It happens more than you'd think. A dog comes in for a routine full groom, and when we part the coat behind an ear or lift the fur along the neck, we find it: a red, wet-looking patch with hair matted flat against it, sometimes the size of a quarter, sometimes already spreading larger. The owner has no idea it's there — from the outside, the coat just looks a little damp. We stop what we're doing and let them know before we go any further. That's a hot spot, and it needs their vet's attention.
Hot spots are one of the most common skin conditions we flag at American Puppy during Missouri summers. They're not a grooming condition — they require a veterinarian to treat. But they are almost always grooming-preventable, and they peak right now: hot, humid, late June through August in the St. Charles and greater St. Louis area.
What Is a Hot Spot?
The medical name is acute moist dermatitis. Groomers and dog owners call them hot spots, and the name fits: they're hot to the touch, they appear quickly, and they tend to show up in warm, hidden spots on the body — behind an ear, along the neck or back, at the base of the tail, under the chest.
A hot spot looks like a red, moist, sometimes oozing patch of skin. The hair in and around it is often matted flat or missing entirely, because the dog has been scratching and licking at it. The skin looks raw and inflamed. They can start small — the size of a dime — or, left unnoticed for a day or two, spread quickly to the size of a palm.
The hallmark of a hot spot is how fast it appears. A dog can look completely normal in the morning and have a visible hot spot by evening. That rapid onset is one of the reasons they catch owners off guard — and why finding them at the grooming table is such a regular part of our summers.
Why Missouri Summers Are Prime Hot Spot Season
Hot spots need two things to develop: a trigger that irritates the skin, and trapped moisture. Missouri summers deliver both, all day, every day.
Our summer humidity in the St. Charles area — running high through July and August — means a dog's coat doesn't dry the way it does in drier climates. When a dog swims in a local lake or backyard pool, plays through a sprinkler, or just runs around on a humid afternoon and works up a good sweat, that moisture gets trapped in the coat. If the coat is thick, long, or unshorn, it can stay damp for hours. That warm, wet environment right against the skin is exactly where hot spots take hold.
Summer outdoor activity brings more triggers too: insect bites, contact with irritating grasses, and more opportunities for a dog to pick up a minor skin irritation that they then scratch and lick obsessively. That scratch-lick cycle is how a tiny bug bite becomes a significant hot spot in under 24 hours.
Floppy-eared breeds — Golden Retrievers, Labs, Cocker Spaniels, Basset Hounds — are especially prone to hot spots behind and under the ears in summer. Moisture from swimming or even heavy humidity collects in those ears, and between the ear flap and the neck, the skin can stay damp long after the rest of the dog has dried off.
The Grooming Connection: Why We See Fewer Hot Spots on Well-Kept Coats
Here's what we see consistently at the salon: the dogs most likely to come in with a hot spot during summer are the ones whose coat has grown long between appointments, who haven't had a deshed to clear out the dead undercoat, or who are carrying a mat they've been sitting against without anyone realizing it. The mat traps moisture. The moisture sits. The skin underneath gets irritated. The dog scratches. Hot spot.
Compare that to a dog who comes in on a regular schedule, stays trimmed for summer, and gets a thorough deshed to remove dead coat. That dog's fur dries faster after a swim. Air circulates closer to the skin. Moisture doesn't have anywhere to hide for hours on end. We're not saying a proper grooming routine makes a dog hot spot-proof — allergies, insect bites, and other triggers are outside anyone's control. But the pattern we see season after season is consistent: well-maintained coats and summer hot spots don't often turn up in the same dog.
If you've read our post on doodle matting in Missouri summer, some of this sounds familiar — trapped moisture, humidity, and an unshorn coat are the common thread. The hot spot is just a different outcome than a mat, and a more urgent one to address.
Where hot spots tend to show up most
In our experience at the salon, the locations that come up most often are:
- Behind and under the ears — especially on Labs, Goldens, and Cockers
- The neck and collar zone — moisture collects under collars and wet harnesses that don't dry quickly
- Along the back near the base of the tail — high-moisture area, particularly on heavy-coated breeds
- Under the chest and belly — contact with wet grass and damp ground
- Hip and thigh area — common on dogs who rest on damp surfaces outside
These are also the spots we check carefully during every full groom. Catching a hot spot early — before the dog has really worked at it — makes a meaningful difference in how quickly it heals once the dog sees the vet.
What We Do When We Find One at the Salon
When we spot something that looks like a hot spot during a groom, we pause and let you know immediately. Depending on the size, whether the skin is open, and whether the dog seems uncomfortable, we may ask that you check with your vet before we continue — especially if the hot spot is in a spot where bathing and blow-drying would put direct contact on irritated skin. In those cases, it's better to address the skin first.
We don't treat hot spots at the salon. That's veterinary work. What we can do is recognize them, describe what we found, and make sure you leave knowing what you're looking at. We've had owners tell us that catching it at the grooming table was what got their dog to the vet in time to treat it before it spread significantly.
If your dog currently has a hot spot and you're wondering whether to keep the grooming appointment, call us first. In many cases we can work around it. In others, it makes more sense to let the skin heal first. We'd rather have that conversation ahead of time than put a dog on the table while a hot spot is painful.
How to Lower the Risk This Summer
You can't prevent every hot spot — some triggers are simply out of anyone's control. But you can remove the conditions that let them take hold, and most of that comes down to keeping the coat dry and well-maintained through the summer months.
- Dry thoroughly after every swim or bath. A coat can look dry on the surface and still be damp underneath. In Missouri summer humidity, that moisture doesn't evaporate the way it does in a dry climate. At home, use a blow dryer on a low-heat setting rather than letting the dog air dry — and don't skip behind the ears and under the chest, which take longest to dry and are exactly where early hot spots develop.
- Keep up with grooming appointments through summer. This is not the time to let the coat grow long between visits. A trimmed coat dries faster, traps less moisture, and lets air reach the skin. For heavy-coated dogs, a deshed at the start of summer removes dead undercoat that would otherwise become a moisture trap all season long. Our summer grooming guide covers the right approach by coat type.
- Check the high-risk spots after outdoor time. A quick look behind the ears, along the collar line, and at the base of the tail after swimming or a long outdoor session takes about thirty seconds — and can catch a hot spot before the dog has had a chance to make it worse.
- Stay consistent with flea prevention. A flea bite on a sensitive dog sets off a scratch-lick cycle that leads directly to a hot spot. Your vet can recommend the right preventive — this is worth discussing at your next visit if you're not already on a summer routine.
- Act quickly if the dog fixates on a spot. A dog who won't leave one area of their body alone — licking, scratching, biting — is telling you something. Check the skin. If it looks red and wet, call your vet that day rather than waiting to see if it improves on its own.
When to See the Vet (Always, for an Actual Hot Spot)
If you find what looks like a hot spot — moist, red, raw skin with matted or missing hair, and a dog who's been obsessively licking or scratching that spot — call your vet that day. Hot spots spread quickly, and the dog's constant self-trauma keeps them from healing on their own. Home remedies are not the answer here; see your vet promptly.
Your vet will typically shave the area around the hot spot to allow air to reach the skin, clean it, and prescribe medication to address both the infection and the itch. Most hot spots resolve well with prompt treatment. The ones that are difficult to manage are the ones that sat for several days while the dog kept working at them.
The best prevention we know is a well-maintained coat all summer long — and that's exactly what we're here for. If you'd like to set up a summer grooming schedule or come in for a deshed before the hottest stretch of the season, you can book online here. We're at American Puppy in St. Charles, and summer skin conditions like hot spots are something we watch for with every dog that comes through our door.