even at those moderate highs, a dark surface in direct sun can run 40–60°F hotter than the air, which is enough to tip midday walks into the caution range. As a seasonal rule of thumb, the safest windows are before about 10:00 AM and after about 5:00 PM.
Irvine 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 August at an average high of 83°F against 64°F in January, a 18°F swing that decides how much of the day belongs to your dog.
Irvine sits about 6 miles from Costa Mesa, 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 Irvine, 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.