The seasonal allergy cycle can begin and end at different times around the country. For example, in warm, southern climates, seasonal allergies can occur as early as January and end as late as November. Seasonal allergies traditionally fall into three categories:

Spring — Spring allergies may occur from January to May and are most often caused by tree pollen such as elm, maple, birch, poplar, beech, ash, oak, walnut, sycamore, cypress, hickory, pecan, cottonwood, and alder. A wet Spring can contribute to a higher mold count and higher pollen counts during the Summer months.

Late Spring/Summer — Summer allergies may occur from May to mid-July and are most often caused by grass pollen, such as: Bermuda, Timothy, Orchard, Sweet Vernal, June, and Johnson. A hot, wet Summer can contribute to high grass and weed pollen counts.

Fall — Fall allergies may occur from August to November and are most often caused by weed pollen such as Ragweed, Tumbleweed, Pigweed, Fireweed, and Lamb’s Quarters, tree pollen, and mold.

For more information on allergies, see the following links:

The American Academy of Allergy, Asthma and Immunology
Web MD Allergy Site

To monitor the daily local and nation allergy forecast, check out:
Pollen.com