Summer Allergies: What are they?

The sun is shining, children are out of school, and summer vacation plans are in full effect. What happens when suddenly you wake up with a sore throat, stuffy nose, and chest congestion? Is it summer allergies, or is it a cold? Though most people associate seasonal allergies with springtime, the summer brings an entirely new set of allergens that have an equal disregard for the havoc that they can wreak on your plans with your family and friends.

What causes allergies during the summer?

Though spring pollen allergies can last through the early days of summer, for many regions, the hotter months of June, July, and August bring with them an entirely new set of pollen from certain types of grass and weeds. As a general rule:

Trees, such as oak, birch, and mountain cedar pollinate in the spring. Other sources of tree pollen include pine, mulberry, and palm trees. A mild winter can cause trees and other plants to start pollinating early.

Grass and some weeds, such as mugwort, nettle, and bermudagrass pollinate in the summer. Other sources of summer pollen allergies include Timothy, Kentucky, orchard, rye, and sweet vernal grasses. In regions with a tropical climate, grass can pollinate for most of the year.

Weeds, such as ragweed, tend to pollinate in the fall and usually keep growing until the first frost.

Late summer allergies

Some may experience allergies towards the end of summer, and ragweed and other weeds may be to blame. Though ragweed’s peak season is around early September, most ragweed begins to bloom in the late summer, usually in mid-August. Other sources of pollen in the late summer and fall include burning bush, cocklebur, sagebrush, and tumbleweed.


Mold is another common summer allergen. A fungus that thrives in hot, humid environments, mold spreads through microscopic spores that travel on the wind. When inhaled, these spores can cause allergy symptoms in those with a mold allergy. Outdoor mold growth is usually highest in the late summer and early fall, though some climates can experience mold growth year-round. A rainy spring can lead to an increase in mold growth throughout the summer and fall months. Outdoor mold sources include piles of leaves or compost, rotting logs, grasses, and grains.

Impact of weather conditions

Throughout the seasons, pollen counts will vary with the weather conditions. For example, pollen counts are highest on warm, windy days, especially those following rainfall. The exact pollination timeline will depend on the climate and growing seasons in your geographic location.

Staying up-to-date with the pollen and mold spore counts in your city can help you plan outdoor activities and avoid the worst of your allergy symptoms.

What are summer allergy symptoms?

Many people are faced with respiratory symptoms during the summer, but, once spring has passed, they may be less likely to attribute these symptoms to seasonal allergies. However, as discussed above, allergy triggers can be just as plentiful in the summer and early fall as they are in the spring. According to the Asthma and Allergy Foundation of America and the U.S. National Library of Medicine, summer allergy symptoms may include:

Increased mucus production

Runny or stuffy nose

Sneezing, coughing, and wheezing

Itching eyes nose or throat

Sore throat

Red, watery eyes

Swelling around the eyes or dark circles under the eyes

Hives or dry, scaling skin

Is it a summer cold or allergies?

Depending on your symptoms, it can be challenging to tell the difference between a summer cold and allergies. However, the distinction is important, especially when it comes to choosing treatment methods and determining whether you are contagious. If you are unsure, you may want to ask your physician. However, according to the National Institutes of Health, some general key differences between allergies and colds are:

A cold usually lasts three to five days, but allergy symptoms can last weeks or even months.

Symptoms may overlap, but a cold can come with general aches and pains, while allergies are typically accompanied by more itchy symptoms.

Seasonal allergy symptoms happen around the same time each year and are triggered by allergens such as pollen and mold spores, but cold symptoms generally occur after exposure to the cold virus.

Colds are contagious, but allergies are not.

Cold treatment usually involves getting plenty of rest and taking decongestants and over-the-counter painkillers to treat symptoms until the virus has run its course. Allergy treatment tends to be more focused on avoiding contact with allergy triggers and finding the right combination of medicine, such as antihistamines, steroid nasal sprays, and decongestants, to manage your symptoms.

Other summer air quality concerns

The increased heat and humidity in the summer can pose some serious air quality risks that can aggravate symptoms in those with allergies and asthma. For example, smog—caused by the chemical reaction of volatile organic compounds (VOCs), nitrogen oxides, and sunlight—is a major summer air quality concern. Though industrial and traffic air pollution can be an issue year-round, the longer sunlight hours can increase smog production in the summer, which, paired with low levels of summertime wind, can cause air pollution in some regions of the United States to build up to potentially dangerous levels.

Other summertime allergy triggers include chlorine and wood smoke. Though you cannot be allergic to chlorine, frequent exposure to this element (and other pool cleaning products) can irritate and sensitize your respiratory system, which may increase your chances of developing asthma and allergies, according to the American College of Allergy, Asthma and Immunology (ACAAI). Additionally, those sensitive to chlorine may develop hives or red, itchy skin patches after swimming.

Wood smoke, caused by either campfires, bonfires, or wildfires, contains high levels of solid and gaseous pollutants that can irritate the respiratory tract and cause allergy-like symptoms such as burning eyes and a runny nose, as well as more severe health effects including bronchitis, asthma attacks, and heart conditions. According to the EPA, wood smoke can contain benzene, formaldehyde, acrolein, and polycyclic aromatic hydrocarbons (PAHs).

Tips on dealing with summer allergies.

The last thing that you want to do is deal with allergies during the dog days of summer. So how can you keep yourself and your family safe from unpleasant allergy symptoms? The main preventative actions that you can take are to think critically, spot any potential opportunities for allergen exposure, and plan accordingly so that you can enjoy the long, sunny days of summer without constantly worrying about tissues and allergy medicine. To better prepare for and deal with summer allergies, you can:

Check air quality reports and schedule outdoor activities on days when mold spore and pollen counts are low.

Reduce allergen presence in your home by controlling relative humidity levels, dusting, and vacuuming regularly, and using your HVAC system to cool your house instead of opening doors and windows.

Avoid tracking pollen indoors by changing your clothing after spending time outdoors and leaving your shoes by the front door. Additionally, cleaning pets with a damp rag after they come in from outdoors can help keep them from spreading pollen throughout your home.

Springtime is over, but that does not mean the end of allergy season. Fortunately, you can protect yourself and your family from the health effects of summer air quality concerns such as pollen, mold spores, and smog. By taking care to avoid going outside on bad air quality days and decreasing allergen exposure whenever possible, you can keep yourself from being weighed down by allergy symptoms and focus on enjoying your summer.

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