Pollen Count & Forecast for San Antonio

San Antonio’s winter season (December-February) is dominated by Mountain Cedar pollen; Mountain Cedar (Juniperus ashei) prolific across the Texas Hill Country and northern suburbs. Spring (March-May) is dominated by Oak and Pecan pollen; Oak (Quercus) widespread in Brackenridge Park; Pecan (Carya illinoinensis) widespread along the San Antonio River. Late summer (August-October) sees high Ragweed (Ambrosia) and Grass (Poaceae) levels, originating from Phil Hardberger Park.

The Balcones Escarpment traps pollen during temperature inversions; south winds carry additional allergens from the Gulf Coast. Humid periods trigger high Mould (Alternaria, Cladosporium) spore counts; these are frequent along the Mission Reach and damp riverbanks.