Pollen Counts and Forecasts

Sneezing, sniffling, it’s so common these days with spring in full swing. Some people like to keep abreast of the pollen count to know what to expect, others take it for what it is and know it’s out of their hands and just go with it, popping their allergy meds as needed.

A pollen count is like a weather report, but instead of the weather, it indicates the concentration levels of all kinds of pollen (weed, grass, and tree pollen) in the air in a particular time in a certain region. It is measured in grains of pollen per square meter of air collected over 24 hours. The higher the count is, the more pollen is in the air and the more allergies will be effected.

For those interested, here are some sites where you can not only get pollen information, but the pollen counts and forecasts for your area:

www.pollen.com – Pollen.com provides allergy information and weather forecasts you can use every day. You can sign up to receive pollen alerts when the pollen count reaches the moderate level in your area. You can find information about terminology in the pollen library and check out the last 30 days in a given area on the pollen history page. You’ve also got a FAQ page with answers to questions regarding pollen count methodology and what is included in a pollen count. The home page also lists the worst and best cities of the day.

www.weather.com – You can check the pollen count and forecast for cities and zip codes and also learn about allergy tips and advice, pollen hot spots and natural allergy relief. The pollen count by city gives you the most active pollen types, for instance, it lists the reported tree, grass or weeds in particular that are highest at a given time, and a four day pollen forecast (ugh we’ve got a “very high” count coming up).

www.webmd.com – Provides a national map with overall pollen counts and you can find your zip code and get a reading with overall, grass, weed, tree and mold counts. Also provides information regarding allergy overview, tips and treatment.

More online pollen trackers: www.aaaai.org, www.weatherbug.com, cnn.com.

Some of the medical sites like Zyrtec provide information on pollen, but on some of them, you need to register. You can look at your local weather or news station to get this information as well, particular for your area. You can even find apps for phone to keep you abreast of pollen counts.

For those who suffer from pollen allergies, an online check of pollen counts is probably part of the daily routine, especially during the high pollen season of spring. However, at the recent Annual Meeting of the American Academy of Allergy, Asthma & Immunology (AAAAI) in San Francisco, researchers said that pollen counts are not always accurate. So now what are allergy sufferers to do with the pollen counts that they so depended on before?

After studying a number of websites compared to the findings of 13 of the AAAAI’s NAB Stations (National Allergy Bureau), they saw that the numbers did usually not correspond. Because these researchers know the inner workings of the NAB stations and the credibility of it, they saw that the other sites may not have verified or current information. For instance, one of the researchers reported that the predicted counts may be based on data from other years and more general forecasts. A lot needs to go in a pollen count to make it reputable.

Pollen has a number of factors regarding how it hits us, including the previous winter weather patterns, climate changes and current weather which all differ year to year. It also seems that the pollen seasons are lasting longer each year. In fact, according to an article in Medical News Today, the 2011 allergy season may be up to 27 days longer than the typical spring allergy season in North America. That is almost a month longer of suffering from pollen allergy symptoms.

Pollens are monitored using a “Rotorod” pollen sampler or any other plastic rod or similar device that is covered with silicone grease. Samples of particles in the air are collected on the rod as the device spins in the air at a controlled speed, usually for a 24-hour period. Afterwards, a trained analyst studies the surface of the rod under a microscope.  Pollens that were collected on the surface are identified and counted. A formula is then used to calculate that day’s pollen count. The media, physicians in the area, and the general public are then informed about the day’s readings.

Values above 76% are considered very high and almost all individuals with sensitivity to these airborne allergens will experience symptoms, and extremely sensitive people may have severe symptoms. Values from 51-75% are still high indicating that most affected individuals will experience symptoms. Values from 26-50% are moderate and indicate that symptoms will be experienced by many, but not all who have airborne allergies. Values from 1-25% are low and only those with extreme sensitivity will experience symptoms. A value of 0 means there is no trace of pollen in the air and symptoms are unlikely to manifest.

Pollen counts are always reported for a past time period and never for what is currently in the air. Depending on the skills of the analysts, some counts may not be as accurate and will reflect the day’s pollen concentration poorly. Some areas may just give a total pollen count that does not give a breakdown of the particular pollens that have the higher or lower count.

Rain is a big factor regarding pollen, and though a wet season brings forth beautiful plants, flowers and trees, and can actually hold off the pollen, when the pollen does strike, it’s usually worse due to more flowers. Though the rain can delay it, the heavy amounts this year have made the pollen counts climb high in many areas of the country.

Rain can also wash the pollen away and the wet, heavy pollen doesn’t assault people like the light, dry pollen can. However, once again, it’s a double edged sword because once the rains stops, the pollen can still be around. The rain only provides short reprieves and can even wash pollen from other areas to sufferers, giving them something new to sneeze about.

In general, on hot, dry and windy days, usually early in the morning, the quantity of pollen dispersed is greater than usual, and they stay in the air suspended for a longer period. Allergy symptoms are higher at these times. On chilly, wet, rainy, or windless days, pollen concentration is lower, and thus less allergy symptoms occur.

Pollen seems to be nobody’s friend and it is a tricky enemy. If you are someone who does look at pollen counts every day, make sure your information is coming from a reliable source, like the AAAAI or local weather stations. Treat accordingly and though we all like those rainy days that wash the pollen away, remember, at least for a few more weeks, it will be back.

Again, sometimes people just take their medicine regardless of the count and go about their business. Others need to stay attuned and modify their routines if the pollen gets to a certain level. Do what works best for you, stay healthy!


  1. Forget Pollen.com. It has become a hostile website. Only 30 day pollen counts for lousy Austin, TX are shown!

Leave a Reply to Darlene Russell Cancel reply

Your email address will not be published. Required fields are marked *