The pollen count in Miami peaks in February–May, though allergy sufferers can experience symptoms from as early as late winter. The Southeast has one of the longest allergy seasons in the country, often running February through October due to its warm, humid climate.
The primary driver is Grass — grass pollen affects more Americans than any other allergen — over 40 million people are sensitive to it. On warm, dry, and windy days the pollen count in Miami can spike dramatically, while rain temporarily brings it down.
Tree pollen starts in late winter and runs through spring. Grass pollen peaks during spring. Weed pollen is less of a concern in the southeast region.