If you’re looking out the window wishing for the rain to disappear, you may want to take a moment to rethink dashing out the door as soon as it stops.
Overall, rain is widely believed to provide brief respite from allergy symptoms, as the moisture weighs down the airborne pollen and literally washes pollen away and out of the air. Plants are also less likely to release large amounts of pollen during rainstorms, as warmer, drier air is more suitable for distribution. The Weather Channel states that rainy or windless days reduce pollen’s airborne circulation, lessening the impact of allergy symptoms overall.
But, that relief may only be temporary.
While rain may wash pollen out of the environment, it can also cause the pollen particles to burst and spread, according to experts at the American College of Allergy, Asthma and Immunology. After those even smaller particles are saturated with excess moisture, they are released into the air at a higher concentration. Once the rain stops, these fractured allergens can increase in severity because they are now smaller and inhaled more easily. This is why some people may suffer even worse allergy symptoms during or after a heavy rainfall.
Weather throughout the year plays a significant role in determining the duration and severity of an allergy season. For instance, large amounts of rainfall in the late fall, late winter or early spring can help plants, trees, and grass to grow, increasing pollination and pollen levels. Mild winters may also be indications of an early spring and subsequent intense allergy season. Certain regions or states see higher pollen counts due to low snow levels in winter and warmer temperatures in spring. Conversely, largely wet springs can have various effects depending on the time and density of that rainfall.
Experts say, if you are allergic to pollen, the longer the rain lasts, the better—the air should be fairly pollen-free during that time. But be warned, the post-rain air, filled with newly airborne pollen, may be difficult to handle. Ideally, rain showers lasting several days are better than alternating wet and dry days, according to an Internal Medicine and Allergy & Immunology expert.
Ultimately, pollen counts vary by time of day, season and weather conditions. Seasonal weather elements such as wind, temperature, moisture levels, and rain all play integral roles in determining the severity of an allergy season. While rain may seem like solution to your spring sneezing and sniffles, it may just be making matters worse.
Hauser, Annie. “Allergies Worse In or After Rain, Allergists Say”. Sept. 17, 2013
How Weather Affects Allergy Forecst. Retrieved April 30, 2016
Legg, Heather. Beyond Allergy. Retrieved April 30, 2016