Residents of Bellevue and surrounding areas may experience varying levels of pollen exposure throughout the year. Those with allergies to alder, birch, grass, mugwort, or nettle should be particularly cautious during their respective peak seasons. The Pacific Northwest's frequent rainfall provides some relief by reducing airborne pollen, but individuals with severe allergies should remain vigilant during dry periods. The highest risks occur in late spring and summer when grass pollen peaks, and in early fall with mugwort and nettle.