Pollen Season 2026: Complete Guide To Timing, Counts And Allergy Relief

These Plants Cause The Most Allergies

Did you know that a single ragweed plant can produce 1 billion grains of pollen in a season? Or that most pollen that causes allergy problems is so small that it is invisible to the human eye?

From an evolutionary perspective, pollen represents a triumphant and ingenious reproductive strategy. These microscopic cells can carry genetic material across vast distances as they hitch rides on air currents, allowing plants that are rooted in place to seed a next generation far away. This amazing dispersal ability, while crucial for plant reproduction, is also what makes pollen such a persistent challenge for allergy sufferers. Love it or hate it, this time of the season, we all have to deal with it.

Here's our helpful guide to understanding pollen and why it can have such large impacts on our health.

Understanding Pollen

Pollen is a fine powder made by some plants in order to reproduce. When pollen is released, it’s light enough that it can be carried by the wind to other plants. Unfortunately for any human with seasonal allergies, plants and trees make a lot of pollen. And a good deal of that pollen ends up lingering in the air, where humans breathe it in.

Allergic reactions to pollen occur when our immune systems mistakenly believe that certain types of pollen we encounter are harmful. The symptoms that many of us experience from seasonal allergies, which can include congestion, sneezing and itchy eyes, happen because our immune systems overreact to this perceived threat.

When Is Pollen Season?

Pollen season timing varies dramatically across the country. Southern states like Georgia, Texas, and the Carolinas often start as early as January with oak, pine, and cedar pollen, frequently recording some of the nation's highest pollen counts during peak spring months. The Northeast and Midwest typically begin later in March or April but face intense ragweed seasons in late summer and fall. The Pacific Northwest faces unique challenges with alder and birch pollen in early spring, while desert Southwest residents contend with desert broom and palo verde trees.

Research indicates that climate change is making pollen season longer and more intense, with data showing that pollen concentrations in North America increased 21% between 1990 and 2018 and that the pollen season increased by 20 days over the same time period.

What Is The Pollen Count?

The pollen count combines all pollen types into one daily number, expressing it in pollen grains per cubic meter of air, so that you can quickly see the pollen density in the air. If you know what types of pollen aggravate your symptoms, you can find a three-day outlook of tree pollen, grass pollen and ragweed pollen in the pollen breakdown.

Everyone’s seasonal allergies are different, so a particular pollen count might make one person sneeze all day and another person feel perfectly fine. An effective way of using the pollen count, therefore, is to keep track of them every day. That way, you can understand what a particular pollen count or breakdown will mean for your allergies. It may also be helpful to see an allergist for allergy testing.

Asthma And Pollen

Some people suffer from allergic asthma, in which breathing in certain allergens can cause their airways to tighten. If you experience symptoms like feeling short of breath, coughing, wheezing or chest tightness as the result of seasonal allergies, consult your doctor to come up with a treatment plan in case of an asthma attack.

How Can You Prepare?

What to Do During High Pollen Days

When pollen counts soar, strategic planning can make the difference between misery and manageable symptoms. Start by timing outdoor activities carefully. Since pollen release peaks between 5-10 AM, plan outdoor exercise or yard work for late afternoon or early evening when counts typically drop.

Before heading outside, check your local pollen forecast and consider wearing wraparound sunglasses to protect your eyes. If you must be outdoors during high pollen times, a surgical face mask can reduce pollen exposure significantly. After outdoor activities, change clothes immediately and shower before bed to avoid transferring pollen to your bedding.

For your home, keep windows closed and run air conditioning on recirculate mode. If you don't have AC, strategically open windows late at night, when pollen counts are lowest. Avoid hanging laundry outside to dry on high pollen days, and consider running air purifiers in bedrooms and main living areas.

When driving, use recirculated air instead of fresh air intake. This simple switch can significantly reduce in-car pollen exposure. Park in garages when possible, and keep car windows closed even during short trips.

Does Rain Reduce Pollen?

Rain has a complex relationship with pollen: While it might initially help allergy sufferers, it can ultimately make symptoms worse. Here's why. When rain first begins, pollen counts typically drop. This happens because water vapor and raindrops are heavier than pollen particles, and pull already-airborne pollen out of the air. The accompanying humidity also weighs down remaining pollen, making it less likely to become airborne and cause symptoms.

However, rain's pollen-reducing benefits are short-lived. After rainfall, plants tend to grow more vigorously due to nitrates in rainwater, leading to increased flowering and pollen production. Heavy rainstorms can also break up larger pollen clumps into smaller, more easily airborne particles. When the rain stops, especially if followed by windy conditions, these smaller pollen fragments can create even higher pollen counts than before the storm.

Finally, rain and humidity can trigger mold growth, creating problems for those with mold allergies. The moisture encourages mold spores to multiply, particularly in damp areas of homes. In other words, while a light rain might provide temporary pollen relief, don't be surprised if your allergy symptoms actually worsen in the days following heavy rainfall.

When To Seek Medical Help

Beyond regular allergist testing, you should consult a doctor if your symptoms last longer than typical seasons or interfere significantly with sleep and daily activities. Red flags that warrant medical attention include persistent symptoms that don't respond to over-the-counter medications or symptoms that seem to worsen despite treatment efforts.

Senior writer Chris DeWeese edits Morning Brief, The Weather Channel’s newsletter.