Pollen is your enemy in the spring and fall if you have seasonal allergies. Pollen is the yellow powder that plants produce to fertilize other plants. In the meantime, it can cover cars and anything left outside and makes lots of people sneeze. Grass, tree and ragweed pollen flood the air during the cool nights and warm days of spring and fall. In most of the United States, pollen counts are usually highest from February until early summer. In the fall, plants typically release pollen from August to November. The worst month is usually September. Pollen counts are measurements of specific pollens in your area. Researchers have measured pollen counts for nearly 100 years. Over time, the counts have become more accurate and accessible. That's good news for allergy sufferers who need these reports to manage symptoms. Your local weather report probably includes pollen counts for your area. Weather apps on your cell phone often provide pollen counts and allergy forecasts, too. One example is the app for the Weather Channel. If you have seasonal allergies, you'll want to limit your exposure to pollen. Keeping tabs on the pollen count lets you know when it's safe to enjoy the outdoors—and when you should stay inside. Understanding Pollen Counts Across the country, pollen counting stations record pollen levels every day. Certified, trained counters use machines that measure pollen in the air. The machines usually are on a roof. They also measure the amount of mold in the air. Mold is another common seasonal allergen. The machines use rods or special traps that capture pollen. The amount of pollen in a machine indicates how much pollen is in the air at that time. A pollen count tells how many grains of pollen are in a cubic meter of air. When pollen counts are high, you're more likely to have allergy symptoms if you go outside. The counters also determine which types of pollen are highest. Sometimes they send the pollen to a lab to help figure this out. A pollen count and a pollen forecast are not the same thing. A forecast is an estimate of how much pollen will be in the air in your area. Forecasters use the weather and pollen counts from past years to predict pollen levels. However, a pollen count is an actual measurement of what's in the air that day. The pollen count might not match the pollen forecast. Some pollen counting stations report pollen counts differently. Usually, pollen counters report levels as absent, low, moderate, high or very high. Most stations report pollen counts in a similar way, such as low, low-medium, medium-high and high. What to Do for High Pollen Counts The best thing is to stay indoors if you have severe seasonal allergies and pollen counts are very high. If you have to be outside, take these steps to manage your allergies: Wear an allergy mask if you must be outside. Keep the windows closed in your home and car. Run the air conditioning in your home and car. Change your clothes and take a shower as soon as you come in from the outdoors. Make sure to shampoo your hair to wash off pollen. Wipe off pets that come in from the outdoors. They can carry in pollen on their fur. Wear sunglasses and a hat to keep pollen out of your eyes and hair. Just like you check the weather to plan your day, check your local pollen count every day. That way, you can plan the steps you need to take to better manage seasonal allergies.