One week your dog or cat is perfectly comfortable.

Then the season changes—and suddenly the paw licking, scratching, irritated ears, and red skin return.

It can seem like your pet is allergic to the weather. But there’s a better explanation:

Weather changes what your pet is exposed to.

Pollen, mould, humidity, and other environmental conditions fluctuate throughout the year. For pets with allergic skin disease, those changes can help trigger a seasonal flare.

Why Do Weather Changes Trigger Allergies in Dogs and Cats?

Seasonal changes can alter the amount and type of pollen, mould spores, humidity, moisture, and other environmental triggers your pet encounters.

In dogs, atopic dermatitis is now understood as a complex inflammatory skin disease involving allergic sensitization, immune dysregulation, the skin barrier, and the skin microbiome. https://pmc.ncbi.nlm.nih.gov/articles/PMC10874193/ 

Cats can also develop inflammatory, itchy skin disease associated with environmental allergens, known as feline atopic skin syndrome. https://pmc.ncbi.nlm.nih.gov/articles/PMC8543694/

So what changes when the weather does?

1. Different Seasons Bring Different Allergens

The outdoor environment isn't the same in April, July, and September.

Different plants release pollen at different times of year, while environmental conditions can influence other allergens.

That means a sensitive pet's exposure can change throughout the year—even when their food, home, and routine haven't.

Seasonality has also been documented in feline allergic skin disease, with environmental allergens capable of exacerbating symptoms. https://pmc.ncbi.nlm.nih.gov/articles/PMC5819051/

Same pet. Different season. Different exposure.

If the itching appears around the same time every year, that pattern is worth tracking.

2. Humidity Changes the Skin Environment

Pollen gets most of the attention during allergy season, but it isn't the whole story.

Humidity and moisture affect the environment surrounding the skin. That's important because allergic skin disease involves more than an immune reaction alone.

Research into canine atopic dermatitis shows that skin-barrier function and interactions between the skin and its microorganisms are important parts of the disease. https://pubmed.ncbi.nlm.nih.gov/25683702/

In other words, what's happening on the skin matters just as much as what's floating through the air.

3. The Skin Barrier Can Turn Itching Into a Cycle

Your pet's skin is a protective barrier between their body and the outside world.

In canine atopic dermatitis, abnormalities in that barrier are part of the disease process.

Then comes the problem every itchy-pet parent recognizes:

Itch → lick → scratch → irritated skin → more itch

Repeated scratching and licking can further challenge already-irritated skin, allowing a small seasonal flare to become much harder to settle.

4. Why Are the Paws and Ears Often Involved?

Think about where your dog's paws have been today.

Grass. Leaves. Soil. Trails. Sidewalks. The backyard.

Paws are constantly interacting with the environment—and then many itchy dogs come inside and immediately start licking them.

The ears, face, belly, and skin folds can also become problem areas in dogs with allergic skin disease.

So when seasonal itching appears, paying attention to where your pet is irritated can be just as useful as noticing when it happens.

5. The Skin Microbiome Adds Another Layer

Your pet's skin has its own ecosystem of bacteria, fungi, and other microorganisms.

Studies show that dogs with atopic dermatitis tend to have lower microbial diversity than healthy dogs, with increased relative abundance of organisms including Staphylococcus pseudintermedius and Malassezia pachydermatis.

Scientists are still determining whether these microbial changes are a cause, consequence, or combination of both.

But they help explain why an allergy flare may involve more than scratching.

You may also notice:

paw licking • redness • irritated ears • odour • greasy skin • hot spots

6. Cats Can Have Seasonal Skin Allergies Too

Cats don't always advertise itching the way dogs do.

You might instead notice excessive grooming, self-induced hair loss, scratching around the head or neck, or irritated skin.

Feline atopic skin syndrome is recognized as an inflammatory and itchy condition that can be associated with environmental allergens. However, allergic skin disease is less well understood in cats than in dogs, so we shouldn't simply assume everything discovered in dogs applies equally to cats.

If your cat's excessive grooming seems to return at the same time each year, the seasonal pattern may be an important clue.

What Can You Do During Seasonal Changes?

Start by tracking the pattern.

When did the itching begin? Is it worse after time outside? Does the same thing happen every spring or fall? Are the paws, ears, or belly consistently affected?

After outdoor activity, gently cleaning exposed areas such as the paws can also help remove dirt and foreign material picked up outside.

For pets prone to seasonal itching, we also like to think about support in three areas:

Gut & immune health → irritated skin → skin recovery

That's the idea behind the Myco Pet Itchy Pet Protocol.

A 3-Step Approach to Itchy Pets

The Myco Pet Itchy Pet Protocol combines three products with different roles:

Step 1 — Gut & Immunity+ supports gut health, microbiome balance, and normal immune function.

Step 2 — PROTECT provides topical support for itchy and irritated areas including the paws, outer ears, skin folds, and hot spots.

Step 3 — Lean Mass+ provides nutritional support for tissue health, recovery, and a healthy skin barrier.

Rather than looking only at the itch itself, the protocol takes a broader inside + outside + recovery approach.

The Bottom Line

Your pet probably isn't allergic to the weather.

They're responding to an environment that changes with the weather.

Different seasons bring different allergens and conditions—and in susceptible pets, the immune system, skin barrier, and skin microbiome can all be part of the response.

So when the scratching suddenly returns, look at the calendar.

That seasonal pattern might be telling you more than you think.