Asphalt vs. air temperature: what our field readings show
How much hotter is asphalt than the air temperature? We measured real surfaces coast to coast with an infrared thermometer. Here is what pavement actually reads.
Weather apps report air temperature. Dogs walk barefoot on surfaces. To quantify the difference between those two realities, we spent months taking infrared thermometer readings of real sidewalks, streets, trails, and parks: coast to coast, across urban, suburban, and rural settings. Asphalt, concrete, and grass: the surfaces dogs actually walk on.
That dataset is what Pawcast is built on. Here is what it shows.
How much hotter does asphalt get than the air?
Pavement in full sun does not match the air temperature. It runs far hotter, and can stay hot even after the day starts to cool.
One note on scope: this post focuses on heat, because summer is the season underway. The same field kit collected cold-weather readings too: frozen ground, wind, salt season. We will put that data to work as the seasons turn.
Representative reading from our dataset: asphalt at 125°F under an 87°F air temperature. A 38-degree gap, invisible on any weather app.
Not all surfaces behave alike
Averaged across comparable sun conditions, the pattern in our data is consistent:
- Asphalt absorbs the most and holds it longest. It is routinely the hottest surface on a route.
- Concrete runs cooler than asphalt in identical sun, but still substantially above air temperature at midday.
- Grass stays closest to air temperature and sheds heat fastest when clouds pass.
- Artificial turf deserves special mention: it can spike aggressively in direct sun despite feeling like a "park" surface. If your dog park uses it, treat it like pavement until you have checked it.
Shade changes everything
The same asphalt, sun versus shade, produced some of the largest single-variable swings in our dataset. This is why Pawcast displays sun and shade surface values separately rather than blending them into one average: an average hides the extreme, and the extreme is what burns paws.
How hot is too hot for a dog's paws?
The scientific literature tells us that just 60 seconds at 120°F can cause skin damage (Wohlsein et al, Vet Path. 2016). Our field data shows ordinary summer pavement crossing that line regularly, and in cities you would not call extreme.
What we do with this
All of this data feeds Pawcast. You get one number for your dog and your conditions, without doing any advanced math yourself. It is the difference between a forecast and a Pawcast.
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See it for your street
The gap in this post is not an abstraction: it is happening on your block right now. Create a free account and add your dog to see today's reading for your conditions.
Create your free accountHow Pawcast talks about conditions
A note on the words you will see in this post and in the app. Pawcast™ (weather.pet) describes conditions using three tiers: WITHIN RANGE, CAUTION, and HIGH RISK, alongside a Dog Feel° temperature and a Risk Score from 0 to 100. Conditions are also described relative to your dog's personal band: BELOW RANGE, WITHIN RANGE, or ABOVE RANGE. You will not see absolute promises in Pawcast, in either direction: no wording that guarantees a walk will go well, and no wording that a given moment is risk-free. Conditions are always relative to your specific dog, and your judgment on the ground always comes first.
Educational content, not veterinary advice. This article is for general informational purposes only and is not a substitute for professional veterinary advice, diagnosis, or treatment. Every dog is different: breed, age, weight, and health conditions all change what a given day demands. Always consult your veterinarian with questions about your dog's health, and contact a veterinarian immediately if you believe your dog is experiencing a medical emergency. Pawcast's tiers, Dog Feel°, and Risk Score are informational planning tools, not medical guidance.