Dog Surfing: How to Get Started This Summer
Which Dogs Shouldn't Hike in Summer Heat
Not all dogs are experiencing 85°F the same way. That’s what gets lost when heat safety advice treats every dog as a single category.
A 2020 study published in Scientific Reports analyzed heatstroke cases across nearly a million dogs under veterinary care in the UK and found Chow Chows had 17 times the heatstroke incidence of Labrador Retrievers under the same environmental conditions. Same temperature. Same humidity. Same outdoor exposure. Completely different risk profile. The researchers identified breed as one of the strongest predictors of heatstroke, alongside brachycephalic conformation and elevated body weight.
Seventeen times is not a rounding error. That’s a Chow Chow and a Lab occupying different risk universes at identical temperatures.
Most heat safety content, including most of what’s on this site, gives you solid general guidance: start at dawn, watch the combined temp-humidity index, read the early warning signs, carry more water than you think you need. All of that remains true for every dog. But none of it accounts for whether your dog is a Vizsla built for hunting in the warm Hungarian plains or a Bulldog with an airway that can’t keep up with a brisk walk in July. Those aren’t the same conversation.
This post maps breed types to real temperature thresholds, explains the anatomy driving those differences, and gives you a framework for deciding whether your specific dog should be on summer trails at all.
Quick Reference: Breed Heat Tolerance by Type
Breed Category Examples General Temp Limit Heat Risk Brachycephalic Bulldog, Pug, French Bulldog, Boston Terrier, Boxer ~65–75°F Extreme Heavy double-coated northern Husky, Malamute, Samoyed, Chow Chow ~70–75°F Very High Large/heavy single-coated Bernese Mountain Dog, St. Bernard, Newfoundland ~75°F High Standard mixed/working breeds Lab, Golden, Border Collie, Shepherd mixes ~82–85°F Moderate Lean warm-climate athletic breeds Vizsla, Rhodesian Ridgeback, GSP, Weimaraner ~88–90°F Lower Temp limits are air temperature at trail level during sustained exertion, not forecast high. Senior dogs and overweight dogs shift their category one level higher in risk regardless of breed. These are practical thresholds, not clinical standards, based on breed physiology and published heatstroke research.
Brachycephalic Breeds: A Lower Risk Window Than You’d Expect
What dogs are brachycephalic?
Brachycephalic (flat-faced) dog breeds are dogs with shortened skull structure that compresses the nasal passages and airway (primarily English Bulldogs, French Bulldogs, Pugs, Boston Terriers, Boxers, and Shih Tzus). They are at extreme risk of heatstroke during physical activity because their shortened airways make panting (the primary canine cooling mechanism) significantly less efficient than in dogs with normal anatomy.
Panting is how dogs dump heat. Evaporation across a long, moist nasal passage and airway surface is the engine. A Labrador’s nasal passage gives that process 4 to 6 centimeters of evaporative surface on each breath cycle. A Bulldog’s compressed airway gives it a fraction of that. More breaths per minute, less cooling per breath, more effort expended in the attempt.
The consequence: brachycephalic breeds begin showing heat stress symptoms at air temperatures that most other dogs would handle with moderate management. That threshold can be somewhere in the 65 to 75°F range during sustained exertion — depending on humidity, sun exposure, and individual dog factors. Not 85°F, not 90°F. As low as sixty-five degrees. On a shaded trail with a light breeze at 10 AM in May.
This isn’t a conservative estimate. Published research on brachycephalic dogs has consistently found these breeds are overrepresented in heatstroke cases at ambient temperatures that would be considered benign for typical dogs.
What this means for summer hiking: A Bulldog, Pug, or French Bulldog’s summer hiking window is earlier, shorter, and more constrained than you’d expect. A 5 AM start that’s fine for a healthy Lab on an 85°F forecast day might not be safe for a Bulldog on an 82°F forecast day, depending on the route exposure and humidity. The combined temp-humidity index approach applies, but their functional threshold is around 130 — not 150 — meaning the math turns bad faster.
The honest answer for some brachycephalic dogs in summer: trails aren’t it. Short shaded walks in the early morning, yes. A 4-mile round trip with elevation gain in June, probably not.
Northern Double-Coated Breeds: Built for Cold, Not Summer Trails
Huskies, Alaskan Malamutes, Samoyeds, Akitas — these dogs were engineered for arctic conditions. Dense undercoat, guard hairs, the whole insulation system that keeps a working sled dog comfortable at −40°F. In summer, that same system works against them.
Double-coated breeds can maintain acceptable core temperature longer during short exertion, but they accumulate heat rapidly under sustained effort and struggle to dump it through panting alone. The insulation that protects from cold works both directions — it holds body heat in when the dog needs to shed it.
Their general safe threshold for sustained trail exertion lands around 70 to 75°F air temperature, with close monitoring required even below that on humid days or exposed terrain.
The shaving myth
Here is the part that causes real harm every summer: double-coated breeds should not be shaved for summer.
The double coat on a Husky or Malamute does more than trap warmth. The outer guard hairs block solar radiation — direct absorption from sunlight — that a single-coated or shaved dog would absorb into the skin. The undercoat creates an insulating air layer that slows heat transfer from the environment into the body. Shaving removes both of those protective functions. A freshly shaved Husky has more solar radiation reaching its skin, less insulating air buffer, and is more exposed — not less — to heat load in direct sun.
There’s also a documented grooming complication called post-clipping alopecia, where the coat fails to regrow correctly after shaving in double-coated breeds, potentially leaving them permanently compromised. The AKC addresses this directly in its guidance against shaving double-coated breeds for warm weather.
The right approach for summer with a double-coated breed: regular brushing and deshedding to remove the loose undercoat (which is the layer that blocks natural airflow), earlier start times, more frequent rest stops, and honest assessment of whether the planned route is appropriate given the breed’s thermal limitations.
Chow Chows specifically
The Scientific Reports study put the Chow Chow at 17 times the heatstroke risk of Labrador Retrievers. That number is partly the double coat and partly body structure — Chow Chows have a relatively broad, heavy build that generates more metabolic heat under exertion. The combination puts them at the upper end of summer risk even among double-coated breeds.
If you have a Chow Chow and you’re asking whether summer trail hiking is reasonable: be honest with yourself about the temperature. A 70°F morning with cloud cover is different from a 70°F morning with full sun and 60% humidity. The Chow Chow can’t tell you the difference. You have to account for it.
Large Heavy-Coated Breeds: High Risk, Often Underestimated
Bernese Mountain Dogs, Saint Bernards, Newfoundlands, and similar large, heavy-coated dogs don’t get the same press as Huskies for summer heat risk, but they’re genuinely high-risk.
Size amplifies heat risk for a physiological reason: larger body mass generates more metabolic heat per movement, but the surface-area-to-volume ratio decreases as body size grows. A Great Pyrenees has proportionally less body surface available for heat dissipation than a 35-pound dog, even though it’s generating far more heat. The cooling system doesn’t scale linearly with mass.
These breeds should be treated with similar caution to double-coated northern breeds — practical safe hiking temperatures around 75°F with sustained effort, and closer to 70°F in high humidity or full sun conditions.
Senior Berners and Newfoundlands are an especially vulnerable group. Both breeds already skew toward cardiac and joint issues with age, and cardiovascular efficiency affects heat tolerance directly. An 8-year-old Bernese Mountain Dog is not a summer hiking companion for exposed midday trails, period.
Standard Working and Sporting Breeds: The 85°F Benchmark
Labs, Goldens, German Shepherds, Border Collies, Australian Shepherds, most sporting dog mixes — this is the group for whom the standard 85°F threshold was built.
These are athletic dogs with normal airway anatomy, single or moderate coats, and reasonably efficient thermoregulation. They can handle summer hiking with solid heat management: dawn starts, abundant water, gum color checks, the early warning sign protocol, appropriate timing cutoffs.
This is also the category where complacency is most dangerous. Because Labs and Goldens are the default “hiking dog” in most people’s heads, they’re the breed most likely to end up on a 10 AM trail in 88°F heat with an owner who figured the dog would be fine. They’re manageable in heat with proper management. They’re not heat-proof.
Golden Retrievers are worth a specific note: the double-layer coat (dense undercoat plus water-resistant outer coat) means summer heat load is meaningfully higher than for a single-coated dog of the same size. A Golden in peak winter coat heading into May heat deserves closer monitoring than a Lab with a similar athletic profile.
The summer hiking timing framework was written primarily for this group. Healthy adult mixed breeds and working dogs, managed properly, with dawn starts and proper monitoring, can continue enjoying trails through summer. The framework specifies their exit times by forecast temperature.
Lean Warm-Climate Athletic Breeds: Higher Baseline Tolerance
Vizslas, Rhodesian Ridgebacks, German Shorthaired Pointers, Weimaraners, and similar breeds evolved for or were selectively developed in warmer climates for sustained athletic work in heat.
One notable exception worth flagging: Greyhounds. The lean, short-coated physique looks like it belongs in this category, and racing Greyhounds are sometimes considered heat-tolerant in that specific context. But the Hall et al. 2020 study found pet Greyhounds had 4.26x higher heatstroke odds than Labrador Retrievers — placing them firmly outside the low-risk group despite their build. If you have a pet Greyhound, treat it closer to the standard working breed category rather than the high-tolerance breeds listed here.
The anatomical advantages are clear. Short, single-layer coats that don’t trap heat. Lean builds with favorable surface-area-to-mass ratios for heat dissipation. Efficient cardiovascular systems conditioned for sustained output. Long nasal passages that maximize evaporative cooling per breath.
These breeds tolerate summer trail conditions that would be genuinely dangerous for the breed categories above. A conditioned Vizsla can handle a properly managed trail in moderate heat that would be a bad idea for a Golden. A Rhodesian Ridgeback will manage 86°F with early morning timing that would have put a Husky in danger at 72°F.
General guideline: lean, short-coated warm-climate breeds can extend the threshold to around 88 to 90°F with solid heat management — earlier start than the standard group, but more margin than the rest.
The caveats still apply: conditioning matters (an unconditioned Vizsla is not the same as a conditioned one), age matters (a 10-year-old GSP has less cardiovascular reserve than a 4-year-old), and the combined temp-humidity index can move any dog into risk territory faster than air temperature alone suggests. These breeds have better heat tolerance, not immunity.
Senior Dogs and Overweight Dogs: The Compounding Factor
Regardless of breed, two factors push any dog up the risk ladder: age and weight.
Older dogs (roughly 7 and up) experience declining cardiac efficiency and reduced thermoregulatory capacity. The same dog at age 9 that handled summer trails at age 4 is genuinely less heat-tolerant now — not a little less, measurably less. The breed’s baseline tolerance still applies, but their age shifts them toward the higher end of that breed’s risk range.
A 10-year-old Lab is not the same heat conversation as a 4-year-old Lab. Treat the older dog like a moderately more heat-sensitive version of their breed category.
Overweight dogs face compounding heat risk from two directions. Extra body mass generates more metabolic heat during exertion — same problem as the large breed issue above, scaled. Additionally, excess fat acts as insulation, reducing the body’s ability to shed that heat. An overweight dog at 75°F is effectively working in conditions 5 to 10 degrees more demanding than a lean dog of the same breed.
An overweight Bulldog in summer heat is occupying the most dangerous quadrant of this chart. Short, flat face. Elevated body mass. Compromised panting. Summer heat.
If your dog is carrying extra weight and summer hiking is on the agenda, the honest framework is: run their normal breed threshold down by at least 10°F and build conditioning first, before the hot months.
How to Know If Your Dog Should Skip Summer Trails
What temperature is too hot to hike with my dog?
The answer depends on breed type. For brachycephalic breeds, somewhere in the 65–75°F range during sustained trail effort is a practical limit — the exact threshold shifts with humidity, sun exposure, and individual conditioning, and some dogs show stress at the lower end of that range. For double-coated northern breeds like Huskies and Malamutes, 70 to 75°F with close monitoring. For standard working breeds (Labs, Goldens, Shepherds), 85°F is the threshold for sustained activity. For lean, short-coated warm-climate breeds, threshold extends to around 88 to 90°F with proper timing and monitoring. Senior and overweight dogs in any category shift to lower thresholds.
Here’s a three-question framework for your specific dog:
1. What’s the anatomical starting point? Flat-faced or heavy double-coated? You’re starting with a dog who faces a real disadvantage at temperatures most advice treats as fine.
2. What’s the modifying condition? Age over 7? Carrying extra weight? Coming out of a low-activity winter without conditioning? Each of these pushes the threshold lower. Two of them together pushes it significantly lower.
3. What’s the actual exposure? Not just air temperature — the combined temp-humidity index, route exposure (full sun vs. consistent shade), trail surface (rock versus dirt), elevation, and expected exertion level all affect real heat load.
A Pug at question 1, plus age 8 at question 2, plus full-sun exposed trail in July at question 3: that dog shouldn’t be on summer trails. That’s not excessive caution. That’s an honest read of what the dog can handle.
A conditioned 4-year-old GSP at question 1, lean and healthy at question 2, shaded forest trail at 5:30 AM at question 3: manage the timing, watch the signs, bring enough water. That’s summer hiking.
What to Watch For Regardless of Breed
Even the most heat-tolerant breeds need active monitoring. The full early-warning guide covers the signal system in detail. The quick version:
- Panting that doesn’t slow down during rest stops (normal panting settles within 2–3 minutes of shade; heat-stress panting stays elevated)
- Active shade-seeking that overrides trail interest
- Refusing high-value treats at rest stops (physiological, not behavioral)
- Gum color shift from bubblegum pink to bright red
For higher-risk breeds — brachycephalic, heavy double-coated, senior, overweight — run these checks every 15 to 20 minutes rather than every 30. The window between early signals and a genuine heatstroke emergency is shorter for these dogs.
A cooling vest (evaporative, not gel-pack) extends the margin before early signals start appearing — useful for the moderate-risk dogs, less useful as a substitute for trail avoidance for the extreme-risk ones. Paw burns from superheated rock surfaces are a secondary concern on hot days regardless of breed; the paw burn guide has the surface temperature data.
The underlying principle here is simple: breed type determines the baseline risk profile, and everything else — timing, monitoring, conditioning, route choice — is how you manage it. Start with an honest read of where your dog falls in the risk spectrum, then apply the standard heat management practices from there.
A Vizsla and a Bulldog are not having the same day at 82°F. Plan accordingly.
Breed-specific heatstroke risk data from Hall et al. 2020, Scientific Reports — Incidence and risk factors for heat-related illness in dogs in the UK. Brachycephalic breed airway physiology and panting efficiency consistent with published research on brachycephalic obstructive airway syndrome. Double-coated breed shaving risks and post-clipping alopecia discussed in AKC breed coat care guidance. Heatstroke cascade described in AVMA warm weather pet safety guidelines. Temperature thresholds are practical field guidelines based on published breed physiology research, not clinical diagnostic standards. Consult your veterinarian for guidance specific to your dog’s individual health status, conditioning level, and breed-specific considerations.
